Context stringlengths 57 6.04k | file_name stringlengths 21 79 | start int64 14 1.49k | end int64 18 1.5k | theorem stringlengths 25 1.55k | proof stringlengths 5 7.36k | eval_complexity float64 0 1 |
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import Mathlib.Algebra.BigOperators.Finprod
import Mathlib.Algebra.Group.ConjFinite
import Mathlib.Algebra.Group.Subgroup.Finite
import Mathlib.Data.Set.Card
import Mathlib.GroupTheory.Subgroup.Center
open MulAction ConjClasses
variable (G : Type*) [Group G]
theorem sum_conjClasses_card_eq_card [Fintype <| ConjClasses G] [Fintype G]
[∀ x : ConjClasses G, Fintype x.carrier] :
∑ x : ConjClasses G, x.carrier.toFinset.card = Fintype.card G := by
suffices (Σ x : ConjClasses G, x.carrier) ≃ G by simpa using (Fintype.card_congr this)
simpa [carrier_eq_preimage_mk] using Equiv.sigmaFiberEquiv ConjClasses.mk
theorem Group.sum_card_conj_classes_eq_card [Finite G] :
∑ᶠ x : ConjClasses G, x.carrier.ncard = Nat.card G := by
classical
cases nonempty_fintype G
rw [Nat.card_eq_fintype_card, ← sum_conjClasses_card_eq_card, finsum_eq_sum_of_fintype]
simp [Set.ncard_eq_toFinset_card']
| Mathlib/GroupTheory/ClassEquation.lean | 47 | 70 | theorem Group.nat_card_center_add_sum_card_noncenter_eq_card [Finite G] :
Nat.card (Subgroup.center G) + ∑ᶠ x ∈ noncenter G, Nat.card x.carrier = Nat.card G := by |
classical
cases nonempty_fintype G
rw [@Nat.card_eq_fintype_card G, ← sum_conjClasses_card_eq_card, ←
Finset.sum_sdiff (ConjClasses.noncenter G).toFinset.subset_univ]
simp only [Nat.card_eq_fintype_card, Set.toFinset_card]
congr 1
swap
· convert finsum_cond_eq_sum_of_cond_iff _ _
simp [Set.mem_toFinset]
calc
Fintype.card (Subgroup.center G) = Fintype.card ((noncenter G)ᶜ : Set _) :=
Fintype.card_congr ((mk_bijOn G).equiv _)
_ = Finset.card (Finset.univ \ (noncenter G).toFinset) := by
rw [← Set.toFinset_card, Set.toFinset_compl, Finset.compl_eq_univ_sdiff]
_ = _ := ?_
rw [Finset.card_eq_sum_ones]
refine Finset.sum_congr rfl ?_
rintro ⟨g⟩ hg
simp only [noncenter, Set.not_subsingleton_iff, Set.toFinset_setOf, Finset.mem_univ, true_and,
forall_true_left, Finset.mem_sdiff, Finset.mem_filter, Set.not_nontrivial_iff] at hg
rw [eq_comm, ← Set.toFinset_card, Finset.card_eq_one]
exact ⟨g, Finset.coe_injective <| by simpa using hg.eq_singleton_of_mem mem_carrier_mk⟩
| 0 |
import Mathlib.RingTheory.WittVector.Basic
import Mathlib.RingTheory.WittVector.IsPoly
#align_import ring_theory.witt_vector.init_tail from "leanprover-community/mathlib"@"0798037604b2d91748f9b43925fb7570a5f3256c"
variable {p : ℕ} [hp : Fact p.Prime] (n : ℕ) {R : Type*} [CommRing R]
-- type as `\bbW`
local notation "𝕎" => WittVector p
namespace WittVector
open MvPolynomial
open scoped Classical
noncomputable section
section
def select (P : ℕ → Prop) (x : 𝕎 R) : 𝕎 R :=
mk p fun n => if P n then x.coeff n else 0
#align witt_vector.select WittVector.select
section Select
variable (P : ℕ → Prop)
def selectPoly (n : ℕ) : MvPolynomial ℕ ℤ :=
if P n then X n else 0
#align witt_vector.select_poly WittVector.selectPoly
theorem coeff_select (x : 𝕎 R) (n : ℕ) :
(select P x).coeff n = aeval x.coeff (selectPoly P n) := by
dsimp [select, selectPoly]
split_ifs with hi
· rw [aeval_X, mk]; simp only [hi]; rfl
· rw [AlgHom.map_zero, mk]; simp only [hi]; rfl
#align witt_vector.coeff_select WittVector.coeff_select
-- Porting note: replaced `@[is_poly]` with `instance`. Made the argument `P` implicit in doing so.
instance select_isPoly {P : ℕ → Prop} : IsPoly p fun _ _ x => select P x := by
use selectPoly P
rintro R _Rcr x
funext i
apply coeff_select
#align witt_vector.select_is_poly WittVector.select_isPoly
theorem select_add_select_not : ∀ x : 𝕎 R, select P x + select (fun i => ¬P i) x = x := by
-- Porting note: TC search was insufficient to find this instance, even though all required
-- instances exist. See zulip: [https://leanprover.zulipchat.com/#narrow/stream/287929-mathlib4/topic/WittVector.20saga/near/370073526]
have : IsPoly p fun {R} [CommRing R] x ↦ select P x + select (fun i ↦ ¬P i) x :=
IsPoly₂.diag (hf := IsPoly₂.comp)
ghost_calc x
intro n
simp only [RingHom.map_add]
suffices
(bind₁ (selectPoly P)) (wittPolynomial p ℤ n) +
(bind₁ (selectPoly fun i => ¬P i)) (wittPolynomial p ℤ n) =
wittPolynomial p ℤ n by
apply_fun aeval x.coeff at this
simpa only [AlgHom.map_add, aeval_bind₁, ← coeff_select]
simp only [wittPolynomial_eq_sum_C_mul_X_pow, selectPoly, AlgHom.map_sum, AlgHom.map_pow,
AlgHom.map_mul, bind₁_X_right, bind₁_C_right, ← Finset.sum_add_distrib, ← mul_add]
apply Finset.sum_congr rfl
refine fun m _ => mul_eq_mul_left_iff.mpr (Or.inl ?_)
rw [ite_pow, zero_pow (pow_ne_zero _ hp.out.ne_zero)]
by_cases Pm : P m
· rw [if_pos Pm, if_neg $ not_not_intro Pm, zero_pow Fin.size_pos'.ne', add_zero]
· rwa [if_neg Pm, if_pos, zero_add]
#align witt_vector.select_add_select_not WittVector.select_add_select_not
| Mathlib/RingTheory/WittVector/InitTail.lean | 112 | 133 | theorem coeff_add_of_disjoint (x y : 𝕎 R) (h : ∀ n, x.coeff n = 0 ∨ y.coeff n = 0) :
(x + y).coeff n = x.coeff n + y.coeff n := by |
let P : ℕ → Prop := fun n => y.coeff n = 0
haveI : DecidablePred P := Classical.decPred P
set z := mk p fun n => if P n then x.coeff n else y.coeff n
have hx : select P z = x := by
ext1 n; rw [select, coeff_mk, coeff_mk]
split_ifs with hn
· rfl
· rw [(h n).resolve_right hn]
have hy : select (fun i => ¬P i) z = y := by
ext1 n; rw [select, coeff_mk, coeff_mk]
split_ifs with hn
· exact hn.symm
· rfl
calc
(x + y).coeff n = z.coeff n := by rw [← hx, ← hy, select_add_select_not P z]
_ = x.coeff n + y.coeff n := by
simp only [z, mk.eq_1]
split_ifs with y0
· rw [y0, add_zero]
· rw [h n |>.resolve_right y0, zero_add]
| 0 |
import Mathlib.Tactic.Ring
import Mathlib.Data.PNat.Prime
#align_import data.pnat.xgcd from "leanprover-community/mathlib"@"6afc9b06856ad973f6a2619e3e8a0a8d537a58f2"
open Nat
namespace PNat
structure XgcdType where
wp : ℕ
x : ℕ
y : ℕ
zp : ℕ
ap : ℕ
bp : ℕ
deriving Inhabited
#align pnat.xgcd_type PNat.XgcdType
namespace XgcdType
variable (u : XgcdType)
instance : SizeOf XgcdType :=
⟨fun u => u.bp⟩
instance : Repr XgcdType where
reprPrec
| g, _ => s!"[[[{repr (g.wp + 1)}, {repr g.x}], \
[{repr g.y}, {repr (g.zp + 1)}]], \
[{repr (g.ap + 1)}, {repr (g.bp + 1)}]]"
def mk' (w : ℕ+) (x : ℕ) (y : ℕ) (z : ℕ+) (a : ℕ+) (b : ℕ+) : XgcdType :=
mk w.val.pred x y z.val.pred a.val.pred b.val.pred
#align pnat.xgcd_type.mk' PNat.XgcdType.mk'
def w : ℕ+ :=
succPNat u.wp
#align pnat.xgcd_type.w PNat.XgcdType.w
def z : ℕ+ :=
succPNat u.zp
#align pnat.xgcd_type.z PNat.XgcdType.z
def a : ℕ+ :=
succPNat u.ap
#align pnat.xgcd_type.a PNat.XgcdType.a
def b : ℕ+ :=
succPNat u.bp
#align pnat.xgcd_type.b PNat.XgcdType.b
def r : ℕ :=
(u.ap + 1) % (u.bp + 1)
#align pnat.xgcd_type.r PNat.XgcdType.r
def q : ℕ :=
(u.ap + 1) / (u.bp + 1)
#align pnat.xgcd_type.q PNat.XgcdType.q
def qp : ℕ :=
u.q - 1
#align pnat.xgcd_type.qp PNat.XgcdType.qp
def vp : ℕ × ℕ :=
⟨u.wp + u.x + u.ap + u.wp * u.ap + u.x * u.bp, u.y + u.zp + u.bp + u.y * u.ap + u.zp * u.bp⟩
#align pnat.xgcd_type.vp PNat.XgcdType.vp
def v : ℕ × ℕ :=
⟨u.w * u.a + u.x * u.b, u.y * u.a + u.z * u.b⟩
#align pnat.xgcd_type.v PNat.XgcdType.v
def succ₂ (t : ℕ × ℕ) : ℕ × ℕ :=
⟨t.1.succ, t.2.succ⟩
#align pnat.xgcd_type.succ₂ PNat.XgcdType.succ₂
theorem v_eq_succ_vp : u.v = succ₂ u.vp := by
ext <;> dsimp [v, vp, w, z, a, b, succ₂] <;> ring_nf
#align pnat.xgcd_type.v_eq_succ_vp PNat.XgcdType.v_eq_succ_vp
def IsSpecial : Prop :=
u.wp + u.zp + u.wp * u.zp = u.x * u.y
#align pnat.xgcd_type.is_special PNat.XgcdType.IsSpecial
def IsSpecial' : Prop :=
u.w * u.z = succPNat (u.x * u.y)
#align pnat.xgcd_type.is_special' PNat.XgcdType.IsSpecial'
| Mathlib/Data/PNat/Xgcd.lean | 150 | 156 | theorem isSpecial_iff : u.IsSpecial ↔ u.IsSpecial' := by |
dsimp [IsSpecial, IsSpecial']
let ⟨wp, x, y, zp, ap, bp⟩ := u
constructor <;> intro h <;> simp [w, z, succPNat] at * <;>
simp only [← coe_inj, mul_coe, mk_coe] at *
· simp_all [← h, Nat.mul, Nat.succ_eq_add_one]; ring
· simp [Nat.succ_eq_add_one, Nat.mul_add, Nat.add_mul, ← Nat.add_assoc] at h; rw [← h]; ring
| 0 |
import Mathlib.Algebra.MonoidAlgebra.Division
import Mathlib.Algebra.MvPolynomial.Basic
#align_import data.mv_polynomial.division from "leanprover-community/mathlib"@"72c366d0475675f1309d3027d3d7d47ee4423951"
variable {σ R : Type*} [CommSemiring R]
namespace MvPolynomial
theorem monomial_dvd_monomial {r s : R} {i j : σ →₀ ℕ} :
monomial i r ∣ monomial j s ↔ (s = 0 ∨ i ≤ j) ∧ r ∣ s := by
constructor
· rintro ⟨x, hx⟩
rw [MvPolynomial.ext_iff] at hx
have hj := hx j
have hi := hx i
classical
simp_rw [coeff_monomial, if_pos] at hj hi
simp_rw [coeff_monomial_mul'] at hi hj
split_ifs at hi hj with hi hi
· exact ⟨Or.inr hi, _, hj⟩
· exact ⟨Or.inl hj, hj.symm ▸ dvd_zero _⟩
-- Porting note: two goals remain at this point in Lean 4
· simp_all only [or_true, dvd_mul_right, and_self]
· simp_all only [ite_self, le_refl, ite_true, dvd_mul_right, or_false, and_self]
· rintro ⟨h | hij, d, rfl⟩
· simp_rw [h, monomial_zero, dvd_zero]
· refine ⟨monomial (j - i) d, ?_⟩
rw [monomial_mul, add_tsub_cancel_of_le hij]
#align mv_polynomial.monomial_dvd_monomial MvPolynomial.monomial_dvd_monomial
@[simp]
theorem monomial_one_dvd_monomial_one [Nontrivial R] {i j : σ →₀ ℕ} :
monomial i (1 : R) ∣ monomial j 1 ↔ i ≤ j := by
rw [monomial_dvd_monomial]
simp_rw [one_ne_zero, false_or_iff, dvd_rfl, and_true_iff]
#align mv_polynomial.monomial_one_dvd_monomial_one MvPolynomial.monomial_one_dvd_monomial_one
@[simp]
theorem X_dvd_X [Nontrivial R] {i j : σ} :
(X i : MvPolynomial σ R) ∣ (X j : MvPolynomial σ R) ↔ i = j := by
refine monomial_one_dvd_monomial_one.trans ?_
simp_rw [Finsupp.single_le_iff, Nat.one_le_iff_ne_zero, Finsupp.single_apply_ne_zero,
ne_eq, not_false_eq_true, and_true]
set_option linter.uppercaseLean3 false in
#align mv_polynomial.X_dvd_X MvPolynomial.X_dvd_X
@[simp]
| Mathlib/Algebra/MvPolynomial/Division.lean | 260 | 263 | theorem X_dvd_monomial {i : σ} {j : σ →₀ ℕ} {r : R} :
(X i : MvPolynomial σ R) ∣ monomial j r ↔ r = 0 ∨ j i ≠ 0 := by |
refine monomial_dvd_monomial.trans ?_
simp_rw [one_dvd, and_true_iff, Finsupp.single_le_iff, Nat.one_le_iff_ne_zero]
| 0 |
import Mathlib.Algebra.Order.Ring.Abs
import Mathlib.Combinatorics.SimpleGraph.Coloring
import Mathlib.Combinatorics.SimpleGraph.Hasse
import Mathlib.Order.OmegaCompletePartialOrder
namespace SimpleGraph
def pathGraph.bicoloring (n : ℕ) :
Coloring (pathGraph n) Bool :=
Coloring.mk (fun u ↦ u.val % 2 = 0) <| by
intro u v
rw [pathGraph_adj]
rintro (h | h) <;> simp [← h, not_iff, Nat.succ_mod_two_eq_zero_iff]
def pathGraph_two_embedding (n : ℕ) (h : 2 ≤ n) : pathGraph 2 ↪g pathGraph n where
toFun v := ⟨v, trans v.2 h⟩
inj' := by
rintro v w
rw [Fin.mk.injEq]
exact Fin.ext
map_rel_iff' := by
intro v w
fin_cases v <;> fin_cases w <;> simp [pathGraph, ← Fin.coe_covBy_iff]
| Mathlib/Combinatorics/SimpleGraph/ConcreteColorings.lean | 43 | 49 | theorem chromaticNumber_pathGraph (n : ℕ) (h : 2 ≤ n) :
(pathGraph n).chromaticNumber = 2 := by |
have hc := (pathGraph.bicoloring n).colorable
apply le_antisymm
· exact hc.chromaticNumber_le
· simpa only [pathGraph_two_eq_top, chromaticNumber_top] using
chromaticNumber_mono_of_embedding (pathGraph_two_embedding n h)
| 0 |
import Mathlib.Geometry.Manifold.ChartedSpace
#align_import geometry.manifold.local_invariant_properties from "leanprover-community/mathlib"@"431589bce478b2229eba14b14a283250428217db"
noncomputable section
open scoped Classical
open Manifold Topology
open Set Filter TopologicalSpace
variable {H M H' M' X : Type*}
variable [TopologicalSpace H] [TopologicalSpace M] [ChartedSpace H M]
variable [TopologicalSpace H'] [TopologicalSpace M'] [ChartedSpace H' M']
variable [TopologicalSpace X]
namespace StructureGroupoid
variable (G : StructureGroupoid H) (G' : StructureGroupoid H')
structure LocalInvariantProp (P : (H → H') → Set H → H → Prop) : Prop where
is_local : ∀ {s x u} {f : H → H'}, IsOpen u → x ∈ u → (P f s x ↔ P f (s ∩ u) x)
right_invariance' : ∀ {s x f} {e : PartialHomeomorph H H},
e ∈ G → x ∈ e.source → P f s x → P (f ∘ e.symm) (e.symm ⁻¹' s) (e x)
congr_of_forall : ∀ {s x} {f g : H → H'}, (∀ y ∈ s, f y = g y) → f x = g x → P f s x → P g s x
left_invariance' : ∀ {s x f} {e' : PartialHomeomorph H' H'},
e' ∈ G' → s ⊆ f ⁻¹' e'.source → f x ∈ e'.source → P f s x → P (e' ∘ f) s x
#align structure_groupoid.local_invariant_prop StructureGroupoid.LocalInvariantProp
variable {G G'} {P : (H → H') → Set H → H → Prop} {s t u : Set H} {x : H}
variable (hG : G.LocalInvariantProp G' P)
namespace LocalInvariantProp
| Mathlib/Geometry/Manifold/LocalInvariantProperties.lean | 82 | 85 | theorem congr_set {s t : Set H} {x : H} {f : H → H'} (hu : s =ᶠ[𝓝 x] t) : P f s x ↔ P f t x := by |
obtain ⟨o, host, ho, hxo⟩ := mem_nhds_iff.mp hu.mem_iff
simp_rw [subset_def, mem_setOf, ← and_congr_left_iff, ← mem_inter_iff, ← Set.ext_iff] at host
rw [hG.is_local ho hxo, host, ← hG.is_local ho hxo]
| 0 |
import Mathlib.RingTheory.HahnSeries.Addition
import Mathlib.Algebra.Algebra.Subalgebra.Basic
import Mathlib.Data.Finset.MulAntidiagonal
#align_import ring_theory.hahn_series from "leanprover-community/mathlib"@"a484a7d0eade4e1268f4fb402859b6686037f965"
set_option linter.uppercaseLean3 false
open Finset Function
open scoped Classical
open Pointwise
noncomputable section
variable {Γ Γ' R : Type*}
section Multiplication
@[nolint unusedArguments]
def HahnModule (Γ R V : Type*) [PartialOrder Γ] [Zero V] [SMul R V] :=
HahnSeries Γ V
namespace HahnModule
section
variable {Γ R V : Type*} [PartialOrder Γ] [Zero V] [SMul R V]
def of {Γ : Type*} (R : Type*) {V : Type*} [PartialOrder Γ] [Zero V] [SMul R V] :
HahnSeries Γ V ≃ HahnModule Γ R V := Equiv.refl _
@[elab_as_elim]
def rec {motive : HahnModule Γ R V → Sort*} (h : ∀ x : HahnSeries Γ V, motive (of R x)) :
∀ x, motive x :=
fun x => h <| (of R).symm x
@[ext]
theorem ext (x y : HahnModule Γ R V) (h : ((of R).symm x).coeff = ((of R).symm y).coeff) : x = y :=
(of R).symm.injective <| HahnSeries.coeff_inj.1 h
variable {V : Type*} [AddCommMonoid V] [SMul R V]
instance instAddCommMonoid : AddCommMonoid (HahnModule Γ R V) :=
inferInstanceAs <| AddCommMonoid (HahnSeries Γ V)
instance instBaseSMul {V} [Monoid R] [AddMonoid V] [DistribMulAction R V] :
SMul R (HahnModule Γ R V) :=
inferInstanceAs <| SMul R (HahnSeries Γ V)
instance instBaseModule [Semiring R] [Module R V] : Module R (HahnModule Γ R V) :=
inferInstanceAs <| Module R (HahnSeries Γ V)
@[simp] theorem of_zero : of R (0 : HahnSeries Γ V) = 0 := rfl
@[simp] theorem of_add (x y : HahnSeries Γ V) : of R (x + y) = of R x + of R y := rfl
@[simp] theorem of_symm_zero : (of R).symm (0 : HahnModule Γ R V) = 0 := rfl
@[simp] theorem of_symm_add (x y : HahnModule Γ R V) :
(of R).symm (x + y) = (of R).symm x + (of R).symm y := rfl
end
variable {Γ R V : Type*} [OrderedCancelAddCommMonoid Γ] [AddCommMonoid V] [SMul R V]
instance instSMul [Zero R] : SMul (HahnSeries Γ R) (HahnModule Γ R V) where
smul x y := {
coeff := fun a =>
∑ ij ∈ addAntidiagonal x.isPWO_support y.isPWO_support a,
x.coeff ij.fst • ((of R).symm y).coeff ij.snd
isPWO_support' :=
haveI h :
{a : Γ | ∑ ij ∈ addAntidiagonal x.isPWO_support y.isPWO_support a,
x.coeff ij.fst • y.coeff ij.snd ≠ 0} ⊆
{a : Γ | (addAntidiagonal x.isPWO_support y.isPWO_support a).Nonempty} := by
intro a ha
contrapose! ha
simp [not_nonempty_iff_eq_empty.1 ha]
isPWO_support_addAntidiagonal.mono h }
theorem smul_coeff [Zero R] (x : HahnSeries Γ R) (y : HahnModule Γ R V) (a : Γ) :
((of R).symm <| x • y).coeff a =
∑ ij ∈ addAntidiagonal x.isPWO_support y.isPWO_support a,
x.coeff ij.fst • ((of R).symm y).coeff ij.snd :=
rfl
variable {W : Type*} [Zero R] [AddCommMonoid W]
instance instSMulZeroClass [SMulZeroClass R W] :
SMulZeroClass (HahnSeries Γ R) (HahnModule Γ R W) where
smul_zero x := by
ext
simp [smul_coeff]
| Mathlib/RingTheory/HahnSeries/Multiplication.lean | 152 | 161 | theorem smul_coeff_right [SMulZeroClass R W] {x : HahnSeries Γ R}
{y : HahnModule Γ R W} {a : Γ} {s : Set Γ} (hs : s.IsPWO) (hys : ((of R).symm y).support ⊆ s) :
((of R).symm <| x • y).coeff a =
∑ ij ∈ addAntidiagonal x.isPWO_support hs a,
x.coeff ij.fst • ((of R).symm y).coeff ij.snd := by |
rw [smul_coeff]
apply sum_subset_zero_on_sdiff (addAntidiagonal_mono_right hys) _ fun _ _ => rfl
intro b hb
simp only [not_and, mem_sdiff, mem_addAntidiagonal, HahnSeries.mem_support, not_imp_not] at hb
rw [hb.2 hb.1.1 hb.1.2.2, smul_zero]
| 0 |
import Mathlib.Algebra.Polynomial.Cardinal
import Mathlib.Algebra.MvPolynomial.Cardinal
import Mathlib.Data.ZMod.Algebra
import Mathlib.FieldTheory.IsAlgClosed.Basic
import Mathlib.RingTheory.AlgebraicIndependent
#align_import field_theory.is_alg_closed.classification from "leanprover-community/mathlib"@"0723536a0522d24fc2f159a096fb3304bef77472"
universe u
open scoped Cardinal Polynomial
open Cardinal
section AlgebraicClosure
namespace Algebra.IsAlgebraic
variable (R L : Type u) [CommRing R] [CommRing L] [IsDomain L] [Algebra R L]
variable [NoZeroSMulDivisors R L] [Algebra.IsAlgebraic R L]
| Mathlib/FieldTheory/IsAlgClosed/Classification.lean | 41 | 59 | theorem cardinal_mk_le_sigma_polynomial :
#L ≤ #(Σ p : R[X], { x : L // x ∈ p.aroots L }) :=
@mk_le_of_injective L (Σ p : R[X], {x : L | x ∈ p.aroots L})
(fun x : L =>
let p := Classical.indefiniteDescription _ (Algebra.IsAlgebraic.isAlgebraic x)
⟨p.1, x, by
dsimp
have h : p.1.map (algebraMap R L) ≠ 0 := by |
rw [Ne, ← Polynomial.degree_eq_bot,
Polynomial.degree_map_eq_of_injective (NoZeroSMulDivisors.algebraMap_injective R L),
Polynomial.degree_eq_bot]
exact p.2.1
erw [Polynomial.mem_roots h, Polynomial.IsRoot, Polynomial.eval_map, ← Polynomial.aeval_def,
p.2.2]⟩)
fun x y => by
intro h
simp? at h says simp only [Set.coe_setOf, ne_eq, Set.mem_setOf_eq, Sigma.mk.inj_iff] at h
refine (Subtype.heq_iff_coe_eq ?_).1 h.2
simp only [h.1, iff_self_iff, forall_true_iff]
| 0 |
import Mathlib.Order.BooleanAlgebra
import Mathlib.Logic.Equiv.Basic
#align_import order.symm_diff from "leanprover-community/mathlib"@"6eb334bd8f3433d5b08ba156b8ec3e6af47e1904"
open Function OrderDual
variable {ι α β : Type*} {π : ι → Type*}
def symmDiff [Sup α] [SDiff α] (a b : α) : α :=
a \ b ⊔ b \ a
#align symm_diff symmDiff
def bihimp [Inf α] [HImp α] (a b : α) : α :=
(b ⇨ a) ⊓ (a ⇨ b)
#align bihimp bihimp
scoped[symmDiff] infixl:100 " ∆ " => symmDiff
scoped[symmDiff] infixl:100 " ⇔ " => bihimp
open scoped symmDiff
theorem symmDiff_def [Sup α] [SDiff α] (a b : α) : a ∆ b = a \ b ⊔ b \ a :=
rfl
#align symm_diff_def symmDiff_def
theorem bihimp_def [Inf α] [HImp α] (a b : α) : a ⇔ b = (b ⇨ a) ⊓ (a ⇨ b) :=
rfl
#align bihimp_def bihimp_def
theorem symmDiff_eq_Xor' (p q : Prop) : p ∆ q = Xor' p q :=
rfl
#align symm_diff_eq_xor symmDiff_eq_Xor'
@[simp]
theorem bihimp_iff_iff {p q : Prop} : p ⇔ q ↔ (p ↔ q) :=
(iff_iff_implies_and_implies _ _).symm.trans Iff.comm
#align bihimp_iff_iff bihimp_iff_iff
@[simp]
theorem Bool.symmDiff_eq_xor : ∀ p q : Bool, p ∆ q = xor p q := by decide
#align bool.symm_diff_eq_bxor Bool.symmDiff_eq_xor
section GeneralizedCoheytingAlgebra
variable [GeneralizedCoheytingAlgebra α] (a b c d : α)
@[simp]
theorem toDual_symmDiff : toDual (a ∆ b) = toDual a ⇔ toDual b :=
rfl
#align to_dual_symm_diff toDual_symmDiff
@[simp]
theorem ofDual_bihimp (a b : αᵒᵈ) : ofDual (a ⇔ b) = ofDual a ∆ ofDual b :=
rfl
#align of_dual_bihimp ofDual_bihimp
theorem symmDiff_comm : a ∆ b = b ∆ a := by simp only [symmDiff, sup_comm]
#align symm_diff_comm symmDiff_comm
instance symmDiff_isCommutative : Std.Commutative (α := α) (· ∆ ·) :=
⟨symmDiff_comm⟩
#align symm_diff_is_comm symmDiff_isCommutative
@[simp]
theorem symmDiff_self : a ∆ a = ⊥ := by rw [symmDiff, sup_idem, sdiff_self]
#align symm_diff_self symmDiff_self
@[simp]
theorem symmDiff_bot : a ∆ ⊥ = a := by rw [symmDiff, sdiff_bot, bot_sdiff, sup_bot_eq]
#align symm_diff_bot symmDiff_bot
@[simp]
theorem bot_symmDiff : ⊥ ∆ a = a := by rw [symmDiff_comm, symmDiff_bot]
#align bot_symm_diff bot_symmDiff
@[simp]
theorem symmDiff_eq_bot {a b : α} : a ∆ b = ⊥ ↔ a = b := by
simp_rw [symmDiff, sup_eq_bot_iff, sdiff_eq_bot_iff, le_antisymm_iff]
#align symm_diff_eq_bot symmDiff_eq_bot
theorem symmDiff_of_le {a b : α} (h : a ≤ b) : a ∆ b = b \ a := by
rw [symmDiff, sdiff_eq_bot_iff.2 h, bot_sup_eq]
#align symm_diff_of_le symmDiff_of_le
theorem symmDiff_of_ge {a b : α} (h : b ≤ a) : a ∆ b = a \ b := by
rw [symmDiff, sdiff_eq_bot_iff.2 h, sup_bot_eq]
#align symm_diff_of_ge symmDiff_of_ge
theorem symmDiff_le {a b c : α} (ha : a ≤ b ⊔ c) (hb : b ≤ a ⊔ c) : a ∆ b ≤ c :=
sup_le (sdiff_le_iff.2 ha) <| sdiff_le_iff.2 hb
#align symm_diff_le symmDiff_le
theorem symmDiff_le_iff {a b c : α} : a ∆ b ≤ c ↔ a ≤ b ⊔ c ∧ b ≤ a ⊔ c := by
simp_rw [symmDiff, sup_le_iff, sdiff_le_iff]
#align symm_diff_le_iff symmDiff_le_iff
@[simp]
theorem symmDiff_le_sup {a b : α} : a ∆ b ≤ a ⊔ b :=
sup_le_sup sdiff_le sdiff_le
#align symm_diff_le_sup symmDiff_le_sup
theorem symmDiff_eq_sup_sdiff_inf : a ∆ b = (a ⊔ b) \ (a ⊓ b) := by simp [sup_sdiff, symmDiff]
#align symm_diff_eq_sup_sdiff_inf symmDiff_eq_sup_sdiff_inf
theorem Disjoint.symmDiff_eq_sup {a b : α} (h : Disjoint a b) : a ∆ b = a ⊔ b := by
rw [symmDiff, h.sdiff_eq_left, h.sdiff_eq_right]
#align disjoint.symm_diff_eq_sup Disjoint.symmDiff_eq_sup
theorem symmDiff_sdiff : a ∆ b \ c = a \ (b ⊔ c) ⊔ b \ (a ⊔ c) := by
rw [symmDiff, sup_sdiff_distrib, sdiff_sdiff_left, sdiff_sdiff_left]
#align symm_diff_sdiff symmDiff_sdiff
@[simp]
theorem symmDiff_sdiff_inf : a ∆ b \ (a ⊓ b) = a ∆ b := by
rw [symmDiff_sdiff]
simp [symmDiff]
#align symm_diff_sdiff_inf symmDiff_sdiff_inf
@[simp]
| Mathlib/Order/SymmDiff.lean | 176 | 180 | theorem symmDiff_sdiff_eq_sup : a ∆ (b \ a) = a ⊔ b := by |
rw [symmDiff, sdiff_idem]
exact
le_antisymm (sup_le_sup sdiff_le sdiff_le)
(sup_le le_sdiff_sup <| le_sdiff_sup.trans <| sup_le le_sup_right le_sdiff_sup)
| 0 |
import Mathlib.Dynamics.Ergodic.AddCircle
import Mathlib.MeasureTheory.Covering.LiminfLimsup
#align_import number_theory.well_approximable from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
open Set Filter Function Metric MeasureTheory
open scoped MeasureTheory Topology Pointwise
@[to_additive "In a seminormed additive group `A`, given `n : ℕ` and `δ : ℝ`,
`approxAddOrderOf A n δ` is the set of elements within a distance `δ` of a point of order `n`."]
def approxOrderOf (A : Type*) [SeminormedGroup A] (n : ℕ) (δ : ℝ) : Set A :=
thickening δ {y | orderOf y = n}
#align approx_order_of approxOrderOf
#align approx_add_order_of approxAddOrderOf
@[to_additive mem_approx_add_orderOf_iff]
theorem mem_approxOrderOf_iff {A : Type*} [SeminormedGroup A] {n : ℕ} {δ : ℝ} {a : A} :
a ∈ approxOrderOf A n δ ↔ ∃ b : A, orderOf b = n ∧ a ∈ ball b δ := by
simp only [approxOrderOf, thickening_eq_biUnion_ball, mem_iUnion₂, mem_setOf_eq, exists_prop]
#align mem_approx_order_of_iff mem_approxOrderOf_iff
#align mem_approx_add_order_of_iff mem_approx_add_orderOf_iff
@[to_additive addWellApproximable "In a seminormed additive group `A`, given a sequence of
distances `δ₁, δ₂, ...`, `addWellApproximable A δ` is the limsup as `n → ∞` of the sets
`approxAddOrderOf A n δₙ`. Thus, it is the set of points that lie in infinitely many of the sets
`approxAddOrderOf A n δₙ`."]
def wellApproximable (A : Type*) [SeminormedGroup A] (δ : ℕ → ℝ) : Set A :=
blimsup (fun n => approxOrderOf A n (δ n)) atTop fun n => 0 < n
#align well_approximable wellApproximable
#align add_well_approximable addWellApproximable
@[to_additive mem_add_wellApproximable_iff]
theorem mem_wellApproximable_iff {A : Type*} [SeminormedGroup A] {δ : ℕ → ℝ} {a : A} :
a ∈ wellApproximable A δ ↔
a ∈ blimsup (fun n => approxOrderOf A n (δ n)) atTop fun n => 0 < n :=
Iff.rfl
#align mem_well_approximable_iff mem_wellApproximable_iff
#align mem_add_well_approximable_iff mem_add_wellApproximable_iff
namespace UnitAddCircle
| Mathlib/NumberTheory/WellApproximable.lean | 174 | 180 | theorem mem_approxAddOrderOf_iff {δ : ℝ} {x : UnitAddCircle} {n : ℕ} (hn : 0 < n) :
x ∈ approxAddOrderOf UnitAddCircle n δ ↔ ∃ m < n, gcd m n = 1 ∧ ‖x - ↑((m : ℝ) / n)‖ < δ := by |
simp only [mem_approx_add_orderOf_iff, mem_setOf_eq, ball, exists_prop, dist_eq_norm,
AddCircle.addOrderOf_eq_pos_iff hn, mul_one]
constructor
· rintro ⟨y, ⟨m, hm₁, hm₂, rfl⟩, hx⟩; exact ⟨m, hm₁, hm₂, hx⟩
· rintro ⟨m, hm₁, hm₂, hx⟩; exact ⟨↑((m : ℝ) / n), ⟨m, hm₁, hm₂, rfl⟩, hx⟩
| 0 |
import Mathlib.ModelTheory.Algebra.Ring.Basic
import Mathlib.RingTheory.FreeCommRing
namespace FirstOrder
namespace Ring
open Language
variable {α : Type*}
section
attribute [local instance] compatibleRingOfRing
private theorem exists_term_realize_eq_freeCommRing (p : FreeCommRing α) :
∃ t : Language.ring.Term α,
(t.realize FreeCommRing.of : FreeCommRing α) = p :=
FreeCommRing.induction_on p
⟨-1, by simp [Term.realize]⟩
(fun a => ⟨Term.var a, by simp [Term.realize]⟩)
(fun x y ⟨t₁, ht₁⟩ ⟨t₂, ht₂⟩ =>
⟨t₁ + t₂, by simp_all [Term.realize]⟩)
(fun x y ⟨t₁, ht₁⟩ ⟨t₂, ht₂⟩ =>
⟨t₁ * t₂, by simp_all [Term.realize]⟩)
end
noncomputable def termOfFreeCommRing (p : FreeCommRing α) : Language.ring.Term α :=
Classical.choose (exists_term_realize_eq_freeCommRing p)
variable {R : Type*} [CommRing R] [CompatibleRing R]
@[simp]
| Mathlib/ModelTheory/Algebra/Ring/FreeCommRing.lean | 54 | 63 | theorem realize_termOfFreeCommRing (p : FreeCommRing α) (v : α → R) :
(termOfFreeCommRing p).realize v = FreeCommRing.lift v p := by |
let _ := compatibleRingOfRing (FreeCommRing α)
rw [termOfFreeCommRing]
conv_rhs => rw [← Classical.choose_spec (exists_term_realize_eq_freeCommRing p)]
induction Classical.choose (exists_term_realize_eq_freeCommRing p) with
| var _ => simp
| func f a ih =>
cases f <;>
simp [ih]
| 0 |
import Mathlib.MeasureTheory.Constructions.BorelSpace.Order
#align_import measure_theory.function.ae_measurable_order from "leanprover-community/mathlib"@"bf6a01357ff5684b1ebcd0f1a13be314fc82c0bf"
open MeasureTheory Set TopologicalSpace
open scoped Classical
open ENNReal NNReal
| Mathlib/MeasureTheory/Function/AEMeasurableOrder.lean | 34 | 107 | theorem MeasureTheory.aemeasurable_of_exist_almost_disjoint_supersets {α : Type*}
{m : MeasurableSpace α} (μ : Measure α) {β : Type*} [CompleteLinearOrder β] [DenselyOrdered β]
[TopologicalSpace β] [OrderTopology β] [SecondCountableTopology β] [MeasurableSpace β]
[BorelSpace β] (s : Set β) (s_count : s.Countable) (s_dense : Dense s) (f : α → β)
(h : ∀ p ∈ s, ∀ q ∈ s, p < q → ∃ u v, MeasurableSet u ∧ MeasurableSet v ∧
{ x | f x < p } ⊆ u ∧ { x | q < f x } ⊆ v ∧ μ (u ∩ v) = 0) :
AEMeasurable f μ := by |
haveI : Encodable s := s_count.toEncodable
have h' : ∀ p q, ∃ u v, MeasurableSet u ∧ MeasurableSet v ∧
{ x | f x < p } ⊆ u ∧ { x | q < f x } ⊆ v ∧ (p ∈ s → q ∈ s → p < q → μ (u ∩ v) = 0) := by
intro p q
by_cases H : p ∈ s ∧ q ∈ s ∧ p < q
· rcases h p H.1 q H.2.1 H.2.2 with ⟨u, v, hu, hv, h'u, h'v, hμ⟩
exact ⟨u, v, hu, hv, h'u, h'v, fun _ _ _ => hμ⟩
· refine
⟨univ, univ, MeasurableSet.univ, MeasurableSet.univ, subset_univ _, subset_univ _,
fun ps qs pq => ?_⟩
simp only [not_and] at H
exact (H ps qs pq).elim
choose! u v huv using h'
let u' : β → Set α := fun p => ⋂ q ∈ s ∩ Ioi p, u p q
have u'_meas : ∀ i, MeasurableSet (u' i) := by
intro i
exact MeasurableSet.biInter (s_count.mono inter_subset_left) fun b _ => (huv i b).1
let f' : α → β := fun x => ⨅ i : s, piecewise (u' i) (fun _ => (i : β)) (fun _ => (⊤ : β)) x
have f'_meas : Measurable f' := by
apply measurable_iInf
exact fun i => Measurable.piecewise (u'_meas i) measurable_const measurable_const
let t := ⋃ (p : s) (q : ↥(s ∩ Ioi p)), u' p ∩ v p q
have μt : μ t ≤ 0 :=
calc
μ t ≤ ∑' (p : s) (q : ↥(s ∩ Ioi p)), μ (u' p ∩ v p q) := by
refine (measure_iUnion_le _).trans ?_
refine ENNReal.tsum_le_tsum fun p => ?_
haveI := (s_count.mono (s.inter_subset_left (t := Ioi ↑p))).to_subtype
apply measure_iUnion_le
_ ≤ ∑' (p : s) (q : ↥(s ∩ Ioi p)), μ (u p q ∩ v p q) := by
gcongr with p q
exact biInter_subset_of_mem q.2
_ = ∑' (p : s) (_ : ↥(s ∩ Ioi p)), (0 : ℝ≥0∞) := by
congr
ext1 p
congr
ext1 q
exact (huv p q).2.2.2.2 p.2 q.2.1 q.2.2
_ = 0 := by simp only [tsum_zero]
have ff' : ∀ᵐ x ∂μ, f x = f' x := by
have : ∀ᵐ x ∂μ, x ∉ t := by
have : μ t = 0 := le_antisymm μt bot_le
change μ _ = 0
convert this
ext y
simp only [not_exists, exists_prop, mem_setOf_eq, mem_compl_iff, not_not_mem]
filter_upwards [this] with x hx
apply (iInf_eq_of_forall_ge_of_forall_gt_exists_lt _ _).symm
· intro i
by_cases H : x ∈ u' i
swap
· simp only [H, le_top, not_false_iff, piecewise_eq_of_not_mem]
simp only [H, piecewise_eq_of_mem]
contrapose! hx
obtain ⟨r, ⟨xr, rq⟩, rs⟩ : ∃ r, r ∈ Ioo (i : β) (f x) ∩ s :=
dense_iff_inter_open.1 s_dense (Ioo i (f x)) isOpen_Ioo (nonempty_Ioo.2 hx)
have A : x ∈ v i r := (huv i r).2.2.2.1 rq
refine mem_iUnion.2 ⟨i, ?_⟩
refine mem_iUnion.2 ⟨⟨r, ⟨rs, xr⟩⟩, ?_⟩
exact ⟨H, A⟩
· intro q hq
obtain ⟨r, ⟨xr, rq⟩, rs⟩ : ∃ r, r ∈ Ioo (f x) q ∩ s :=
dense_iff_inter_open.1 s_dense (Ioo (f x) q) isOpen_Ioo (nonempty_Ioo.2 hq)
refine ⟨⟨r, rs⟩, ?_⟩
have A : x ∈ u' r := mem_biInter fun i _ => (huv r i).2.2.1 xr
simp only [A, rq, piecewise_eq_of_mem, Subtype.coe_mk]
exact ⟨f', f'_meas, ff'⟩
| 0 |
import Mathlib.CategoryTheory.CofilteredSystem
import Mathlib.Combinatorics.SimpleGraph.Subgraph
#align_import combinatorics.simple_graph.finsubgraph from "leanprover-community/mathlib"@"c6ef6387ede9983aee397d442974e61f89dfd87b"
open Set CategoryTheory
universe u v
variable {V : Type u} {W : Type v} {G : SimpleGraph V} {F : SimpleGraph W}
namespace SimpleGraph
abbrev Finsubgraph (G : SimpleGraph V) :=
{ G' : G.Subgraph // G'.verts.Finite }
#align simple_graph.finsubgraph SimpleGraph.Finsubgraph
abbrev FinsubgraphHom (G' : G.Finsubgraph) (F : SimpleGraph W) :=
G'.val.coe →g F
#align simple_graph.finsubgraph_hom SimpleGraph.FinsubgraphHom
local infixl:50 " →fg " => FinsubgraphHom
instance : OrderBot G.Finsubgraph where
bot := ⟨⊥, finite_empty⟩
bot_le _ := bot_le (α := G.Subgraph)
instance : Sup G.Finsubgraph :=
⟨fun G₁ G₂ => ⟨G₁ ⊔ G₂, G₁.2.union G₂.2⟩⟩
instance : Inf G.Finsubgraph :=
⟨fun G₁ G₂ => ⟨G₁ ⊓ G₂, G₁.2.subset inter_subset_left⟩⟩
instance : DistribLattice G.Finsubgraph :=
Subtype.coe_injective.distribLattice _ (fun _ _ => rfl) fun _ _ => rfl
instance [Finite V] : Top G.Finsubgraph :=
⟨⟨⊤, finite_univ⟩⟩
instance [Finite V] : SupSet G.Finsubgraph :=
⟨fun s => ⟨⨆ G ∈ s, ↑G, Set.toFinite _⟩⟩
instance [Finite V] : InfSet G.Finsubgraph :=
⟨fun s => ⟨⨅ G ∈ s, ↑G, Set.toFinite _⟩⟩
instance [Finite V] : CompletelyDistribLattice G.Finsubgraph :=
Subtype.coe_injective.completelyDistribLattice _ (fun _ _ => rfl) (fun _ _ => rfl) (fun _ => rfl)
(fun _ => rfl) rfl rfl
def singletonFinsubgraph (v : V) : G.Finsubgraph :=
⟨SimpleGraph.singletonSubgraph _ v, by simp⟩
#align simple_graph.singleton_finsubgraph SimpleGraph.singletonFinsubgraph
def finsubgraphOfAdj {u v : V} (e : G.Adj u v) : G.Finsubgraph :=
⟨SimpleGraph.subgraphOfAdj _ e, by simp⟩
#align simple_graph.finsubgraph_of_adj SimpleGraph.finsubgraphOfAdj
-- Lemmas establishing the ordering between edge- and vertex-generated subgraphs.
theorem singletonFinsubgraph_le_adj_left {u v : V} {e : G.Adj u v} :
singletonFinsubgraph u ≤ finsubgraphOfAdj e := by
simp [singletonFinsubgraph, finsubgraphOfAdj]
#align simple_graph.singleton_finsubgraph_le_adj_left SimpleGraph.singletonFinsubgraph_le_adj_left
theorem singletonFinsubgraph_le_adj_right {u v : V} {e : G.Adj u v} :
singletonFinsubgraph v ≤ finsubgraphOfAdj e := by
simp [singletonFinsubgraph, finsubgraphOfAdj]
#align simple_graph.singleton_finsubgraph_le_adj_right SimpleGraph.singletonFinsubgraph_le_adj_right
def FinsubgraphHom.restrict {G' G'' : G.Finsubgraph} (h : G'' ≤ G') (f : G' →fg F) : G'' →fg F := by
refine ⟨fun ⟨v, hv⟩ => f.toFun ⟨v, h.1 hv⟩, ?_⟩
rintro ⟨u, hu⟩ ⟨v, hv⟩ huv
exact f.map_rel' (h.2 huv)
#align simple_graph.finsubgraph_hom.restrict SimpleGraph.FinsubgraphHom.restrict
def finsubgraphHomFunctor (G : SimpleGraph V) (F : SimpleGraph W) :
G.Finsubgraphᵒᵖ ⥤ Type max u v where
obj G' := G'.unop →fg F
map g f := f.restrict (CategoryTheory.leOfHom g.unop)
#align simple_graph.finsubgraph_hom_functor SimpleGraph.finsubgraphHomFunctor
| Mathlib/Combinatorics/SimpleGraph/Finsubgraph.lean | 119 | 153 | theorem nonempty_hom_of_forall_finite_subgraph_hom [Finite W]
(h : ∀ G' : G.Subgraph, G'.verts.Finite → G'.coe →g F) : Nonempty (G →g F) := by |
-- Obtain a `Fintype` instance for `W`.
cases nonempty_fintype W
-- Establish the required interface instances.
haveI : ∀ G' : G.Finsubgraphᵒᵖ, Nonempty ((finsubgraphHomFunctor G F).obj G') := fun G' =>
⟨h G'.unop G'.unop.property⟩
haveI : ∀ G' : G.Finsubgraphᵒᵖ, Fintype ((finsubgraphHomFunctor G F).obj G') := by
intro G'
haveI : Fintype (G'.unop.val.verts : Type u) := G'.unop.property.fintype
haveI : Fintype (↥G'.unop.val.verts → W) := by classical exact Pi.fintype
exact Fintype.ofInjective (fun f => f.toFun) RelHom.coe_fn_injective
-- Use compactness to obtain a section.
obtain ⟨u, hu⟩ := nonempty_sections_of_finite_inverse_system (finsubgraphHomFunctor G F)
refine ⟨⟨fun v => ?_, ?_⟩⟩
· -- Map each vertex using the homomorphism provided for its singleton subgraph.
exact
(u (Opposite.op (singletonFinsubgraph v))).toFun
⟨v, by
unfold singletonFinsubgraph
simp⟩
· -- Prove that the above mapping preserves adjacency.
intro v v' e
simp only
/- The homomorphism for each edge's singleton subgraph agrees with those for its source and
target vertices. -/
have hv : Opposite.op (finsubgraphOfAdj e) ⟶ Opposite.op (singletonFinsubgraph v) :=
Quiver.Hom.op (CategoryTheory.homOfLE singletonFinsubgraph_le_adj_left)
have hv' : Opposite.op (finsubgraphOfAdj e) ⟶ Opposite.op (singletonFinsubgraph v') :=
Quiver.Hom.op (CategoryTheory.homOfLE singletonFinsubgraph_le_adj_right)
rw [← hu hv, ← hu hv']
-- Porting note: was `apply Hom.map_adj`
refine Hom.map_adj (u (Opposite.op (finsubgraphOfAdj e))) ?_
-- `v` and `v'` are definitionally adjacent in `finsubgraphOfAdj e`
simp [finsubgraphOfAdj]
| 0 |
import Mathlib.CategoryTheory.Limits.Shapes.Biproducts
import Mathlib.GroupTheory.EckmannHilton
import Mathlib.Tactic.CategoryTheory.Reassoc
#align_import category_theory.preadditive.of_biproducts from "leanprover-community/mathlib"@"061ea99a5610cfc72c286aa930d3c1f47f74f3d0"
noncomputable section
universe v u
open CategoryTheory
open CategoryTheory.Limits
namespace CategoryTheory.SemiadditiveOfBinaryBiproducts
variable {C : Type u} [Category.{v} C] [HasZeroMorphisms C] [HasBinaryBiproducts C]
section
variable (X Y : C)
@[simp]
def leftAdd (f g : X ⟶ Y) : X ⟶ Y :=
biprod.lift f g ≫ biprod.desc (𝟙 Y) (𝟙 Y)
#align category_theory.semiadditive_of_binary_biproducts.left_add CategoryTheory.SemiadditiveOfBinaryBiproducts.leftAdd
@[simp]
def rightAdd (f g : X ⟶ Y) : X ⟶ Y :=
biprod.lift (𝟙 X) (𝟙 X) ≫ biprod.desc f g
#align category_theory.semiadditive_of_binary_biproducts.right_add CategoryTheory.SemiadditiveOfBinaryBiproducts.rightAdd
local infixr:65 " +ₗ " => leftAdd X Y
local infixr:65 " +ᵣ " => rightAdd X Y
theorem isUnital_leftAdd : EckmannHilton.IsUnital (· +ₗ ·) 0 := by
have hr : ∀ f : X ⟶ Y, biprod.lift (0 : X ⟶ Y) f = f ≫ biprod.inr := by
intro f
ext
· aesop_cat
· simp [biprod.lift_fst, Category.assoc, biprod.inr_fst, comp_zero]
have hl : ∀ f : X ⟶ Y, biprod.lift f (0 : X ⟶ Y) = f ≫ biprod.inl := by
intro f
ext
· aesop_cat
· simp [biprod.lift_snd, Category.assoc, biprod.inl_snd, comp_zero]
exact {
left_id := fun f => by simp [hr f, leftAdd, Category.assoc, Category.comp_id, biprod.inr_desc],
right_id := fun f => by simp [hl f, leftAdd, Category.assoc, Category.comp_id, biprod.inl_desc]
}
#align category_theory.semiadditive_of_binary_biproducts.is_unital_left_add CategoryTheory.SemiadditiveOfBinaryBiproducts.isUnital_leftAdd
theorem isUnital_rightAdd : EckmannHilton.IsUnital (· +ᵣ ·) 0 := by
have h₂ : ∀ f : X ⟶ Y, biprod.desc (0 : X ⟶ Y) f = biprod.snd ≫ f := by
intro f
ext
· aesop_cat
· simp only [biprod.inr_desc, BinaryBicone.inr_snd_assoc]
have h₁ : ∀ f : X ⟶ Y, biprod.desc f (0 : X ⟶ Y) = biprod.fst ≫ f := by
intro f
ext
· aesop_cat
· simp only [biprod.inr_desc, BinaryBicone.inr_fst_assoc, zero_comp]
exact {
left_id := fun f => by simp [h₂ f, rightAdd, biprod.lift_snd_assoc, Category.id_comp],
right_id := fun f => by simp [h₁ f, rightAdd, biprod.lift_fst_assoc, Category.id_comp]
}
#align category_theory.semiadditive_of_binary_biproducts.is_unital_right_add CategoryTheory.SemiadditiveOfBinaryBiproducts.isUnital_rightAdd
| Mathlib/CategoryTheory/Preadditive/OfBiproducts.lean | 88 | 96 | theorem distrib (f g h k : X ⟶ Y) : (f +ᵣ g) +ₗ h +ᵣ k = (f +ₗ h) +ᵣ g +ₗ k := by |
let diag : X ⊞ X ⟶ Y ⊞ Y := biprod.lift (biprod.desc f g) (biprod.desc h k)
have hd₁ : biprod.inl ≫ diag = biprod.lift f h := by ext <;> simp [diag]
have hd₂ : biprod.inr ≫ diag = biprod.lift g k := by ext <;> simp [diag]
have h₁ : biprod.lift (f +ᵣ g) (h +ᵣ k) = biprod.lift (𝟙 X) (𝟙 X) ≫ diag := by
ext <;> aesop_cat
have h₂ : diag ≫ biprod.desc (𝟙 Y) (𝟙 Y) = biprod.desc (f +ₗ h) (g +ₗ k) := by
ext <;> simp [reassoc_of% hd₁, reassoc_of% hd₂]
rw [leftAdd, h₁, Category.assoc, h₂, rightAdd]
| 0 |
import Mathlib.Topology.PartitionOfUnity
import Mathlib.Analysis.Convex.Combination
#align_import analysis.convex.partition_of_unity from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open Set Function
open Topology
variable {ι X E : Type*} [TopologicalSpace X] [AddCommGroup E] [Module ℝ E]
theorem PartitionOfUnity.finsum_smul_mem_convex {s : Set X} (f : PartitionOfUnity ι X s)
{g : ι → X → E} {t : Set E} {x : X} (hx : x ∈ s) (hg : ∀ i, f i x ≠ 0 → g i x ∈ t)
(ht : Convex ℝ t) : (∑ᶠ i, f i x • g i x) ∈ t :=
ht.finsum_mem (fun _ => f.nonneg _ _) (f.sum_eq_one hx) hg
#align partition_of_unity.finsum_smul_mem_convex PartitionOfUnity.finsum_smul_mem_convex
variable [NormalSpace X] [ParacompactSpace X] [TopologicalSpace E] [ContinuousAdd E]
[ContinuousSMul ℝ E] {t : X → Set E}
| Mathlib/Analysis/Convex/PartitionOfUnity.lean | 51 | 60 | theorem exists_continuous_forall_mem_convex_of_local (ht : ∀ x, Convex ℝ (t x))
(H : ∀ x : X, ∃ U ∈ 𝓝 x, ∃ g : X → E, ContinuousOn g U ∧ ∀ y ∈ U, g y ∈ t y) :
∃ g : C(X, E), ∀ x, g x ∈ t x := by |
choose U hU g hgc hgt using H
obtain ⟨f, hf⟩ := PartitionOfUnity.exists_isSubordinate isClosed_univ (fun x => interior (U x))
(fun x => isOpen_interior) fun x _ => mem_iUnion.2 ⟨x, mem_interior_iff_mem_nhds.2 (hU x)⟩
refine ⟨⟨fun x => ∑ᶠ i, f i x • g i x,
hf.continuous_finsum_smul (fun i => isOpen_interior) fun i => (hgc i).mono interior_subset⟩,
fun x => f.finsum_smul_mem_convex (mem_univ x) (fun i hi => hgt _ _ ?_) (ht _)⟩
exact interior_subset (hf _ <| subset_closure hi)
| 0 |
import Mathlib.Logic.Equiv.Defs
#align_import data.erased from "leanprover-community/mathlib"@"10b4e499f43088dd3bb7b5796184ad5216648ab1"
universe u
def Erased (α : Sort u) : Sort max 1 u :=
Σ's : α → Prop, ∃ a, (fun b => a = b) = s
#align erased Erased
namespace Erased
@[inline]
def mk {α} (a : α) : Erased α :=
⟨fun b => a = b, a, rfl⟩
#align erased.mk Erased.mk
noncomputable def out {α} : Erased α → α
| ⟨_, h⟩ => Classical.choose h
#align erased.out Erased.out
abbrev OutType (a : Erased (Sort u)) : Sort u :=
out a
#align erased.out_type Erased.OutType
theorem out_proof {p : Prop} (a : Erased p) : p :=
out a
#align erased.out_proof Erased.out_proof
@[simp]
| Mathlib/Data/Erased.lean | 56 | 59 | theorem out_mk {α} (a : α) : (mk a).out = a := by |
let h := (mk a).2; show Classical.choose h = a
have := Classical.choose_spec h
exact cast (congr_fun this a).symm rfl
| 0 |
import Mathlib.Analysis.Calculus.Deriv.Basic
import Mathlib.Analysis.Calculus.Deriv.Slope
import Mathlib.Analysis.NormedSpace.FiniteDimension
import Mathlib.MeasureTheory.Constructions.BorelSpace.ContinuousLinearMap
import Mathlib.MeasureTheory.Function.StronglyMeasurable.Basic
#align_import analysis.calculus.fderiv_measurable from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe"
set_option linter.uppercaseLean3 false -- A B D
noncomputable section
open Set Metric Asymptotics Filter ContinuousLinearMap MeasureTheory TopologicalSpace
open scoped Topology
section fderiv
variable {𝕜 : Type*} [NontriviallyNormedField 𝕜]
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace 𝕜 E]
variable {F : Type*} [NormedAddCommGroup F] [NormedSpace 𝕜 F]
variable {f : E → F} (K : Set (E →L[𝕜] F))
namespace FDerivMeasurableAux
def A (f : E → F) (L : E →L[𝕜] F) (r ε : ℝ) : Set E :=
{ x | ∃ r' ∈ Ioc (r / 2) r, ∀ y ∈ ball x r', ∀ z ∈ ball x r', ‖f z - f y - L (z - y)‖ < ε * r }
#align fderiv_measurable_aux.A FDerivMeasurableAux.A
def B (f : E → F) (K : Set (E →L[𝕜] F)) (r s ε : ℝ) : Set E :=
⋃ L ∈ K, A f L r ε ∩ A f L s ε
#align fderiv_measurable_aux.B FDerivMeasurableAux.B
def D (f : E → F) (K : Set (E →L[𝕜] F)) : Set E :=
⋂ e : ℕ, ⋃ n : ℕ, ⋂ (p ≥ n) (q ≥ n), B f K ((1 / 2) ^ p) ((1 / 2) ^ q) ((1 / 2) ^ e)
#align fderiv_measurable_aux.D FDerivMeasurableAux.D
theorem isOpen_A (L : E →L[𝕜] F) (r ε : ℝ) : IsOpen (A f L r ε) := by
rw [Metric.isOpen_iff]
rintro x ⟨r', r'_mem, hr'⟩
obtain ⟨s, s_gt, s_lt⟩ : ∃ s : ℝ, r / 2 < s ∧ s < r' := exists_between r'_mem.1
have : s ∈ Ioc (r / 2) r := ⟨s_gt, le_of_lt (s_lt.trans_le r'_mem.2)⟩
refine ⟨r' - s, by linarith, fun x' hx' => ⟨s, this, ?_⟩⟩
have B : ball x' s ⊆ ball x r' := ball_subset (le_of_lt hx')
intro y hy z hz
exact hr' y (B hy) z (B hz)
#align fderiv_measurable_aux.is_open_A FDerivMeasurableAux.isOpen_A
theorem isOpen_B {K : Set (E →L[𝕜] F)} {r s ε : ℝ} : IsOpen (B f K r s ε) := by
simp [B, isOpen_biUnion, IsOpen.inter, isOpen_A]
#align fderiv_measurable_aux.is_open_B FDerivMeasurableAux.isOpen_B
theorem A_mono (L : E →L[𝕜] F) (r : ℝ) {ε δ : ℝ} (h : ε ≤ δ) : A f L r ε ⊆ A f L r δ := by
rintro x ⟨r', r'r, hr'⟩
refine ⟨r', r'r, fun y hy z hz => (hr' y hy z hz).trans_le (mul_le_mul_of_nonneg_right h ?_)⟩
linarith [mem_ball.1 hy, r'r.2, @dist_nonneg _ _ y x]
#align fderiv_measurable_aux.A_mono FDerivMeasurableAux.A_mono
theorem le_of_mem_A {r ε : ℝ} {L : E →L[𝕜] F} {x : E} (hx : x ∈ A f L r ε) {y z : E}
(hy : y ∈ closedBall x (r / 2)) (hz : z ∈ closedBall x (r / 2)) :
‖f z - f y - L (z - y)‖ ≤ ε * r := by
rcases hx with ⟨r', r'mem, hr'⟩
apply le_of_lt
exact hr' _ ((mem_closedBall.1 hy).trans_lt r'mem.1) _ ((mem_closedBall.1 hz).trans_lt r'mem.1)
#align fderiv_measurable_aux.le_of_mem_A FDerivMeasurableAux.le_of_mem_A
| Mathlib/Analysis/Calculus/FDeriv/Measurable.lean | 162 | 181 | theorem mem_A_of_differentiable {ε : ℝ} (hε : 0 < ε) {x : E} (hx : DifferentiableAt 𝕜 f x) :
∃ R > 0, ∀ r ∈ Ioo (0 : ℝ) R, x ∈ A f (fderiv 𝕜 f x) r ε := by |
let δ := (ε / 2) / 2
obtain ⟨R, R_pos, hR⟩ :
∃ R > 0, ∀ y ∈ ball x R, ‖f y - f x - fderiv 𝕜 f x (y - x)‖ ≤ δ * ‖y - x‖ :=
eventually_nhds_iff_ball.1 <| hx.hasFDerivAt.isLittleO.bound <| by positivity
refine ⟨R, R_pos, fun r hr => ?_⟩
have : r ∈ Ioc (r / 2) r := right_mem_Ioc.2 <| half_lt_self hr.1
refine ⟨r, this, fun y hy z hz => ?_⟩
calc
‖f z - f y - (fderiv 𝕜 f x) (z - y)‖ =
‖f z - f x - (fderiv 𝕜 f x) (z - x) - (f y - f x - (fderiv 𝕜 f x) (y - x))‖ := by
simp only [map_sub]; abel_nf
_ ≤ ‖f z - f x - (fderiv 𝕜 f x) (z - x)‖ + ‖f y - f x - (fderiv 𝕜 f x) (y - x)‖ :=
norm_sub_le _ _
_ ≤ δ * ‖z - x‖ + δ * ‖y - x‖ :=
add_le_add (hR _ (ball_subset_ball hr.2.le hz)) (hR _ (ball_subset_ball hr.2.le hy))
_ ≤ δ * r + δ * r := by rw [mem_ball_iff_norm] at hz hy; gcongr
_ = (ε / 2) * r := by ring
_ < ε * r := by gcongr; exacts [hr.1, half_lt_self hε]
| 0 |
import Mathlib.Algebra.GroupWithZero.Units.Basic
import Mathlib.Algebra.Group.Semiconj.Units
import Mathlib.Init.Classical
#align_import algebra.group_with_zero.semiconj from "leanprover-community/mathlib"@"70d50ecfd4900dd6d328da39ab7ebd516abe4025"
assert_not_exists DenselyOrdered
variable {α M₀ G₀ M₀' G₀' F F' : Type*}
namespace SemiconjBy
@[simp]
theorem zero_right [MulZeroClass G₀] (a : G₀) : SemiconjBy a 0 0 := by
simp only [SemiconjBy, mul_zero, zero_mul]
#align semiconj_by.zero_right SemiconjBy.zero_right
@[simp]
theorem zero_left [MulZeroClass G₀] (x y : G₀) : SemiconjBy 0 x y := by
simp only [SemiconjBy, mul_zero, zero_mul]
#align semiconj_by.zero_left SemiconjBy.zero_left
variable [GroupWithZero G₀] {a x y x' y' : G₀}
@[simp]
theorem inv_symm_left_iff₀ : SemiconjBy a⁻¹ x y ↔ SemiconjBy a y x :=
Classical.by_cases (fun ha : a = 0 => by simp only [ha, inv_zero, SemiconjBy.zero_left]) fun ha =>
@units_inv_symm_left_iff _ _ (Units.mk0 a ha) _ _
#align semiconj_by.inv_symm_left_iff₀ SemiconjBy.inv_symm_left_iff₀
theorem inv_symm_left₀ (h : SemiconjBy a x y) : SemiconjBy a⁻¹ y x :=
SemiconjBy.inv_symm_left_iff₀.2 h
#align semiconj_by.inv_symm_left₀ SemiconjBy.inv_symm_left₀
| Mathlib/Algebra/GroupWithZero/Semiconj.lean | 45 | 54 | theorem inv_right₀ (h : SemiconjBy a x y) : SemiconjBy a x⁻¹ y⁻¹ := by |
by_cases ha : a = 0
· simp only [ha, zero_left]
by_cases hx : x = 0
· subst x
simp only [SemiconjBy, mul_zero, @eq_comm _ _ (y * a), mul_eq_zero] at h
simp [h.resolve_right ha]
· have := mul_ne_zero ha hx
rw [h.eq, mul_ne_zero_iff] at this
exact @units_inv_right _ _ _ (Units.mk0 x hx) (Units.mk0 y this.1) h
| 0 |
import Mathlib.GroupTheory.Perm.Cycle.Basic
#align_import group_theory.perm.cycle.basic from "leanprover-community/mathlib"@"e8638a0fcaf73e4500469f368ef9494e495099b3"
open Equiv Function Finset
variable {ι α β : Type*}
namespace Equiv.Perm
section Generation
variable [Finite β]
open Subgroup
| Mathlib/GroupTheory/Perm/Closure.lean | 37 | 41 | theorem closure_isCycle : closure { σ : Perm β | IsCycle σ } = ⊤ := by |
classical
cases nonempty_fintype β
exact
top_le_iff.mp (le_trans (ge_of_eq closure_isSwap) (closure_mono fun _ => IsSwap.isCycle))
| 0 |
import Mathlib.Analysis.Convolution
import Mathlib.Analysis.SpecialFunctions.Trigonometric.EulerSineProd
import Mathlib.Analysis.SpecialFunctions.Gamma.BohrMollerup
import Mathlib.Analysis.Analytic.IsolatedZeros
import Mathlib.Analysis.Complex.CauchyIntegral
#align_import analysis.special_functions.gamma.beta from "leanprover-community/mathlib"@"a3209ddf94136d36e5e5c624b10b2a347cc9d090"
noncomputable section
set_option linter.uppercaseLean3 false
open Filter intervalIntegral Set Real MeasureTheory
open scoped Nat Topology Real
section BetaIntegral
namespace Complex
noncomputable def betaIntegral (u v : ℂ) : ℂ :=
∫ x : ℝ in (0)..1, (x : ℂ) ^ (u - 1) * (1 - (x : ℂ)) ^ (v - 1)
#align complex.beta_integral Complex.betaIntegral
theorem betaIntegral_convergent_left {u : ℂ} (hu : 0 < re u) (v : ℂ) :
IntervalIntegrable (fun x =>
(x : ℂ) ^ (u - 1) * (1 - (x : ℂ)) ^ (v - 1) : ℝ → ℂ) volume 0 (1 / 2) := by
apply IntervalIntegrable.mul_continuousOn
· refine intervalIntegral.intervalIntegrable_cpow' ?_
rwa [sub_re, one_re, ← zero_sub, sub_lt_sub_iff_right]
· apply ContinuousAt.continuousOn
intro x hx
rw [uIcc_of_le (by positivity : (0 : ℝ) ≤ 1 / 2)] at hx
apply ContinuousAt.cpow
· exact (continuous_const.sub continuous_ofReal).continuousAt
· exact continuousAt_const
· norm_cast
exact ofReal_mem_slitPlane.2 <| by linarith only [hx.2]
#align complex.beta_integral_convergent_left Complex.betaIntegral_convergent_left
theorem betaIntegral_convergent {u v : ℂ} (hu : 0 < re u) (hv : 0 < re v) :
IntervalIntegrable (fun x =>
(x : ℂ) ^ (u - 1) * (1 - (x : ℂ)) ^ (v - 1) : ℝ → ℂ) volume 0 1 := by
refine (betaIntegral_convergent_left hu v).trans ?_
rw [IntervalIntegrable.iff_comp_neg]
convert ((betaIntegral_convergent_left hv u).comp_add_right 1).symm using 1
· ext1 x
conv_lhs => rw [mul_comm]
congr 2 <;> · push_cast; ring
· norm_num
· norm_num
#align complex.beta_integral_convergent Complex.betaIntegral_convergent
theorem betaIntegral_symm (u v : ℂ) : betaIntegral v u = betaIntegral u v := by
rw [betaIntegral, betaIntegral]
have := intervalIntegral.integral_comp_mul_add (a := 0) (b := 1) (c := -1)
(fun x : ℝ => (x : ℂ) ^ (u - 1) * (1 - (x : ℂ)) ^ (v - 1)) neg_one_lt_zero.ne 1
rw [inv_neg, inv_one, neg_one_smul, ← intervalIntegral.integral_symm] at this
simp? at this says
simp only [neg_mul, one_mul, ofReal_add, ofReal_neg, ofReal_one, sub_add_cancel_right, neg_neg,
mul_one, add_left_neg, mul_zero, zero_add] at this
conv_lhs at this => arg 1; intro x; rw [add_comm, ← sub_eq_add_neg, mul_comm]
exact this
#align complex.beta_integral_symm Complex.betaIntegral_symm
theorem betaIntegral_eval_one_right {u : ℂ} (hu : 0 < re u) : betaIntegral u 1 = 1 / u := by
simp_rw [betaIntegral, sub_self, cpow_zero, mul_one]
rw [integral_cpow (Or.inl _)]
· rw [ofReal_zero, ofReal_one, one_cpow, zero_cpow, sub_zero, sub_add_cancel]
rw [sub_add_cancel]
contrapose! hu; rw [hu, zero_re]
· rwa [sub_re, one_re, ← sub_pos, sub_neg_eq_add, sub_add_cancel]
#align complex.beta_integral_eval_one_right Complex.betaIntegral_eval_one_right
theorem betaIntegral_scaled (s t : ℂ) {a : ℝ} (ha : 0 < a) :
∫ x in (0)..a, (x : ℂ) ^ (s - 1) * ((a : ℂ) - x) ^ (t - 1) =
(a : ℂ) ^ (s + t - 1) * betaIntegral s t := by
have ha' : (a : ℂ) ≠ 0 := ofReal_ne_zero.mpr ha.ne'
rw [betaIntegral]
have A : (a : ℂ) ^ (s + t - 1) = a * ((a : ℂ) ^ (s - 1) * (a : ℂ) ^ (t - 1)) := by
rw [(by abel : s + t - 1 = 1 + (s - 1) + (t - 1)), cpow_add _ _ ha', cpow_add 1 _ ha', cpow_one,
mul_assoc]
rw [A, mul_assoc, ← intervalIntegral.integral_const_mul, ← real_smul, ← zero_div a, ←
div_self ha.ne', ← intervalIntegral.integral_comp_div _ ha.ne', zero_div]
simp_rw [intervalIntegral.integral_of_le ha.le]
refine setIntegral_congr measurableSet_Ioc fun x hx => ?_
rw [mul_mul_mul_comm]
congr 1
· rw [← mul_cpow_ofReal_nonneg ha.le (div_pos hx.1 ha).le, ofReal_div, mul_div_cancel₀ _ ha']
· rw [(by norm_cast : (1 : ℂ) - ↑(x / a) = ↑(1 - x / a)), ←
mul_cpow_ofReal_nonneg ha.le (sub_nonneg.mpr <| (div_le_one ha).mpr hx.2)]
push_cast
rw [mul_sub, mul_one, mul_div_cancel₀ _ ha']
#align complex.beta_integral_scaled Complex.betaIntegral_scaled
| Mathlib/Analysis/SpecialFunctions/Gamma/Beta.lean | 136 | 151 | theorem Gamma_mul_Gamma_eq_betaIntegral {s t : ℂ} (hs : 0 < re s) (ht : 0 < re t) :
Gamma s * Gamma t = Gamma (s + t) * betaIntegral s t := by |
-- Note that we haven't proved (yet) that the Gamma function has no zeroes, so we can't formulate
-- this as a formula for the Beta function.
have conv_int := integral_posConvolution
(GammaIntegral_convergent hs) (GammaIntegral_convergent ht) (ContinuousLinearMap.mul ℝ ℂ)
simp_rw [ContinuousLinearMap.mul_apply'] at conv_int
have hst : 0 < re (s + t) := by rw [add_re]; exact add_pos hs ht
rw [Gamma_eq_integral hs, Gamma_eq_integral ht, Gamma_eq_integral hst, GammaIntegral,
GammaIntegral, GammaIntegral, ← conv_int, ← integral_mul_right (betaIntegral _ _)]
refine setIntegral_congr measurableSet_Ioi fun x hx => ?_
rw [mul_assoc, ← betaIntegral_scaled s t hx, ← intervalIntegral.integral_const_mul]
congr 1 with y : 1
push_cast
suffices Complex.exp (-x) = Complex.exp (-y) * Complex.exp (-(x - y)) by rw [this]; ring
rw [← Complex.exp_add]; congr 1; abel
| 0 |
import Mathlib.Data.Complex.Basic
import Mathlib.MeasureTheory.Integral.CircleIntegral
#align_import measure_theory.integral.circle_transform from "leanprover-community/mathlib"@"d11893b411025250c8e61ff2f12ccbd7ee35ab15"
open Set MeasureTheory Metric Filter Function
open scoped Interval Real
noncomputable section
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℂ E] (R : ℝ) (z w : ℂ)
namespace Complex
def circleTransform (f : ℂ → E) (θ : ℝ) : E :=
(2 * ↑π * I)⁻¹ • deriv (circleMap z R) θ • (circleMap z R θ - w)⁻¹ • f (circleMap z R θ)
#align complex.circle_transform Complex.circleTransform
def circleTransformDeriv (f : ℂ → E) (θ : ℝ) : E :=
(2 * ↑π * I)⁻¹ • deriv (circleMap z R) θ • ((circleMap z R θ - w) ^ 2)⁻¹ • f (circleMap z R θ)
#align complex.circle_transform_deriv Complex.circleTransformDeriv
theorem circleTransformDeriv_periodic (f : ℂ → E) :
Periodic (circleTransformDeriv R z w f) (2 * π) := by
have := periodic_circleMap
simp_rw [Periodic] at *
intro x
simp_rw [circleTransformDeriv, this]
congr 2
simp [this]
#align complex.circle_transform_deriv_periodic Complex.circleTransformDeriv_periodic
theorem circleTransformDeriv_eq (f : ℂ → E) : circleTransformDeriv R z w f =
fun θ => (circleMap z R θ - w)⁻¹ • circleTransform R z w f θ := by
ext
simp_rw [circleTransformDeriv, circleTransform, ← mul_smul, ← mul_assoc]
ring_nf
rw [inv_pow]
congr
ring
#align complex.circle_transform_deriv_eq Complex.circleTransformDeriv_eq
theorem integral_circleTransform (f : ℂ → E) :
(∫ θ : ℝ in (0)..2 * π, circleTransform R z w f θ) =
(2 * ↑π * I)⁻¹ • ∮ z in C(z, R), (z - w)⁻¹ • f z := by
simp_rw [circleTransform, circleIntegral, deriv_circleMap, circleMap]
simp
#align complex.integral_circle_transform Complex.integral_circleTransform
| Mathlib/MeasureTheory/Integral/CircleTransform.lean | 75 | 83 | theorem continuous_circleTransform {R : ℝ} (hR : 0 < R) {f : ℂ → E} {z w : ℂ}
(hf : ContinuousOn f <| sphere z R) (hw : w ∈ ball z R) :
Continuous (circleTransform R z w f) := by |
apply_rules [Continuous.smul, continuous_const]
· simp_rw [deriv_circleMap]
apply_rules [Continuous.mul, continuous_circleMap 0 R, continuous_const]
· exact continuous_circleMap_inv hw
· apply ContinuousOn.comp_continuous hf (continuous_circleMap z R)
exact fun _ => (circleMap_mem_sphere _ hR.le) _
| 0 |
import Mathlib.Analysis.Calculus.SmoothSeries
import Mathlib.Analysis.Calculus.BumpFunction.InnerProduct
import Mathlib.Analysis.Convolution
import Mathlib.Analysis.InnerProductSpace.EuclideanDist
import Mathlib.Data.Set.Pointwise.Support
import Mathlib.MeasureTheory.Measure.Haar.NormedSpace
import Mathlib.MeasureTheory.Measure.Haar.Unique
#align_import analysis.calculus.bump_function_findim from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844"
noncomputable section
open Set Metric TopologicalSpace Function Asymptotics MeasureTheory FiniteDimensional
ContinuousLinearMap Filter MeasureTheory.Measure Bornology
open scoped Pointwise Topology NNReal Convolution
variable {E : Type*} [NormedAddCommGroup E]
section
variable [NormedSpace ℝ E] [FiniteDimensional ℝ E]
theorem exists_smooth_tsupport_subset {s : Set E} {x : E} (hs : s ∈ 𝓝 x) :
∃ f : E → ℝ,
tsupport f ⊆ s ∧ HasCompactSupport f ∧ ContDiff ℝ ⊤ f ∧ range f ⊆ Icc 0 1 ∧ f x = 1 := by
obtain ⟨d : ℝ, d_pos : 0 < d, hd : Euclidean.closedBall x d ⊆ s⟩ :=
Euclidean.nhds_basis_closedBall.mem_iff.1 hs
let c : ContDiffBump (toEuclidean x) :=
{ rIn := d / 2
rOut := d
rIn_pos := half_pos d_pos
rIn_lt_rOut := half_lt_self d_pos }
let f : E → ℝ := c ∘ toEuclidean
have f_supp : f.support ⊆ Euclidean.ball x d := by
intro y hy
have : toEuclidean y ∈ Function.support c := by
simpa only [Function.mem_support, Function.comp_apply, Ne] using hy
rwa [c.support_eq] at this
have f_tsupp : tsupport f ⊆ Euclidean.closedBall x d := by
rw [tsupport, ← Euclidean.closure_ball _ d_pos.ne']
exact closure_mono f_supp
refine ⟨f, f_tsupp.trans hd, ?_, ?_, ?_, ?_⟩
· refine isCompact_of_isClosed_isBounded isClosed_closure ?_
have : IsBounded (Euclidean.closedBall x d) := Euclidean.isCompact_closedBall.isBounded
refine this.subset (Euclidean.isClosed_closedBall.closure_subset_iff.2 ?_)
exact f_supp.trans Euclidean.ball_subset_closedBall
· apply c.contDiff.comp
exact ContinuousLinearEquiv.contDiff _
· rintro t ⟨y, rfl⟩
exact ⟨c.nonneg, c.le_one⟩
· apply c.one_of_mem_closedBall
apply mem_closedBall_self
exact (half_pos d_pos).le
#align exists_smooth_tsupport_subset exists_smooth_tsupport_subset
| Mathlib/Analysis/Calculus/BumpFunction/FiniteDimension.lean | 78 | 192 | theorem IsOpen.exists_smooth_support_eq {s : Set E} (hs : IsOpen s) :
∃ f : E → ℝ, f.support = s ∧ ContDiff ℝ ⊤ f ∧ Set.range f ⊆ Set.Icc 0 1 := by |
/- For any given point `x` in `s`, one can construct a smooth function with support in `s` and
nonzero at `x`. By second-countability, it follows that we may cover `s` with the supports of
countably many such functions, say `g i`.
Then `∑ i, r i • g i` will be the desired function if `r i` is a sequence of positive numbers
tending quickly enough to zero. Indeed, this ensures that, for any `k ≤ i`, the `k`-th
derivative of `r i • g i` is bounded by a prescribed (summable) sequence `u i`. From this, the
summability of the series and of its successive derivatives follows. -/
rcases eq_empty_or_nonempty s with (rfl | h's)
· exact
⟨fun _ => 0, Function.support_zero, contDiff_const, by
simp only [range_const, singleton_subset_iff, left_mem_Icc, zero_le_one]⟩
let ι := { f : E → ℝ // f.support ⊆ s ∧ HasCompactSupport f ∧ ContDiff ℝ ⊤ f ∧ range f ⊆ Icc 0 1 }
obtain ⟨T, T_count, hT⟩ : ∃ T : Set ι, T.Countable ∧ ⋃ f ∈ T, support (f : E → ℝ) = s := by
have : ⋃ f : ι, (f : E → ℝ).support = s := by
refine Subset.antisymm (iUnion_subset fun f => f.2.1) ?_
intro x hx
rcases exists_smooth_tsupport_subset (hs.mem_nhds hx) with ⟨f, hf⟩
let g : ι := ⟨f, (subset_tsupport f).trans hf.1, hf.2.1, hf.2.2.1, hf.2.2.2.1⟩
have : x ∈ support (g : E → ℝ) := by
simp only [hf.2.2.2.2, Subtype.coe_mk, mem_support, Ne, one_ne_zero, not_false_iff]
exact mem_iUnion_of_mem _ this
simp_rw [← this]
apply isOpen_iUnion_countable
rintro ⟨f, hf⟩
exact hf.2.2.1.continuous.isOpen_support
obtain ⟨g0, hg⟩ : ∃ g0 : ℕ → ι, T = range g0 := by
apply Countable.exists_eq_range T_count
rcases eq_empty_or_nonempty T with (rfl | hT)
· simp only [ι, iUnion_false, iUnion_empty] at hT
simp only [← hT, mem_empty_iff_false, iUnion_of_empty, iUnion_empty, Set.not_nonempty_empty]
at h's
· exact hT
let g : ℕ → E → ℝ := fun n => (g0 n).1
have g_s : ∀ n, support (g n) ⊆ s := fun n => (g0 n).2.1
have s_g : ∀ x ∈ s, ∃ n, x ∈ support (g n) := fun x hx ↦ by
rw [← hT] at hx
obtain ⟨i, iT, hi⟩ : ∃ i ∈ T, x ∈ support (i : E → ℝ) := by
simpa only [mem_iUnion, exists_prop] using hx
rw [hg, mem_range] at iT
rcases iT with ⟨n, hn⟩
rw [← hn] at hi
exact ⟨n, hi⟩
have g_smooth : ∀ n, ContDiff ℝ ⊤ (g n) := fun n => (g0 n).2.2.2.1
have g_comp_supp : ∀ n, HasCompactSupport (g n) := fun n => (g0 n).2.2.1
have g_nonneg : ∀ n x, 0 ≤ g n x := fun n x => ((g0 n).2.2.2.2 (mem_range_self x)).1
obtain ⟨δ, δpos, c, δc, c_lt⟩ :
∃ δ : ℕ → ℝ≥0, (∀ i : ℕ, 0 < δ i) ∧ ∃ c : NNReal, HasSum δ c ∧ c < 1 :=
NNReal.exists_pos_sum_of_countable one_ne_zero ℕ
have : ∀ n : ℕ, ∃ r : ℝ, 0 < r ∧ ∀ i ≤ n, ∀ x, ‖iteratedFDeriv ℝ i (r • g n) x‖ ≤ δ n := by
intro n
have : ∀ i, ∃ R, ∀ x, ‖iteratedFDeriv ℝ i (fun x => g n x) x‖ ≤ R := by
intro i
have : BddAbove (range fun x => ‖iteratedFDeriv ℝ i (fun x : E => g n x) x‖) := by
apply
((g_smooth n).continuous_iteratedFDeriv le_top).norm.bddAbove_range_of_hasCompactSupport
apply HasCompactSupport.comp_left _ norm_zero
apply (g_comp_supp n).iteratedFDeriv
rcases this with ⟨R, hR⟩
exact ⟨R, fun x => hR (mem_range_self _)⟩
choose R hR using this
let M := max (((Finset.range (n + 1)).image R).max' (by simp)) 1
have δnpos : 0 < δ n := δpos n
have IR : ∀ i ≤ n, R i ≤ M := by
intro i hi
refine le_trans ?_ (le_max_left _ _)
apply Finset.le_max'
apply Finset.mem_image_of_mem
-- Porting note: was
-- simp only [Finset.mem_range]
-- linarith
simpa only [Finset.mem_range, Nat.lt_add_one_iff]
refine ⟨M⁻¹ * δ n, by positivity, fun i hi x => ?_⟩
calc
‖iteratedFDeriv ℝ i ((M⁻¹ * δ n) • g n) x‖ = ‖(M⁻¹ * δ n) • iteratedFDeriv ℝ i (g n) x‖ := by
rw [iteratedFDeriv_const_smul_apply]; exact (g_smooth n).of_le le_top
_ = M⁻¹ * δ n * ‖iteratedFDeriv ℝ i (g n) x‖ := by
rw [norm_smul _ (iteratedFDeriv ℝ i (g n) x), Real.norm_of_nonneg]; positivity
_ ≤ M⁻¹ * δ n * M := (mul_le_mul_of_nonneg_left ((hR i x).trans (IR i hi)) (by positivity))
_ = δ n := by field_simp
choose r rpos hr using this
have S : ∀ x, Summable fun n => (r n • g n) x := fun x ↦ by
refine .of_nnnorm_bounded _ δc.summable fun n => ?_
rw [← NNReal.coe_le_coe, coe_nnnorm]
simpa only [norm_iteratedFDeriv_zero] using hr n 0 (zero_le n) x
refine ⟨fun x => ∑' n, (r n • g n) x, ?_, ?_, ?_⟩
· apply Subset.antisymm
· intro x hx
simp only [Pi.smul_apply, Algebra.id.smul_eq_mul, mem_support, Ne] at hx
contrapose! hx
have : ∀ n, g n x = 0 := by
intro n
contrapose! hx
exact g_s n hx
simp only [this, mul_zero, tsum_zero]
· intro x hx
obtain ⟨n, hn⟩ : ∃ n, x ∈ support (g n) := s_g x hx
have I : 0 < r n * g n x := mul_pos (rpos n) (lt_of_le_of_ne (g_nonneg n x) (Ne.symm hn))
exact ne_of_gt (tsum_pos (S x) (fun i => mul_nonneg (rpos i).le (g_nonneg i x)) n I)
· refine
contDiff_tsum_of_eventually (fun n => (g_smooth n).const_smul (r n))
(fun k _ => (NNReal.hasSum_coe.2 δc).summable) ?_
intro i _
simp only [Nat.cofinite_eq_atTop, Pi.smul_apply, Algebra.id.smul_eq_mul,
Filter.eventually_atTop, ge_iff_le]
exact ⟨i, fun n hn x => hr _ _ hn _⟩
· rintro - ⟨y, rfl⟩
refine ⟨tsum_nonneg fun n => mul_nonneg (rpos n).le (g_nonneg n y), le_trans ?_ c_lt.le⟩
have A : HasSum (fun n => (δ n : ℝ)) c := NNReal.hasSum_coe.2 δc
simp only [Pi.smul_apply, smul_eq_mul, NNReal.val_eq_coe, ← A.tsum_eq, ge_iff_le]
apply tsum_le_tsum _ (S y) A.summable
intro n
apply (le_abs_self _).trans
simpa only [norm_iteratedFDeriv_zero] using hr n 0 (zero_le n) y
| 0 |
import Mathlib.FieldTheory.PrimitiveElement
import Mathlib.LinearAlgebra.Determinant
import Mathlib.LinearAlgebra.FiniteDimensional
import Mathlib.LinearAlgebra.Matrix.Charpoly.Minpoly
import Mathlib.LinearAlgebra.Matrix.ToLinearEquiv
import Mathlib.FieldTheory.IsAlgClosed.AlgebraicClosure
import Mathlib.FieldTheory.Galois
#align_import ring_theory.norm from "leanprover-community/mathlib"@"fecd3520d2a236856f254f27714b80dcfe28ea57"
universe u v w
variable {R S T : Type*} [CommRing R] [Ring S]
variable [Algebra R S]
variable {K L F : Type*} [Field K] [Field L] [Field F]
variable [Algebra K L] [Algebra K F]
variable {ι : Type w}
open FiniteDimensional
open LinearMap
open Matrix Polynomial
open scoped Matrix
namespace Algebra
variable (R)
noncomputable def norm : S →* R :=
LinearMap.det.comp (lmul R S).toRingHom.toMonoidHom
#align algebra.norm Algebra.norm
theorem norm_apply (x : S) : norm R x = LinearMap.det (lmul R S x) := rfl
#align algebra.norm_apply Algebra.norm_apply
theorem norm_eq_one_of_not_exists_basis (h : ¬∃ s : Finset S, Nonempty (Basis s R S)) (x : S) :
norm R x = 1 := by rw [norm_apply, LinearMap.det]; split_ifs <;> trivial
#align algebra.norm_eq_one_of_not_exists_basis Algebra.norm_eq_one_of_not_exists_basis
variable {R}
theorem norm_eq_one_of_not_module_finite (h : ¬Module.Finite R S) (x : S) : norm R x = 1 := by
refine norm_eq_one_of_not_exists_basis _ (mt ?_ h) _
rintro ⟨s, ⟨b⟩⟩
exact Module.Finite.of_basis b
#align algebra.norm_eq_one_of_not_module_finite Algebra.norm_eq_one_of_not_module_finite
-- Can't be a `simp` lemma because it depends on a choice of basis
theorem norm_eq_matrix_det [Fintype ι] [DecidableEq ι] (b : Basis ι R S) (s : S) :
norm R s = Matrix.det (Algebra.leftMulMatrix b s) := by
rw [norm_apply, ← LinearMap.det_toMatrix b, ← toMatrix_lmul_eq]; rfl
#align algebra.norm_eq_matrix_det Algebra.norm_eq_matrix_det
theorem norm_algebraMap_of_basis [Fintype ι] (b : Basis ι R S) (x : R) :
norm R (algebraMap R S x) = x ^ Fintype.card ι := by
haveI := Classical.decEq ι
rw [norm_apply, ← det_toMatrix b, lmul_algebraMap]
convert @det_diagonal _ _ _ _ _ fun _ : ι => x
· ext (i j); rw [toMatrix_lsmul]
· rw [Finset.prod_const, Finset.card_univ]
#align algebra.norm_algebra_map_of_basis Algebra.norm_algebraMap_of_basis
@[simp]
protected theorem norm_algebraMap {L : Type*} [Ring L] [Algebra K L] (x : K) :
norm K (algebraMap K L x) = x ^ finrank K L := by
by_cases H : ∃ s : Finset L, Nonempty (Basis s K L)
· rw [norm_algebraMap_of_basis H.choose_spec.some, finrank_eq_card_basis H.choose_spec.some]
· rw [norm_eq_one_of_not_exists_basis K H, finrank_eq_zero_of_not_exists_basis, pow_zero]
rintro ⟨s, ⟨b⟩⟩
exact H ⟨s, ⟨b⟩⟩
#align algebra.norm_algebra_map Algebra.norm_algebraMap
section EqZeroIff
variable [Finite ι]
@[simp]
| Mathlib/RingTheory/Norm.lean | 145 | 147 | theorem norm_zero [Nontrivial S] [Module.Free R S] [Module.Finite R S] : norm R (0 : S) = 0 := by |
nontriviality
rw [norm_apply, coe_lmul_eq_mul, map_zero, LinearMap.det_zero' (Module.Free.chooseBasis R S)]
| 0 |
import Mathlib.CategoryTheory.Comma.Basic
#align_import category_theory.arrow from "leanprover-community/mathlib"@"32253a1a1071173b33dc7d6a218cf722c6feb514"
namespace CategoryTheory
universe v u
-- morphism levels before object levels. See note [CategoryTheory universes].
variable {T : Type u} [Category.{v} T]
section
variable (T)
def Arrow :=
Comma.{v, v, v} (𝟭 T) (𝟭 T)
#align category_theory.arrow CategoryTheory.Arrow
instance : Category (Arrow T) := commaCategory
-- Satisfying the inhabited linter
instance Arrow.inhabited [Inhabited T] : Inhabited (Arrow T) where
default := show Comma (𝟭 T) (𝟭 T) from default
#align category_theory.arrow.inhabited CategoryTheory.Arrow.inhabited
end
namespace Arrow
@[ext]
lemma hom_ext {X Y : Arrow T} (f g : X ⟶ Y) (h₁ : f.left = g.left) (h₂ : f.right = g.right) :
f = g :=
CommaMorphism.ext _ _ h₁ h₂
@[simp]
theorem id_left (f : Arrow T) : CommaMorphism.left (𝟙 f) = 𝟙 f.left :=
rfl
#align category_theory.arrow.id_left CategoryTheory.Arrow.id_left
@[simp]
theorem id_right (f : Arrow T) : CommaMorphism.right (𝟙 f) = 𝟙 f.right :=
rfl
#align category_theory.arrow.id_right CategoryTheory.Arrow.id_right
-- Porting note (#10688): added to ease automation
@[simp, reassoc]
theorem comp_left {X Y Z : Arrow T} (f : X ⟶ Y) (g : Y ⟶ Z) :
(f ≫ g).left = f.left ≫ g.left := rfl
-- Porting note (#10688): added to ease automation
@[simp, reassoc]
theorem comp_right {X Y Z : Arrow T} (f : X ⟶ Y) (g : Y ⟶ Z) :
(f ≫ g).right = f.right ≫ g.right := rfl
@[simps]
def mk {X Y : T} (f : X ⟶ Y) : Arrow T where
left := X
right := Y
hom := f
#align category_theory.arrow.mk CategoryTheory.Arrow.mk
@[simp]
theorem mk_eq (f : Arrow T) : Arrow.mk f.hom = f := by
cases f
rfl
#align category_theory.arrow.mk_eq CategoryTheory.Arrow.mk_eq
theorem mk_injective (A B : T) :
Function.Injective (Arrow.mk : (A ⟶ B) → Arrow T) := fun f g h => by
cases h
rfl
#align category_theory.arrow.mk_injective CategoryTheory.Arrow.mk_injective
theorem mk_inj (A B : T) {f g : A ⟶ B} : Arrow.mk f = Arrow.mk g ↔ f = g :=
(mk_injective A B).eq_iff
#align category_theory.arrow.mk_inj CategoryTheory.Arrow.mk_inj
instance {X Y : T} : CoeOut (X ⟶ Y) (Arrow T) where
coe := mk
@[simps]
def homMk {f g : Arrow T} {u : f.left ⟶ g.left} {v : f.right ⟶ g.right}
(w : u ≫ g.hom = f.hom ≫ v) : f ⟶ g where
left := u
right := v
w := w
#align category_theory.arrow.hom_mk CategoryTheory.Arrow.homMk
@[simps]
def homMk' {X Y : T} {f : X ⟶ Y} {P Q : T} {g : P ⟶ Q} {u : X ⟶ P} {v : Y ⟶ Q} (w : u ≫ g = f ≫ v) :
Arrow.mk f ⟶ Arrow.mk g where
left := u
right := v
w := w
#align category_theory.arrow.hom_mk' CategoryTheory.Arrow.homMk'
@[reassoc (attr := simp, nolint simpNF)]
theorem w {f g : Arrow T} (sq : f ⟶ g) : sq.left ≫ g.hom = f.hom ≫ sq.right :=
sq.w
#align category_theory.arrow.w CategoryTheory.Arrow.w
-- `w_mk_left` is not needed, as it is a consequence of `w` and `mk_hom`.
@[reassoc (attr := simp)]
theorem w_mk_right {f : Arrow T} {X Y : T} {g : X ⟶ Y} (sq : f ⟶ mk g) :
sq.left ≫ g = f.hom ≫ sq.right :=
sq.w
#align category_theory.arrow.w_mk_right CategoryTheory.Arrow.w_mk_right
| Mathlib/CategoryTheory/Comma/Arrow.lean | 138 | 143 | theorem isIso_of_isIso_left_of_isIso_right {f g : Arrow T} (ff : f ⟶ g) [IsIso ff.left]
[IsIso ff.right] : IsIso ff where
out := by |
let inverse : g ⟶ f := ⟨inv ff.left, inv ff.right, (by simp)⟩
apply Exists.intro inverse
aesop_cat
| 0 |
import Mathlib.MeasureTheory.Function.SimpleFuncDenseLp
#align_import measure_theory.integral.set_to_l1 from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
noncomputable section
open scoped Classical Topology NNReal ENNReal MeasureTheory Pointwise
open Set Filter TopologicalSpace ENNReal EMetric
namespace MeasureTheory
variable {α E F F' G 𝕜 : Type*} {p : ℝ≥0∞} [NormedAddCommGroup E] [NormedSpace ℝ E]
[NormedAddCommGroup F] [NormedSpace ℝ F] [NormedAddCommGroup F'] [NormedSpace ℝ F']
[NormedAddCommGroup G] {m : MeasurableSpace α} {μ : Measure α}
local infixr:25 " →ₛ " => SimpleFunc
open Finset
section FinMeasAdditive
def FinMeasAdditive {β} [AddMonoid β] {_ : MeasurableSpace α} (μ : Measure α) (T : Set α → β) :
Prop :=
∀ s t, MeasurableSet s → MeasurableSet t → μ s ≠ ∞ → μ t ≠ ∞ → s ∩ t = ∅ → T (s ∪ t) = T s + T t
#align measure_theory.fin_meas_additive MeasureTheory.FinMeasAdditive
namespace FinMeasAdditive
variable {β : Type*} [AddCommMonoid β] {T T' : Set α → β}
theorem zero : FinMeasAdditive μ (0 : Set α → β) := fun s t _ _ _ _ _ => by simp
#align measure_theory.fin_meas_additive.zero MeasureTheory.FinMeasAdditive.zero
theorem add (hT : FinMeasAdditive μ T) (hT' : FinMeasAdditive μ T') :
FinMeasAdditive μ (T + T') := by
intro s t hs ht hμs hμt hst
simp only [hT s t hs ht hμs hμt hst, hT' s t hs ht hμs hμt hst, Pi.add_apply]
abel
#align measure_theory.fin_meas_additive.add MeasureTheory.FinMeasAdditive.add
theorem smul [Monoid 𝕜] [DistribMulAction 𝕜 β] (hT : FinMeasAdditive μ T) (c : 𝕜) :
FinMeasAdditive μ fun s => c • T s := fun s t hs ht hμs hμt hst => by
simp [hT s t hs ht hμs hμt hst]
#align measure_theory.fin_meas_additive.smul MeasureTheory.FinMeasAdditive.smul
theorem of_eq_top_imp_eq_top {μ' : Measure α} (h : ∀ s, MeasurableSet s → μ s = ∞ → μ' s = ∞)
(hT : FinMeasAdditive μ T) : FinMeasAdditive μ' T := fun s t hs ht hμ's hμ't hst =>
hT s t hs ht (mt (h s hs) hμ's) (mt (h t ht) hμ't) hst
#align measure_theory.fin_meas_additive.of_eq_top_imp_eq_top MeasureTheory.FinMeasAdditive.of_eq_top_imp_eq_top
theorem of_smul_measure (c : ℝ≥0∞) (hc_ne_top : c ≠ ∞) (hT : FinMeasAdditive (c • μ) T) :
FinMeasAdditive μ T := by
refine of_eq_top_imp_eq_top (fun s _ hμs => ?_) hT
rw [Measure.smul_apply, smul_eq_mul, ENNReal.mul_eq_top] at hμs
simp only [hc_ne_top, or_false_iff, Ne, false_and_iff] at hμs
exact hμs.2
#align measure_theory.fin_meas_additive.of_smul_measure MeasureTheory.FinMeasAdditive.of_smul_measure
theorem smul_measure (c : ℝ≥0∞) (hc_ne_zero : c ≠ 0) (hT : FinMeasAdditive μ T) :
FinMeasAdditive (c • μ) T := by
refine of_eq_top_imp_eq_top (fun s _ hμs => ?_) hT
rw [Measure.smul_apply, smul_eq_mul, ENNReal.mul_eq_top]
simp only [hc_ne_zero, true_and_iff, Ne, not_false_iff]
exact Or.inl hμs
#align measure_theory.fin_meas_additive.smul_measure MeasureTheory.FinMeasAdditive.smul_measure
theorem smul_measure_iff (c : ℝ≥0∞) (hc_ne_zero : c ≠ 0) (hc_ne_top : c ≠ ∞) :
FinMeasAdditive (c • μ) T ↔ FinMeasAdditive μ T :=
⟨fun hT => of_smul_measure c hc_ne_top hT, fun hT => smul_measure c hc_ne_zero hT⟩
#align measure_theory.fin_meas_additive.smul_measure_iff MeasureTheory.FinMeasAdditive.smul_measure_iff
| Mathlib/MeasureTheory/Integral/SetToL1.lean | 143 | 149 | theorem map_empty_eq_zero {β} [AddCancelMonoid β] {T : Set α → β} (hT : FinMeasAdditive μ T) :
T ∅ = 0 := by |
have h_empty : μ ∅ ≠ ∞ := (measure_empty.le.trans_lt ENNReal.coe_lt_top).ne
specialize hT ∅ ∅ MeasurableSet.empty MeasurableSet.empty h_empty h_empty (Set.inter_empty ∅)
rw [Set.union_empty] at hT
nth_rw 1 [← add_zero (T ∅)] at hT
exact (add_left_cancel hT).symm
| 0 |
import Mathlib.Data.Finset.Fold
import Mathlib.Algebra.GCDMonoid.Multiset
#align_import algebra.gcd_monoid.finset from "leanprover-community/mathlib"@"9003f28797c0664a49e4179487267c494477d853"
#align_import algebra.gcd_monoid.div from "leanprover-community/mathlib"@"b537794f8409bc9598febb79cd510b1df5f4539d"
variable {ι α β γ : Type*}
namespace Finset
open Multiset
variable [CancelCommMonoidWithZero α] [NormalizedGCDMonoid α]
section gcd
def gcd (s : Finset β) (f : β → α) : α :=
s.fold GCDMonoid.gcd 0 f
#align finset.gcd Finset.gcd
variable {s s₁ s₂ : Finset β} {f : β → α}
theorem gcd_def : s.gcd f = (s.1.map f).gcd :=
rfl
#align finset.gcd_def Finset.gcd_def
@[simp]
theorem gcd_empty : (∅ : Finset β).gcd f = 0 :=
fold_empty
#align finset.gcd_empty Finset.gcd_empty
theorem dvd_gcd_iff {a : α} : a ∣ s.gcd f ↔ ∀ b ∈ s, a ∣ f b := by
apply Iff.trans Multiset.dvd_gcd
simp only [Multiset.mem_map, and_imp, exists_imp]
exact ⟨fun k b hb ↦ k _ _ hb rfl, fun k a' b hb h ↦ h ▸ k _ hb⟩
#align finset.dvd_gcd_iff Finset.dvd_gcd_iff
theorem gcd_dvd {b : β} (hb : b ∈ s) : s.gcd f ∣ f b :=
dvd_gcd_iff.1 dvd_rfl _ hb
#align finset.gcd_dvd Finset.gcd_dvd
theorem dvd_gcd {a : α} : (∀ b ∈ s, a ∣ f b) → a ∣ s.gcd f :=
dvd_gcd_iff.2
#align finset.dvd_gcd Finset.dvd_gcd
@[simp]
theorem gcd_insert [DecidableEq β] {b : β} :
(insert b s : Finset β).gcd f = GCDMonoid.gcd (f b) (s.gcd f) := by
by_cases h : b ∈ s
· rw [insert_eq_of_mem h,
(gcd_eq_right_iff (f b) (s.gcd f) (Multiset.normalize_gcd (s.1.map f))).2 (gcd_dvd h)]
apply fold_insert h
#align finset.gcd_insert Finset.gcd_insert
@[simp]
theorem gcd_singleton {b : β} : ({b} : Finset β).gcd f = normalize (f b) :=
Multiset.gcd_singleton
#align finset.gcd_singleton Finset.gcd_singleton
-- Porting note: Priority changed for `simpNF`
@[simp 1100]
theorem normalize_gcd : normalize (s.gcd f) = s.gcd f := by simp [gcd_def]
#align finset.normalize_gcd Finset.normalize_gcd
theorem gcd_union [DecidableEq β] : (s₁ ∪ s₂).gcd f = GCDMonoid.gcd (s₁.gcd f) (s₂.gcd f) :=
Finset.induction_on s₁ (by rw [empty_union, gcd_empty, gcd_zero_left, normalize_gcd])
fun a s _ ih ↦ by rw [insert_union, gcd_insert, gcd_insert, ih, gcd_assoc]
#align finset.gcd_union Finset.gcd_union
theorem gcd_congr {f g : β → α} (hs : s₁ = s₂) (hfg : ∀ a ∈ s₂, f a = g a) :
s₁.gcd f = s₂.gcd g := by
subst hs
exact Finset.fold_congr hfg
#align finset.gcd_congr Finset.gcd_congr
theorem gcd_mono_fun {g : β → α} (h : ∀ b ∈ s, f b ∣ g b) : s.gcd f ∣ s.gcd g :=
dvd_gcd fun b hb ↦ (gcd_dvd hb).trans (h b hb)
#align finset.gcd_mono_fun Finset.gcd_mono_fun
theorem gcd_mono (h : s₁ ⊆ s₂) : s₂.gcd f ∣ s₁.gcd f :=
dvd_gcd fun _ hb ↦ gcd_dvd (h hb)
#align finset.gcd_mono Finset.gcd_mono
theorem gcd_image [DecidableEq β] {g : γ → β} (s : Finset γ) :
(s.image g).gcd f = s.gcd (f ∘ g) := by
classical induction' s using Finset.induction with c s _ ih <;> simp [*]
#align finset.gcd_image Finset.gcd_image
theorem gcd_eq_gcd_image [DecidableEq α] : s.gcd f = (s.image f).gcd id :=
Eq.symm <| gcd_image _
#align finset.gcd_eq_gcd_image Finset.gcd_eq_gcd_image
theorem gcd_eq_zero_iff : s.gcd f = 0 ↔ ∀ x : β, x ∈ s → f x = 0 := by
rw [gcd_def, Multiset.gcd_eq_zero_iff]
constructor <;> intro h
· intro b bs
apply h (f b)
simp only [Multiset.mem_map, mem_def.1 bs]
use b
simp only [mem_def.1 bs, eq_self_iff_true, and_self]
· intro a as
rw [Multiset.mem_map] at as
rcases as with ⟨b, ⟨bs, rfl⟩⟩
apply h b (mem_def.1 bs)
#align finset.gcd_eq_zero_iff Finset.gcd_eq_zero_iff
| Mathlib/Algebra/GCDMonoid/Finset.lean | 228 | 241 | theorem gcd_eq_gcd_filter_ne_zero [DecidablePred fun x : β ↦ f x = 0] :
s.gcd f = (s.filter fun x ↦ f x ≠ 0).gcd f := by |
classical
trans ((s.filter fun x ↦ f x = 0) ∪ s.filter fun x ↦ (f x ≠ 0)).gcd f
· rw [filter_union_filter_neg_eq]
rw [gcd_union]
refine Eq.trans (?_ : _ = GCDMonoid.gcd (0 : α) ?_) (?_ : GCDMonoid.gcd (0 : α) _ = _)
· exact (gcd (filter (fun x => (f x ≠ 0)) s) f)
· refine congr (congr rfl <| s.induction_on ?_ ?_) (by simp)
· simp
· intro a s _ h
rw [filter_insert]
split_ifs with h1 <;> simp [h, h1]
simp only [gcd_zero_left, normalize_gcd]
| 0 |
import Mathlib.Analysis.InnerProductSpace.Orthogonal
import Mathlib.Analysis.Normed.Group.AddTorsor
#align_import geometry.euclidean.basic from "leanprover-community/mathlib"@"2de9c37fa71dde2f1c6feff19876dd6a7b1519f0"
open Set
open scoped RealInnerProductSpace
variable {V P : Type*} [NormedAddCommGroup V] [InnerProductSpace ℝ V] [MetricSpace P]
variable [NormedAddTorsor V P]
noncomputable section
namespace AffineSubspace
variable {c c₁ c₂ p₁ p₂ : P}
def perpBisector (p₁ p₂ : P) : AffineSubspace ℝ P :=
.comap ((AffineEquiv.vaddConst ℝ (midpoint ℝ p₁ p₂)).symm : P →ᵃ[ℝ] V) <|
(LinearMap.ker (innerₛₗ ℝ (p₂ -ᵥ p₁))).toAffineSubspace
theorem mem_perpBisector_iff_inner_eq_zero' :
c ∈ perpBisector p₁ p₂ ↔ ⟪p₂ -ᵥ p₁, c -ᵥ midpoint ℝ p₁ p₂⟫ = 0 :=
Iff.rfl
theorem mem_perpBisector_iff_inner_eq_zero :
c ∈ perpBisector p₁ p₂ ↔ ⟪c -ᵥ midpoint ℝ p₁ p₂, p₂ -ᵥ p₁⟫ = 0 :=
inner_eq_zero_symm
theorem mem_perpBisector_iff_inner_pointReflection_vsub_eq_zero :
c ∈ perpBisector p₁ p₂ ↔ ⟪Equiv.pointReflection c p₁ -ᵥ p₂, p₂ -ᵥ p₁⟫ = 0 := by
rw [mem_perpBisector_iff_inner_eq_zero, Equiv.pointReflection_apply,
vsub_midpoint, invOf_eq_inv, ← smul_add, real_inner_smul_left, vadd_vsub_assoc]
simp
theorem mem_perpBisector_pointReflection_iff_inner_eq_zero :
c ∈ perpBisector p₁ (Equiv.pointReflection p₂ p₁) ↔ ⟪c -ᵥ p₂, p₁ -ᵥ p₂⟫ = 0 := by
rw [mem_perpBisector_iff_inner_eq_zero, midpoint_pointReflection_right,
Equiv.pointReflection_apply, vadd_vsub_assoc, inner_add_right, add_self_eq_zero,
← neg_eq_zero, ← inner_neg_right, neg_vsub_eq_vsub_rev]
theorem midpoint_mem_perpBisector (p₁ p₂ : P) :
midpoint ℝ p₁ p₂ ∈ perpBisector p₁ p₂ := by
simp [mem_perpBisector_iff_inner_eq_zero]
theorem perpBisector_nonempty : (perpBisector p₁ p₂ : Set P).Nonempty :=
⟨_, midpoint_mem_perpBisector _ _⟩
@[simp]
| Mathlib/Geometry/Euclidean/PerpBisector.lean | 73 | 78 | theorem direction_perpBisector (p₁ p₂ : P) :
(perpBisector p₁ p₂).direction = (ℝ ∙ (p₂ -ᵥ p₁))ᗮ := by |
erw [perpBisector, comap_symm, map_direction, Submodule.map_id,
Submodule.toAffineSubspace_direction]
ext x
exact Submodule.mem_orthogonal_singleton_iff_inner_right.symm
| 0 |
import Mathlib.RingTheory.Ideal.QuotientOperations
import Mathlib.RingTheory.Localization.Basic
#align_import ring_theory.localization.ideal from "leanprover-community/mathlib"@"e7f0ddbf65bd7181a85edb74b64bdc35ba4bdc74"
namespace IsLocalization
section CommSemiring
variable {R : Type*} [CommSemiring R] (M : Submonoid R) (S : Type*) [CommSemiring S]
variable [Algebra R S] [IsLocalization M S]
private def map_ideal (I : Ideal R) : Ideal S where
carrier := { z : S | ∃ x : I × M, z * algebraMap R S x.2 = algebraMap R S x.1 }
zero_mem' := ⟨⟨0, 1⟩, by simp⟩
add_mem' := by
rintro a b ⟨a', ha⟩ ⟨b', hb⟩
let Z : { x // x ∈ I } := ⟨(a'.2 : R) * (b'.1 : R) + (b'.2 : R) * (a'.1 : R),
I.add_mem (I.mul_mem_left _ b'.1.2) (I.mul_mem_left _ a'.1.2)⟩
use ⟨Z, a'.2 * b'.2⟩
simp only [RingHom.map_add, Submodule.coe_mk, Submonoid.coe_mul, RingHom.map_mul]
rw [add_mul, ← mul_assoc a, ha, mul_comm (algebraMap R S a'.2) (algebraMap R S b'.2), ←
mul_assoc b, hb]
ring
smul_mem' := by
rintro c x ⟨x', hx⟩
obtain ⟨c', hc⟩ := IsLocalization.surj M c
let Z : { x // x ∈ I } := ⟨c'.1 * x'.1, I.mul_mem_left c'.1 x'.1.2⟩
use ⟨Z, c'.2 * x'.2⟩
simp only [← hx, ← hc, smul_eq_mul, Submodule.coe_mk, Submonoid.coe_mul, RingHom.map_mul]
ring
-- Porting note: removed #align declaration since it is a private def
theorem mem_map_algebraMap_iff {I : Ideal R} {z} : z ∈ Ideal.map (algebraMap R S) I ↔
∃ x : I × M, z * algebraMap R S x.2 = algebraMap R S x.1 := by
constructor
· change _ → z ∈ map_ideal M S I
refine fun h => Ideal.mem_sInf.1 h fun z hz => ?_
obtain ⟨y, hy⟩ := hz
let Z : { x // x ∈ I } := ⟨y, hy.left⟩
use ⟨Z, 1⟩
simp [hy.right]
· rintro ⟨⟨a, s⟩, h⟩
rw [← Ideal.unit_mul_mem_iff_mem _ (map_units S s), mul_comm]
exact h.symm ▸ Ideal.mem_map_of_mem _ a.2
#align is_localization.mem_map_algebra_map_iff IsLocalization.mem_map_algebraMap_iff
theorem map_comap (J : Ideal S) : Ideal.map (algebraMap R S) (Ideal.comap (algebraMap R S) J) = J :=
le_antisymm (Ideal.map_le_iff_le_comap.2 le_rfl) fun x hJ => by
obtain ⟨r, s, hx⟩ := mk'_surjective M x
rw [← hx] at hJ ⊢
exact
Ideal.mul_mem_right _ _
(Ideal.mem_map_of_mem _
(show (algebraMap R S) r ∈ J from
mk'_spec S r s ▸ J.mul_mem_right ((algebraMap R S) s) hJ))
#align is_localization.map_comap IsLocalization.map_comap
| Mathlib/RingTheory/Localization/Ideal.lean | 78 | 89 | theorem comap_map_of_isPrime_disjoint (I : Ideal R) (hI : I.IsPrime) (hM : Disjoint (M : Set R) I) :
Ideal.comap (algebraMap R S) (Ideal.map (algebraMap R S) I) = I := by |
refine le_antisymm ?_ Ideal.le_comap_map
refine (fun a ha => ?_)
obtain ⟨⟨b, s⟩, h⟩ := (mem_map_algebraMap_iff M S).1 (Ideal.mem_comap.1 ha)
replace h : algebraMap R S (s * a) = algebraMap R S b := by
simpa only [← map_mul, mul_comm] using h
obtain ⟨c, hc⟩ := (eq_iff_exists M S).1 h
have : ↑c * ↑s * a ∈ I := by
rw [mul_assoc, hc]
exact I.mul_mem_left c b.2
exact (hI.mem_or_mem this).resolve_left fun hsc => hM.le_bot ⟨(c * s).2, hsc⟩
| 0 |
import Mathlib.Algebra.GCDMonoid.Finset
import Mathlib.Algebra.Polynomial.CancelLeads
import Mathlib.Algebra.Polynomial.EraseLead
import Mathlib.Algebra.Polynomial.FieldDivision
#align_import ring_theory.polynomial.content from "leanprover-community/mathlib"@"7a030ab8eb5d99f05a891dccc49c5b5b90c947d3"
namespace Polynomial
open Polynomial
variable {R : Type*} [CommRing R] [IsDomain R]
section NormalizedGCDMonoid
variable [NormalizedGCDMonoid R]
def content (p : R[X]) : R :=
p.support.gcd p.coeff
#align polynomial.content Polynomial.content
theorem content_dvd_coeff {p : R[X]} (n : ℕ) : p.content ∣ p.coeff n := by
by_cases h : n ∈ p.support
· apply Finset.gcd_dvd h
rw [mem_support_iff, Classical.not_not] at h
rw [h]
apply dvd_zero
#align polynomial.content_dvd_coeff Polynomial.content_dvd_coeff
@[simp]
theorem content_C {r : R} : (C r).content = normalize r := by
rw [content]
by_cases h0 : r = 0
· simp [h0]
have h : (C r).support = {0} := support_monomial _ h0
simp [h]
set_option linter.uppercaseLean3 false in
#align polynomial.content_C Polynomial.content_C
@[simp]
theorem content_zero : content (0 : R[X]) = 0 := by rw [← C_0, content_C, normalize_zero]
#align polynomial.content_zero Polynomial.content_zero
@[simp]
theorem content_one : content (1 : R[X]) = 1 := by rw [← C_1, content_C, normalize_one]
#align polynomial.content_one Polynomial.content_one
theorem content_X_mul {p : R[X]} : content (X * p) = content p := by
rw [content, content, Finset.gcd_def, Finset.gcd_def]
refine congr rfl ?_
have h : (X * p).support = p.support.map ⟨Nat.succ, Nat.succ_injective⟩ := by
ext a
simp only [exists_prop, Finset.mem_map, Function.Embedding.coeFn_mk, Ne, mem_support_iff]
cases' a with a
· simp [coeff_X_mul_zero, Nat.succ_ne_zero]
rw [mul_comm, coeff_mul_X]
constructor
· intro h
use a
· rintro ⟨b, ⟨h1, h2⟩⟩
rw [← Nat.succ_injective h2]
apply h1
rw [h]
simp only [Finset.map_val, Function.comp_apply, Function.Embedding.coeFn_mk, Multiset.map_map]
refine congr (congr rfl ?_) rfl
ext a
rw [mul_comm]
simp [coeff_mul_X]
set_option linter.uppercaseLean3 false in
#align polynomial.content_X_mul Polynomial.content_X_mul
@[simp]
| Mathlib/RingTheory/Polynomial/Content.lean | 134 | 137 | theorem content_X_pow {k : ℕ} : content ((X : R[X]) ^ k) = 1 := by |
induction' k with k hi
· simp
rw [pow_succ', content_X_mul, hi]
| 0 |
import Batteries.Classes.SatisfiesM
namespace Array
theorem SatisfiesM_foldlM [Monad m] [LawfulMonad m]
{as : Array α} (motive : Nat → β → Prop) {init : β} (h0 : motive 0 init) {f : β → α → m β}
(hf : ∀ i : Fin as.size, ∀ b, motive i.1 b → SatisfiesM (motive (i.1 + 1)) (f b as[i])) :
SatisfiesM (motive as.size) (as.foldlM f init) := by
let rec go {i j b} (h₁ : j ≤ as.size) (h₂ : as.size ≤ i + j) (H : motive j b) :
SatisfiesM (motive as.size) (foldlM.loop f as as.size (Nat.le_refl _) i j b) := by
unfold foldlM.loop; split
· next hj =>
split
· cases Nat.not_le_of_gt (by simp [hj]) h₂
· exact (hf ⟨j, hj⟩ b H).bind fun _ => go hj (by rwa [Nat.succ_add] at h₂)
· next hj => exact Nat.le_antisymm h₁ (Nat.ge_of_not_lt hj) ▸ .pure H
simp [foldlM]; exact go (Nat.zero_le _) (Nat.le_refl _) h0
| .lake/packages/batteries/Batteries/Data/Array/Monadic.lean | 32 | 48 | theorem SatisfiesM_mapM [Monad m] [LawfulMonad m] (as : Array α) (f : α → m β)
(motive : Nat → Prop) (h0 : motive 0)
(p : Fin as.size → β → Prop)
(hs : ∀ i, motive i.1 → SatisfiesM (p i · ∧ motive (i + 1)) (f as[i])) :
SatisfiesM
(fun arr => motive as.size ∧ ∃ eq : arr.size = as.size, ∀ i h, p ⟨i, h⟩ arr[i])
(Array.mapM f as) := by |
rw [mapM_eq_foldlM]
refine SatisfiesM_foldlM (m := m) (β := Array β)
(motive := fun i arr => motive i ∧ arr.size = i ∧ ∀ i h2, p i (arr[i.1]'h2)) ?z ?s
|>.imp fun ⟨h₁, eq, h₂⟩ => ⟨h₁, eq, fun _ _ => h₂ ..⟩
· case z => exact ⟨h0, rfl, nofun⟩
· case s =>
intro ⟨i, hi⟩ arr ⟨ih₁, eq, ih₂⟩
refine (hs _ ih₁).map fun ⟨h₁, h₂⟩ => ⟨h₂, by simp [eq], fun j hj => ?_⟩
simp [get_push] at hj ⊢; split; {apply ih₂}
cases j; cases (Nat.le_or_eq_of_le_succ hj).resolve_left ‹_›; cases eq; exact h₁
| 0 |
import Mathlib.Algebra.NeZero
import Mathlib.Algebra.Polynomial.BigOperators
import Mathlib.Algebra.Polynomial.Lifts
import Mathlib.Algebra.Polynomial.Splits
import Mathlib.RingTheory.RootsOfUnity.Complex
import Mathlib.NumberTheory.ArithmeticFunction
import Mathlib.RingTheory.RootsOfUnity.Basic
import Mathlib.FieldTheory.RatFunc.AsPolynomial
#align_import ring_theory.polynomial.cyclotomic.basic from "leanprover-community/mathlib"@"7fdeecc0d03cd40f7a165e6cf00a4d2286db599f"
open scoped Polynomial
noncomputable section
universe u
namespace Polynomial
section Cyclotomic'
section IsDomain
variable {R : Type*} [CommRing R] [IsDomain R]
def cyclotomic' (n : ℕ) (R : Type*) [CommRing R] [IsDomain R] : R[X] :=
∏ μ ∈ primitiveRoots n R, (X - C μ)
#align polynomial.cyclotomic' Polynomial.cyclotomic'
@[simp]
theorem cyclotomic'_zero (R : Type*) [CommRing R] [IsDomain R] : cyclotomic' 0 R = 1 := by
simp only [cyclotomic', Finset.prod_empty, primitiveRoots_zero]
#align polynomial.cyclotomic'_zero Polynomial.cyclotomic'_zero
@[simp]
theorem cyclotomic'_one (R : Type*) [CommRing R] [IsDomain R] : cyclotomic' 1 R = X - 1 := by
simp only [cyclotomic', Finset.prod_singleton, RingHom.map_one,
IsPrimitiveRoot.primitiveRoots_one]
#align polynomial.cyclotomic'_one Polynomial.cyclotomic'_one
@[simp]
theorem cyclotomic'_two (R : Type*) [CommRing R] [IsDomain R] (p : ℕ) [CharP R p] (hp : p ≠ 2) :
cyclotomic' 2 R = X + 1 := by
rw [cyclotomic']
have prim_root_two : primitiveRoots 2 R = {(-1 : R)} := by
simp only [Finset.eq_singleton_iff_unique_mem, mem_primitiveRoots two_pos]
exact ⟨IsPrimitiveRoot.neg_one p hp, fun x => IsPrimitiveRoot.eq_neg_one_of_two_right⟩
simp only [prim_root_two, Finset.prod_singleton, RingHom.map_neg, RingHom.map_one, sub_neg_eq_add]
#align polynomial.cyclotomic'_two Polynomial.cyclotomic'_two
theorem cyclotomic'.monic (n : ℕ) (R : Type*) [CommRing R] [IsDomain R] :
(cyclotomic' n R).Monic :=
monic_prod_of_monic _ _ fun _ _ => monic_X_sub_C _
#align polynomial.cyclotomic'.monic Polynomial.cyclotomic'.monic
theorem cyclotomic'_ne_zero (n : ℕ) (R : Type*) [CommRing R] [IsDomain R] : cyclotomic' n R ≠ 0 :=
(cyclotomic'.monic n R).ne_zero
#align polynomial.cyclotomic'_ne_zero Polynomial.cyclotomic'_ne_zero
theorem natDegree_cyclotomic' {ζ : R} {n : ℕ} (h : IsPrimitiveRoot ζ n) :
(cyclotomic' n R).natDegree = Nat.totient n := by
rw [cyclotomic']
rw [natDegree_prod (primitiveRoots n R) fun z : R => X - C z]
· simp only [IsPrimitiveRoot.card_primitiveRoots h, mul_one, natDegree_X_sub_C, Nat.cast_id,
Finset.sum_const, nsmul_eq_mul]
intro z _
exact X_sub_C_ne_zero z
#align polynomial.nat_degree_cyclotomic' Polynomial.natDegree_cyclotomic'
theorem degree_cyclotomic' {ζ : R} {n : ℕ} (h : IsPrimitiveRoot ζ n) :
(cyclotomic' n R).degree = Nat.totient n := by
simp only [degree_eq_natDegree (cyclotomic'_ne_zero n R), natDegree_cyclotomic' h]
#align polynomial.degree_cyclotomic' Polynomial.degree_cyclotomic'
theorem roots_of_cyclotomic (n : ℕ) (R : Type*) [CommRing R] [IsDomain R] :
(cyclotomic' n R).roots = (primitiveRoots n R).val := by
rw [cyclotomic']; exact roots_prod_X_sub_C (primitiveRoots n R)
#align polynomial.roots_of_cyclotomic Polynomial.roots_of_cyclotomic
| Mathlib/RingTheory/Polynomial/Cyclotomic/Basic.lean | 131 | 141 | theorem X_pow_sub_one_eq_prod {ζ : R} {n : ℕ} (hpos : 0 < n) (h : IsPrimitiveRoot ζ n) :
X ^ n - 1 = ∏ ζ ∈ nthRootsFinset n R, (X - C ζ) := by |
classical
rw [nthRootsFinset, ← Multiset.toFinset_eq (IsPrimitiveRoot.nthRoots_one_nodup h)]
simp only [Finset.prod_mk, RingHom.map_one]
rw [nthRoots]
have hmonic : (X ^ n - C (1 : R)).Monic := monic_X_pow_sub_C (1 : R) (ne_of_lt hpos).symm
symm
apply prod_multiset_X_sub_C_of_monic_of_roots_card_eq hmonic
rw [@natDegree_X_pow_sub_C R _ _ n 1, ← nthRoots]
exact IsPrimitiveRoot.card_nthRoots_one h
| 0 |
import Mathlib.Data.List.Cycle
import Mathlib.GroupTheory.Perm.Cycle.Type
import Mathlib.GroupTheory.Perm.List
#align_import group_theory.perm.cycle.concrete from "leanprover-community/mathlib"@"00638177efd1b2534fc5269363ebf42a7871df9a"
open Equiv Equiv.Perm List
variable {α : Type*}
namespace List
variable [DecidableEq α] {l l' : List α}
theorem formPerm_disjoint_iff (hl : Nodup l) (hl' : Nodup l') (hn : 2 ≤ l.length)
(hn' : 2 ≤ l'.length) : Perm.Disjoint (formPerm l) (formPerm l') ↔ l.Disjoint l' := by
rw [disjoint_iff_eq_or_eq, List.Disjoint]
constructor
· rintro h x hx hx'
specialize h x
rw [formPerm_apply_mem_eq_self_iff _ hl _ hx, formPerm_apply_mem_eq_self_iff _ hl' _ hx'] at h
omega
· intro h x
by_cases hx : x ∈ l
on_goal 1 => by_cases hx' : x ∈ l'
· exact (h hx hx').elim
all_goals have := formPerm_eq_self_of_not_mem _ _ ‹_›; tauto
#align list.form_perm_disjoint_iff List.formPerm_disjoint_iff
| Mathlib/GroupTheory/Perm/Cycle/Concrete.lean | 73 | 86 | theorem isCycle_formPerm (hl : Nodup l) (hn : 2 ≤ l.length) : IsCycle (formPerm l) := by |
cases' l with x l
· set_option tactic.skipAssignedInstances false in norm_num at hn
induction' l with y l generalizing x
· set_option tactic.skipAssignedInstances false in norm_num at hn
· use x
constructor
· rwa [formPerm_apply_mem_ne_self_iff _ hl _ (mem_cons_self _ _)]
· intro w hw
have : w ∈ x::y::l := mem_of_formPerm_ne_self _ _ hw
obtain ⟨k, hk⟩ := get_of_mem this
use k
rw [← hk]
simp only [zpow_natCast, formPerm_pow_apply_head _ _ hl k, Nat.mod_eq_of_lt k.isLt]
| 0 |
import Mathlib.Topology.MetricSpace.HausdorffDistance
import Mathlib.MeasureTheory.Constructions.BorelSpace.Order
#align_import measure_theory.measure.regular from "leanprover-community/mathlib"@"bf6a01357ff5684b1ebcd0f1a13be314fc82c0bf"
open Set Filter ENNReal Topology NNReal TopologicalSpace
namespace MeasureTheory
namespace Measure
def InnerRegularWRT {α} {_ : MeasurableSpace α} (μ : Measure α) (p q : Set α → Prop) :=
∀ ⦃U⦄, q U → ∀ r < μ U, ∃ K, K ⊆ U ∧ p K ∧ r < μ K
#align measure_theory.measure.inner_regular MeasureTheory.Measure.InnerRegularWRT
namespace InnerRegularWRT
variable {α : Type*} {m : MeasurableSpace α} {μ : Measure α} {p q : Set α → Prop} {U : Set α}
{ε : ℝ≥0∞}
theorem measure_eq_iSup (H : InnerRegularWRT μ p q) (hU : q U) :
μ U = ⨆ (K) (_ : K ⊆ U) (_ : p K), μ K := by
refine
le_antisymm (le_of_forall_lt fun r hr => ?_) (iSup₂_le fun K hK => iSup_le fun _ => μ.mono hK)
simpa only [lt_iSup_iff, exists_prop] using H hU r hr
#align measure_theory.measure.inner_regular.measure_eq_supr MeasureTheory.Measure.InnerRegularWRT.measure_eq_iSup
| Mathlib/MeasureTheory/Measure/Regular.lean | 222 | 228 | theorem exists_subset_lt_add (H : InnerRegularWRT μ p q) (h0 : p ∅) (hU : q U) (hμU : μ U ≠ ∞)
(hε : ε ≠ 0) : ∃ K, K ⊆ U ∧ p K ∧ μ U < μ K + ε := by |
rcases eq_or_ne (μ U) 0 with h₀ | h₀
· refine ⟨∅, empty_subset _, h0, ?_⟩
rwa [measure_empty, h₀, zero_add, pos_iff_ne_zero]
· rcases H hU _ (ENNReal.sub_lt_self hμU h₀ hε) with ⟨K, hKU, hKc, hrK⟩
exact ⟨K, hKU, hKc, ENNReal.lt_add_of_sub_lt_right (Or.inl hμU) hrK⟩
| 0 |
import Mathlib.Algebra.Order.Ring.Abs
import Mathlib.Tactic.Ring
#align_import data.nat.hyperoperation from "leanprover-community/mathlib"@"f7fc89d5d5ff1db2d1242c7bb0e9062ce47ef47c"
def hyperoperation : ℕ → ℕ → ℕ → ℕ
| 0, _, k => k + 1
| 1, m, 0 => m
| 2, _, 0 => 0
| _ + 3, _, 0 => 1
| n + 1, m, k + 1 => hyperoperation n m (hyperoperation (n + 1) m k)
#align hyperoperation hyperoperation
-- Basic hyperoperation lemmas
@[simp]
theorem hyperoperation_zero (m : ℕ) : hyperoperation 0 m = Nat.succ :=
funext fun k => by rw [hyperoperation, Nat.succ_eq_add_one]
#align hyperoperation_zero hyperoperation_zero
theorem hyperoperation_ge_three_eq_one (n m : ℕ) : hyperoperation (n + 3) m 0 = 1 := by
rw [hyperoperation]
#align hyperoperation_ge_three_eq_one hyperoperation_ge_three_eq_one
theorem hyperoperation_recursion (n m k : ℕ) :
hyperoperation (n + 1) m (k + 1) = hyperoperation n m (hyperoperation (n + 1) m k) := by
rw [hyperoperation]
#align hyperoperation_recursion hyperoperation_recursion
-- Interesting hyperoperation lemmas
@[simp]
theorem hyperoperation_one : hyperoperation 1 = (· + ·) := by
ext m k
induction' k with bn bih
· rw [Nat.add_zero m, hyperoperation]
· rw [hyperoperation_recursion, bih, hyperoperation_zero]
exact Nat.add_assoc m bn 1
#align hyperoperation_one hyperoperation_one
@[simp]
theorem hyperoperation_two : hyperoperation 2 = (· * ·) := by
ext m k
induction' k with bn bih
· rw [hyperoperation]
exact (Nat.mul_zero m).symm
· rw [hyperoperation_recursion, hyperoperation_one, bih]
-- Porting note: was `ring`
dsimp only
nth_rewrite 1 [← mul_one m]
rw [← mul_add, add_comm]
#align hyperoperation_two hyperoperation_two
@[simp]
theorem hyperoperation_three : hyperoperation 3 = (· ^ ·) := by
ext m k
induction' k with bn bih
· rw [hyperoperation_ge_three_eq_one]
exact (pow_zero m).symm
· rw [hyperoperation_recursion, hyperoperation_two, bih]
exact (pow_succ' m bn).symm
#align hyperoperation_three hyperoperation_three
| Mathlib/Data/Nat/Hyperoperation.lean | 91 | 95 | theorem hyperoperation_ge_two_eq_self (n m : ℕ) : hyperoperation (n + 2) m 1 = m := by |
induction' n with nn nih
· rw [hyperoperation_two]
ring
· rw [hyperoperation_recursion, hyperoperation_ge_three_eq_one, nih]
| 0 |
import Mathlib.Geometry.Euclidean.Angle.Oriented.Affine
import Mathlib.Geometry.Euclidean.Angle.Unoriented.RightAngle
#align_import geometry.euclidean.angle.oriented.right_angle from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5"
noncomputable section
open scoped EuclideanGeometry
open scoped Real
open scoped RealInnerProductSpace
namespace EuclideanGeometry
open FiniteDimensional
variable {V : Type*} {P : Type*} [NormedAddCommGroup V] [InnerProductSpace ℝ V] [MetricSpace P]
[NormedAddTorsor V P] [hd2 : Fact (finrank ℝ V = 2)] [Module.Oriented ℝ V (Fin 2)]
theorem oangle_right_eq_arccos_of_oangle_eq_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = ↑(π / 2)) :
∡ p₂ p₃ p₁ = Real.arccos (dist p₃ p₂ / dist p₁ p₃) := by
have hs : (∡ p₂ p₃ p₁).sign = 1 := by rw [oangle_rotate_sign, h, Real.Angle.sign_coe_pi_div_two]
rw [oangle_eq_angle_of_sign_eq_one hs,
angle_eq_arccos_of_angle_eq_pi_div_two (angle_eq_pi_div_two_of_oangle_eq_pi_div_two h)]
#align euclidean_geometry.oangle_right_eq_arccos_of_oangle_eq_pi_div_two EuclideanGeometry.oangle_right_eq_arccos_of_oangle_eq_pi_div_two
| Mathlib/Geometry/Euclidean/Angle/Oriented/RightAngle.lean | 592 | 597 | theorem oangle_left_eq_arccos_of_oangle_eq_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = ↑(π / 2)) :
∡ p₃ p₁ p₂ = Real.arccos (dist p₁ p₂ / dist p₁ p₃) := by |
have hs : (∡ p₃ p₁ p₂).sign = 1 := by rw [← oangle_rotate_sign, h, Real.Angle.sign_coe_pi_div_two]
rw [oangle_eq_angle_of_sign_eq_one hs, angle_comm,
angle_eq_arccos_of_angle_eq_pi_div_two (angle_rev_eq_pi_div_two_of_oangle_eq_pi_div_two h),
dist_comm p₁ p₃]
| 0 |
import Mathlib.Algebra.Order.Kleene
import Mathlib.Algebra.Ring.Hom.Defs
import Mathlib.Data.List.Join
import Mathlib.Data.Set.Lattice
import Mathlib.Tactic.DeriveFintype
#align_import computability.language from "leanprover-community/mathlib"@"a239cd3e7ac2c7cde36c913808f9d40c411344f6"
open List Set Computability
universe v
variable {α β γ : Type*}
def Language (α) :=
Set (List α)
#align language Language
instance : Membership (List α) (Language α) := ⟨Set.Mem⟩
instance : Singleton (List α) (Language α) := ⟨Set.singleton⟩
instance : Insert (List α) (Language α) := ⟨Set.insert⟩
instance : CompleteAtomicBooleanAlgebra (Language α) := Set.completeAtomicBooleanAlgebra
namespace Language
variable {l m : Language α} {a b x : List α}
-- Porting note: `reducible` attribute cannot be local.
-- attribute [local reducible] Language
instance : Zero (Language α) :=
⟨(∅ : Set _)⟩
instance : One (Language α) :=
⟨{[]}⟩
instance : Inhabited (Language α) := ⟨(∅ : Set _)⟩
instance : Add (Language α) :=
⟨((· ∪ ·) : Set (List α) → Set (List α) → Set (List α))⟩
instance : Mul (Language α) :=
⟨image2 (· ++ ·)⟩
theorem zero_def : (0 : Language α) = (∅ : Set _) :=
rfl
#align language.zero_def Language.zero_def
theorem one_def : (1 : Language α) = ({[]} : Set (List α)) :=
rfl
#align language.one_def Language.one_def
theorem add_def (l m : Language α) : l + m = (l ∪ m : Set (List α)) :=
rfl
#align language.add_def Language.add_def
theorem mul_def (l m : Language α) : l * m = image2 (· ++ ·) l m :=
rfl
#align language.mul_def Language.mul_def
instance : KStar (Language α) := ⟨fun l ↦ {x | ∃ L : List (List α), x = L.join ∧ ∀ y ∈ L, y ∈ l}⟩
lemma kstar_def (l : Language α) : l∗ = {x | ∃ L : List (List α), x = L.join ∧ ∀ y ∈ L, y ∈ l} :=
rfl
#align language.kstar_def Language.kstar_def
-- Porting note: `reducible` attribute cannot be local,
-- so this new theorem is required in place of `Set.ext`.
@[ext]
theorem ext {l m : Language α} (h : ∀ (x : List α), x ∈ l ↔ x ∈ m) : l = m :=
Set.ext h
@[simp]
theorem not_mem_zero (x : List α) : x ∉ (0 : Language α) :=
id
#align language.not_mem_zero Language.not_mem_zero
@[simp]
theorem mem_one (x : List α) : x ∈ (1 : Language α) ↔ x = [] := by rfl
#align language.mem_one Language.mem_one
theorem nil_mem_one : [] ∈ (1 : Language α) :=
Set.mem_singleton _
#align language.nil_mem_one Language.nil_mem_one
theorem mem_add (l m : Language α) (x : List α) : x ∈ l + m ↔ x ∈ l ∨ x ∈ m :=
Iff.rfl
#align language.mem_add Language.mem_add
theorem mem_mul : x ∈ l * m ↔ ∃ a ∈ l, ∃ b ∈ m, a ++ b = x :=
mem_image2
#align language.mem_mul Language.mem_mul
theorem append_mem_mul : a ∈ l → b ∈ m → a ++ b ∈ l * m :=
mem_image2_of_mem
#align language.append_mem_mul Language.append_mem_mul
theorem mem_kstar : x ∈ l∗ ↔ ∃ L : List (List α), x = L.join ∧ ∀ y ∈ L, y ∈ l :=
Iff.rfl
#align language.mem_kstar Language.mem_kstar
theorem join_mem_kstar {L : List (List α)} (h : ∀ y ∈ L, y ∈ l) : L.join ∈ l∗ :=
⟨L, rfl, h⟩
#align language.join_mem_kstar Language.join_mem_kstar
theorem nil_mem_kstar (l : Language α) : [] ∈ l∗ :=
⟨[], rfl, fun _ h ↦ by contradiction⟩
#align language.nil_mem_kstar Language.nil_mem_kstar
instance instSemiring : Semiring (Language α) where
add := (· + ·)
add_assoc := union_assoc
zero := 0
zero_add := empty_union
add_zero := union_empty
add_comm := union_comm
mul := (· * ·)
mul_assoc _ _ _ := image2_assoc append_assoc
zero_mul _ := image2_empty_left
mul_zero _ := image2_empty_right
one := 1
one_mul l := by simp [mul_def, one_def]
mul_one l := by simp [mul_def, one_def]
natCast n := if n = 0 then 0 else 1
natCast_zero := rfl
natCast_succ n := by cases n <;> simp [Nat.cast, add_def, zero_def]
left_distrib _ _ _ := image2_union_right
right_distrib _ _ _ := image2_union_left
nsmul := nsmulRec
@[simp]
theorem add_self (l : Language α) : l + l = l :=
sup_idem _
#align language.add_self Language.add_self
def map (f : α → β) : Language α →+* Language β where
toFun := image (List.map f)
map_zero' := image_empty _
map_one' := image_singleton
map_add' := image_union _
map_mul' _ _ := image_image2_distrib <| map_append _
#align language.map Language.map
@[simp]
theorem map_id (l : Language α) : map id l = l := by simp [map]
#align language.map_id Language.map_id
@[simp]
| Mathlib/Computability/Language.lean | 175 | 176 | theorem map_map (g : β → γ) (f : α → β) (l : Language α) : map g (map f l) = map (g ∘ f) l := by |
simp [map, image_image]
| 0 |
import Mathlib.RingTheory.GradedAlgebra.HomogeneousIdeal
import Mathlib.Topology.Category.TopCat.Basic
import Mathlib.Topology.Sets.Opens
import Mathlib.Data.Set.Subsingleton
#align_import algebraic_geometry.projective_spectrum.topology from "leanprover-community/mathlib"@"d39590fc8728fbf6743249802486f8c91ffe07bc"
noncomputable section
open DirectSum Pointwise SetLike TopCat TopologicalSpace CategoryTheory Opposite
variable {R A : Type*}
variable [CommSemiring R] [CommRing A] [Algebra R A]
variable (𝒜 : ℕ → Submodule R A) [GradedAlgebra 𝒜]
-- porting note (#5171): removed @[nolint has_nonempty_instance]
@[ext]
structure ProjectiveSpectrum where
asHomogeneousIdeal : HomogeneousIdeal 𝒜
isPrime : asHomogeneousIdeal.toIdeal.IsPrime
not_irrelevant_le : ¬HomogeneousIdeal.irrelevant 𝒜 ≤ asHomogeneousIdeal
#align projective_spectrum ProjectiveSpectrum
attribute [instance] ProjectiveSpectrum.isPrime
namespace ProjectiveSpectrum
def zeroLocus (s : Set A) : Set (ProjectiveSpectrum 𝒜) :=
{ x | s ⊆ x.asHomogeneousIdeal }
#align projective_spectrum.zero_locus ProjectiveSpectrum.zeroLocus
@[simp]
theorem mem_zeroLocus (x : ProjectiveSpectrum 𝒜) (s : Set A) :
x ∈ zeroLocus 𝒜 s ↔ s ⊆ x.asHomogeneousIdeal :=
Iff.rfl
#align projective_spectrum.mem_zero_locus ProjectiveSpectrum.mem_zeroLocus
@[simp]
theorem zeroLocus_span (s : Set A) : zeroLocus 𝒜 (Ideal.span s) = zeroLocus 𝒜 s := by
ext x
exact (Submodule.gi _ _).gc s x.asHomogeneousIdeal.toIdeal
#align projective_spectrum.zero_locus_span ProjectiveSpectrum.zeroLocus_span
variable {𝒜}
def vanishingIdeal (t : Set (ProjectiveSpectrum 𝒜)) : HomogeneousIdeal 𝒜 :=
⨅ (x : ProjectiveSpectrum 𝒜) (_ : x ∈ t), x.asHomogeneousIdeal
#align projective_spectrum.vanishing_ideal ProjectiveSpectrum.vanishingIdeal
| Mathlib/AlgebraicGeometry/ProjectiveSpectrum/Topology.lean | 99 | 106 | theorem coe_vanishingIdeal (t : Set (ProjectiveSpectrum 𝒜)) :
(vanishingIdeal t : Set A) =
{ f | ∀ x : ProjectiveSpectrum 𝒜, x ∈ t → f ∈ x.asHomogeneousIdeal } := by |
ext f
rw [vanishingIdeal, SetLike.mem_coe, ← HomogeneousIdeal.mem_iff, HomogeneousIdeal.toIdeal_iInf,
Submodule.mem_iInf]
refine forall_congr' fun x => ?_
rw [HomogeneousIdeal.toIdeal_iInf, Submodule.mem_iInf, HomogeneousIdeal.mem_iff]
| 0 |
import Mathlib.Algebra.Polynomial.Degree.Definitions
import Mathlib.Algebra.Polynomial.Eval
import Mathlib.Algebra.Polynomial.Monic
import Mathlib.Algebra.Polynomial.RingDivision
import Mathlib.Tactic.Abel
#align_import ring_theory.polynomial.pochhammer from "leanprover-community/mathlib"@"53b216bcc1146df1c4a0a86877890ea9f1f01589"
universe u v
open Polynomial
open Polynomial
section Ring
variable (R : Type u) [Ring R]
noncomputable def descPochhammer : ℕ → R[X]
| 0 => 1
| n + 1 => X * (descPochhammer n).comp (X - 1)
@[simp]
theorem descPochhammer_zero : descPochhammer R 0 = 1 :=
rfl
@[simp]
theorem descPochhammer_one : descPochhammer R 1 = X := by simp [descPochhammer]
theorem descPochhammer_succ_left (n : ℕ) :
descPochhammer R (n + 1) = X * (descPochhammer R n).comp (X - 1) := by
rw [descPochhammer]
| Mathlib/RingTheory/Polynomial/Pochhammer.lean | 262 | 269 | theorem monic_descPochhammer (n : ℕ) [Nontrivial R] [NoZeroDivisors R] :
Monic <| descPochhammer R n := by |
induction' n with n hn
· simp
· have h : leadingCoeff (X - 1 : R[X]) = 1 := leadingCoeff_X_sub_C 1
have : natDegree (X - (1 : R[X])) ≠ 0 := ne_zero_of_eq_one <| natDegree_X_sub_C (1 : R)
rw [descPochhammer_succ_left, Monic.def, leadingCoeff_mul, leadingCoeff_comp this, hn, monic_X,
one_mul, one_mul, h, one_pow]
| 0 |
import Mathlib.Order.RelClasses
#align_import data.sigma.lex from "leanprover-community/mathlib"@"41cf0cc2f528dd40a8f2db167ea4fb37b8fde7f3"
namespace Sigma
variable {ι : Type*} {α : ι → Type*} {r r₁ r₂ : ι → ι → Prop} {s s₁ s₂ : ∀ i, α i → α i → Prop}
{a b : Σ i, α i}
inductive Lex (r : ι → ι → Prop) (s : ∀ i, α i → α i → Prop) : ∀ _ _ : Σ i, α i, Prop
| left {i j : ι} (a : α i) (b : α j) : r i j → Lex r s ⟨i, a⟩ ⟨j, b⟩
| right {i : ι} (a b : α i) : s i a b → Lex r s ⟨i, a⟩ ⟨i, b⟩
#align sigma.lex Sigma.Lex
| Mathlib/Data/Sigma/Lex.lean | 45 | 55 | theorem lex_iff : Lex r s a b ↔ r a.1 b.1 ∨ ∃ h : a.1 = b.1, s b.1 (h.rec a.2) b.2 := by |
constructor
· rintro (⟨a, b, hij⟩ | ⟨a, b, hab⟩)
· exact Or.inl hij
· exact Or.inr ⟨rfl, hab⟩
· obtain ⟨i, a⟩ := a
obtain ⟨j, b⟩ := b
dsimp only
rintro (h | ⟨rfl, h⟩)
· exact Lex.left _ _ h
· exact Lex.right _ _ h
| 0 |
import Mathlib.Algebra.Algebra.Unitization
import Mathlib.Analysis.NormedSpace.OperatorNorm.Mul
suppress_compilation
variable (𝕜 A : Type*) [NontriviallyNormedField 𝕜] [NonUnitalNormedRing A]
variable [NormedSpace 𝕜 A] [IsScalarTower 𝕜 A A] [SMulCommClass 𝕜 A A]
open ContinuousLinearMap
namespace Unitization
def splitMul : Unitization 𝕜 A →ₐ[𝕜] 𝕜 × (A →L[𝕜] A) :=
(lift 0).prod (lift <| NonUnitalAlgHom.Lmul 𝕜 A)
variable {𝕜 A}
@[simp]
theorem splitMul_apply (x : Unitization 𝕜 A) :
splitMul 𝕜 A x = (x.fst, algebraMap 𝕜 (A →L[𝕜] A) x.fst + mul 𝕜 A x.snd) :=
show (x.fst + 0, _) = (x.fst, _) by rw [add_zero]; rfl
| Mathlib/Analysis/NormedSpace/Unitization.lean | 89 | 101 | theorem splitMul_injective_of_clm_mul_injective
(h : Function.Injective (mul 𝕜 A)) :
Function.Injective (splitMul 𝕜 A) := by |
rw [injective_iff_map_eq_zero]
intro x hx
induction x
rw [map_add] at hx
simp only [splitMul_apply, fst_inl, snd_inl, map_zero, add_zero, fst_inr, snd_inr,
zero_add, Prod.mk_add_mk, Prod.mk_eq_zero] at hx
obtain ⟨rfl, hx⟩ := hx
simp only [map_zero, zero_add, inl_zero] at hx ⊢
rw [← map_zero (mul 𝕜 A)] at hx
rw [h hx, inr_zero]
| 0 |
import Mathlib.Data.Matrix.Invertible
import Mathlib.LinearAlgebra.Matrix.NonsingularInverse
import Mathlib.LinearAlgebra.Matrix.PosDef
#align_import linear_algebra.matrix.schur_complement from "leanprover-community/mathlib"@"a176cb1219e300e85793d44583dede42377b51af"
variable {l m n α : Type*}
namespace Matrix
open scoped Matrix
section CommRing
variable [Fintype l] [Fintype m] [Fintype n]
variable [DecidableEq l] [DecidableEq m] [DecidableEq n]
variable [CommRing α]
theorem fromBlocks_eq_of_invertible₁₁ (A : Matrix m m α) (B : Matrix m n α) (C : Matrix l m α)
(D : Matrix l n α) [Invertible A] :
fromBlocks A B C D =
fromBlocks 1 0 (C * ⅟ A) 1 * fromBlocks A 0 0 (D - C * ⅟ A * B) *
fromBlocks 1 (⅟ A * B) 0 1 := by
simp only [fromBlocks_multiply, Matrix.mul_zero, Matrix.zero_mul, add_zero, zero_add,
Matrix.one_mul, Matrix.mul_one, invOf_mul_self, Matrix.mul_invOf_self_assoc,
Matrix.mul_invOf_mul_self_cancel, Matrix.mul_assoc, add_sub_cancel]
#align matrix.from_blocks_eq_of_invertible₁₁ Matrix.fromBlocks_eq_of_invertible₁₁
theorem fromBlocks_eq_of_invertible₂₂ (A : Matrix l m α) (B : Matrix l n α) (C : Matrix n m α)
(D : Matrix n n α) [Invertible D] :
fromBlocks A B C D =
fromBlocks 1 (B * ⅟ D) 0 1 * fromBlocks (A - B * ⅟ D * C) 0 0 D *
fromBlocks 1 0 (⅟ D * C) 1 :=
(Matrix.reindex (Equiv.sumComm _ _) (Equiv.sumComm _ _)).injective <| by
simpa [reindex_apply, Equiv.sumComm_symm, ← submatrix_mul_equiv _ _ _ (Equiv.sumComm n m), ←
submatrix_mul_equiv _ _ _ (Equiv.sumComm n l), Equiv.sumComm_apply,
fromBlocks_submatrix_sum_swap_sum_swap] using fromBlocks_eq_of_invertible₁₁ D C B A
#align matrix.from_blocks_eq_of_invertible₂₂ Matrix.fromBlocks_eq_of_invertible₂₂
section Det
theorem det_fromBlocks₁₁ (A : Matrix m m α) (B : Matrix m n α) (C : Matrix n m α)
(D : Matrix n n α) [Invertible A] :
(Matrix.fromBlocks A B C D).det = det A * det (D - C * ⅟ A * B) := by
rw [fromBlocks_eq_of_invertible₁₁ (A := A), det_mul, det_mul, det_fromBlocks_zero₂₁,
det_fromBlocks_zero₂₁, det_fromBlocks_zero₁₂, det_one, det_one, one_mul, one_mul, mul_one]
#align matrix.det_from_blocks₁₁ Matrix.det_fromBlocks₁₁
@[simp]
theorem det_fromBlocks_one₁₁ (B : Matrix m n α) (C : Matrix n m α) (D : Matrix n n α) :
(Matrix.fromBlocks 1 B C D).det = det (D - C * B) := by
haveI : Invertible (1 : Matrix m m α) := invertibleOne
rw [det_fromBlocks₁₁, invOf_one, Matrix.mul_one, det_one, one_mul]
#align matrix.det_from_blocks_one₁₁ Matrix.det_fromBlocks_one₁₁
theorem det_fromBlocks₂₂ (A : Matrix m m α) (B : Matrix m n α) (C : Matrix n m α)
(D : Matrix n n α) [Invertible D] :
(Matrix.fromBlocks A B C D).det = det D * det (A - B * ⅟ D * C) := by
have : fromBlocks A B C D =
(fromBlocks D C B A).submatrix (Equiv.sumComm _ _) (Equiv.sumComm _ _) := by
ext (i j)
cases i <;> cases j <;> rfl
rw [this, det_submatrix_equiv_self, det_fromBlocks₁₁]
#align matrix.det_from_blocks₂₂ Matrix.det_fromBlocks₂₂
@[simp]
theorem det_fromBlocks_one₂₂ (A : Matrix m m α) (B : Matrix m n α) (C : Matrix n m α) :
(Matrix.fromBlocks A B C 1).det = det (A - B * C) := by
haveI : Invertible (1 : Matrix n n α) := invertibleOne
rw [det_fromBlocks₂₂, invOf_one, Matrix.mul_one, det_one, one_mul]
#align matrix.det_from_blocks_one₂₂ Matrix.det_fromBlocks_one₂₂
theorem det_one_add_mul_comm (A : Matrix m n α) (B : Matrix n m α) :
det (1 + A * B) = det (1 + B * A) :=
calc
det (1 + A * B) = det (fromBlocks 1 (-A) B 1) := by
rw [det_fromBlocks_one₂₂, Matrix.neg_mul, sub_neg_eq_add]
_ = det (1 + B * A) := by rw [det_fromBlocks_one₁₁, Matrix.mul_neg, sub_neg_eq_add]
#align matrix.det_one_add_mul_comm Matrix.det_one_add_mul_comm
theorem det_mul_add_one_comm (A : Matrix m n α) (B : Matrix n m α) :
det (A * B + 1) = det (B * A + 1) := by rw [add_comm, det_one_add_mul_comm, add_comm]
#align matrix.det_mul_add_one_comm Matrix.det_mul_add_one_comm
theorem det_one_sub_mul_comm (A : Matrix m n α) (B : Matrix n m α) :
det (1 - A * B) = det (1 - B * A) := by
rw [sub_eq_add_neg, ← Matrix.neg_mul, det_one_add_mul_comm, Matrix.mul_neg, ← sub_eq_add_neg]
#align matrix.det_one_sub_mul_comm Matrix.det_one_sub_mul_comm
| Mathlib/LinearAlgebra/Matrix/SchurComplement.lean | 444 | 446 | theorem det_one_add_col_mul_row (u v : m → α) : det (1 + col u * row v) = 1 + v ⬝ᵥ u := by |
rw [det_one_add_mul_comm, det_unique, Pi.add_apply, Pi.add_apply, Matrix.one_apply_eq,
Matrix.row_mul_col_apply]
| 0 |
import Mathlib.Analysis.NormedSpace.Star.Basic
import Mathlib.Analysis.NormedSpace.Unitization
#align_import analysis.normed_space.star.mul from "leanprover-community/mathlib"@"b2ff9a3d7a15fd5b0f060b135421d6a89a999c2f"
open ContinuousLinearMap
local postfix:max "⋆" => star
variable (𝕜 : Type*) {E : Type*}
variable [DenselyNormedField 𝕜] [NonUnitalNormedRing E] [StarRing E] [CstarRing E]
variable [NormedSpace 𝕜 E] [IsScalarTower 𝕜 E E] [SMulCommClass 𝕜 E E]
variable (E)
instance CstarRing.instRegularNormedAlgebra : RegularNormedAlgebra 𝕜 E where
isometry_mul' := AddMonoidHomClass.isometry_of_norm (mul 𝕜 E) fun a => NNReal.eq_iff.mpr <|
show ‖mul 𝕜 E a‖₊ = ‖a‖₊ by
rw [← sSup_closed_unit_ball_eq_nnnorm]
refine csSup_eq_of_forall_le_of_forall_lt_exists_gt ?_ ?_ fun r hr => ?_
· exact (Metric.nonempty_closedBall.mpr zero_le_one).image _
· rintro - ⟨x, hx, rfl⟩
exact
((mul 𝕜 E a).unit_le_opNorm x <| mem_closedBall_zero_iff.mp hx).trans
(opNorm_mul_apply_le 𝕜 E a)
· have ha : 0 < ‖a‖₊ := zero_le'.trans_lt hr
rw [← inv_inv ‖a‖₊, NNReal.lt_inv_iff_mul_lt (inv_ne_zero ha.ne')] at hr
obtain ⟨k, hk₁, hk₂⟩ :=
NormedField.exists_lt_nnnorm_lt 𝕜 (mul_lt_mul_of_pos_right hr <| inv_pos.2 ha)
refine ⟨_, ⟨k • star a, ?_, rfl⟩, ?_⟩
· simpa only [mem_closedBall_zero_iff, norm_smul, one_mul, norm_star] using
(NNReal.le_inv_iff_mul_le ha.ne').1 (one_mul ‖a‖₊⁻¹ ▸ hk₂.le : ‖k‖₊ ≤ ‖a‖₊⁻¹)
· simp only [map_smul, nnnorm_smul, mul_apply', mul_smul_comm, CstarRing.nnnorm_self_mul_star]
rwa [← NNReal.div_lt_iff (mul_pos ha ha).ne', div_eq_mul_inv, mul_inv, ← mul_assoc]
section CStarProperty
variable [StarRing 𝕜] [CstarRing 𝕜] [StarModule 𝕜 E]
variable {E}
| Mathlib/Analysis/NormedSpace/Star/Unitization.lean | 87 | 124 | theorem Unitization.norm_splitMul_snd_sq (x : Unitization 𝕜 E) :
‖(Unitization.splitMul 𝕜 E x).snd‖ ^ 2 ≤ ‖(Unitization.splitMul 𝕜 E (star x * x)).snd‖ := by |
/- The key idea is that we can use `sSup_closed_unit_ball_eq_norm` to make this about
applying this linear map to elements of norm at most one. There is a bit of `sqrt` and `sq`
shuffling that needs to occur, which is primarily just an annoyance. -/
refine (Real.le_sqrt (norm_nonneg _) (norm_nonneg _)).mp ?_
simp only [Unitization.splitMul_apply]
rw [← sSup_closed_unit_ball_eq_norm]
refine csSup_le ((Metric.nonempty_closedBall.2 zero_le_one).image _) ?_
rintro - ⟨b, hb, rfl⟩
simp only
-- rewrite to a more convenient form; this is where we use the C⋆-property
rw [← Real.sqrt_sq (norm_nonneg _), Real.sqrt_le_sqrt_iff (norm_nonneg _), sq,
← CstarRing.norm_star_mul_self, ContinuousLinearMap.add_apply, star_add, mul_apply',
Algebra.algebraMap_eq_smul_one, ContinuousLinearMap.smul_apply,
ContinuousLinearMap.one_apply, star_mul, star_smul, add_mul, smul_mul_assoc, ← mul_smul_comm,
mul_assoc, ← mul_add, ← sSup_closed_unit_ball_eq_norm]
refine (norm_mul_le _ _).trans ?_
calc
_ ≤ ‖star x.fst • (x.fst • b + x.snd * b) + star x.snd * (x.fst • b + x.snd * b)‖ := by
nth_rewrite 2 [← one_mul ‖_ + _‖]
gcongr
exact (norm_star b).symm ▸ mem_closedBall_zero_iff.1 hb
_ ≤ sSup (_ '' Metric.closedBall 0 1) := le_csSup ?_ ⟨b, hb, ?_⟩
-- now we just check the side conditions for `le_csSup`. There is nothing of interest here.
· refine ⟨‖(star x * x).fst‖ + ‖(star x * x).snd‖, ?_⟩
rintro _ ⟨y, hy, rfl⟩
refine (norm_add_le _ _).trans ?_
gcongr
· rw [Algebra.algebraMap_eq_smul_one]
refine (norm_smul _ _).trans_le ?_
simpa only [mul_one] using
mul_le_mul_of_nonneg_left (mem_closedBall_zero_iff.1 hy) (norm_nonneg (star x * x).fst)
· exact (unit_le_opNorm _ y <| mem_closedBall_zero_iff.1 hy).trans (opNorm_mul_apply_le _ _ _)
· simp only [ContinuousLinearMap.add_apply, mul_apply', Unitization.snd_star, Unitization.snd_mul,
Unitization.fst_mul, Unitization.fst_star, Algebra.algebraMap_eq_smul_one, smul_apply,
one_apply, smul_add, mul_add, add_mul]
simp only [smul_smul, smul_mul_assoc, ← add_assoc, ← mul_assoc, mul_smul_comm]
| 0 |
import Mathlib.Algebra.CharP.Basic
import Mathlib.Algebra.CharP.Algebra
import Mathlib.Data.Nat.Prime
#align_import algebra.char_p.exp_char from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
universe u
variable (R : Type u)
section Semiring
variable [Semiring R]
class inductive ExpChar (R : Type u) [Semiring R] : ℕ → Prop
| zero [CharZero R] : ExpChar R 1
| prime {q : ℕ} (hprime : q.Prime) [hchar : CharP R q] : ExpChar R q
#align exp_char ExpChar
#align exp_char.prime ExpChar.prime
instance expChar_prime (p) [CharP R p] [Fact p.Prime] : ExpChar R p := ExpChar.prime Fact.out
instance expChar_zero [CharZero R] : ExpChar R 1 := ExpChar.zero
instance (S : Type*) [Semiring S] (p) [ExpChar R p] [ExpChar S p] : ExpChar (R × S) p := by
obtain hp | ⟨hp⟩ := ‹ExpChar R p›
· have := Prod.charZero_of_left R S; exact .zero
obtain _ | _ := ‹ExpChar S p›
· exact (Nat.not_prime_one hp).elim
· have := Prod.charP R S p; exact .prime hp
variable {R} in
| Mathlib/Algebra/CharP/ExpChar.lean | 61 | 67 | theorem ExpChar.eq {p q : ℕ} (hp : ExpChar R p) (hq : ExpChar R q) : p = q := by |
cases' hp with hp _ hp' hp
· cases' hq with hq _ hq' hq
exacts [rfl, False.elim (Nat.not_prime_zero (CharP.eq R hq (CharP.ofCharZero R) ▸ hq'))]
· cases' hq with hq _ hq' hq
exacts [False.elim (Nat.not_prime_zero (CharP.eq R hp (CharP.ofCharZero R) ▸ hp')),
CharP.eq R hp hq]
| 0 |
import Mathlib.Algebra.CharP.ExpChar
import Mathlib.RingTheory.Nilpotent.Defs
#align_import algebra.char_p.basic from "leanprover-community/mathlib"@"47a1a73351de8dd6c8d3d32b569c8e434b03ca47"
open Finset
section
variable (R : Type*) [CommRing R] [IsReduced R] (p n : ℕ) [ExpChar R p]
theorem iterateFrobenius_inj : Function.Injective (iterateFrobenius R p n) := fun x y H ↦ by
rw [← sub_eq_zero] at H ⊢
simp_rw [iterateFrobenius_def, ← sub_pow_expChar_pow] at H
exact IsReduced.eq_zero _ ⟨_, H⟩
theorem frobenius_inj : Function.Injective (frobenius R p) :=
iterateFrobenius_one (R := R) p ▸ iterateFrobenius_inj R p 1
#align frobenius_inj frobenius_inj
end
| Mathlib/Algebra/CharP/Reduced.lean | 35 | 40 | theorem isSquare_of_charTwo' {R : Type*} [Finite R] [CommRing R] [IsReduced R] [CharP R 2]
(a : R) : IsSquare a := by |
cases nonempty_fintype R
exact
Exists.imp (fun b h => pow_two b ▸ Eq.symm h)
(((Fintype.bijective_iff_injective_and_card _).mpr ⟨frobenius_inj R 2, rfl⟩).surjective a)
| 0 |
import Mathlib.Analysis.Convex.Combination
import Mathlib.Analysis.Convex.Join
#align_import analysis.convex.stone_separation from "leanprover-community/mathlib"@"6ca1a09bc9aa75824bf97388c9e3b441fc4ccf3f"
open Set
variable {𝕜 E ι : Type*} [LinearOrderedField 𝕜] [AddCommGroup E] [Module 𝕜 E] {s t : Set E}
theorem not_disjoint_segment_convexHull_triple {p q u v x y z : E} (hz : z ∈ segment 𝕜 x y)
(hu : u ∈ segment 𝕜 x p) (hv : v ∈ segment 𝕜 y q) :
¬Disjoint (segment 𝕜 u v) (convexHull 𝕜 {p, q, z}) := by
rw [not_disjoint_iff]
obtain ⟨az, bz, haz, hbz, habz, rfl⟩ := hz
obtain rfl | haz' := haz.eq_or_lt
· rw [zero_add] at habz
rw [zero_smul, zero_add, habz, one_smul]
refine ⟨v, by apply right_mem_segment, segment_subset_convexHull ?_ ?_ hv⟩ <;> simp
obtain ⟨av, bv, hav, hbv, habv, rfl⟩ := hv
obtain rfl | hav' := hav.eq_or_lt
· rw [zero_add] at habv
rw [zero_smul, zero_add, habv, one_smul]
exact ⟨q, right_mem_segment _ _ _, subset_convexHull _ _ <| by simp⟩
obtain ⟨au, bu, hau, hbu, habu, rfl⟩ := hu
have hab : 0 < az * av + bz * au := by positivity
refine ⟨(az * av / (az * av + bz * au)) • (au • x + bu • p) +
(bz * au / (az * av + bz * au)) • (av • y + bv • q), ⟨_, _, ?_, ?_, ?_, rfl⟩, ?_⟩
· positivity
· positivity
· rw [← add_div, div_self]; positivity
rw [smul_add, smul_add, add_add_add_comm, add_comm, ← mul_smul, ← mul_smul]
classical
let w : Fin 3 → 𝕜 := ![az * av * bu, bz * au * bv, au * av]
let z : Fin 3 → E := ![p, q, az • x + bz • y]
have hw₀ : ∀ i, 0 ≤ w i := by
rintro i
fin_cases i
· exact mul_nonneg (mul_nonneg haz hav) hbu
· exact mul_nonneg (mul_nonneg hbz hau) hbv
· exact mul_nonneg hau hav
have hw : ∑ i, w i = az * av + bz * au := by
trans az * av * bu + (bz * au * bv + au * av)
· simp [w, Fin.sum_univ_succ, Fin.sum_univ_zero]
rw [← one_mul (au * av), ← habz, add_mul, ← add_assoc, add_add_add_comm, mul_assoc, ← mul_add,
mul_assoc, ← mul_add, mul_comm av, ← add_mul, ← mul_add, add_comm bu, add_comm bv, habu,
habv, one_mul, mul_one]
have hz : ∀ i, z i ∈ ({p, q, az • x + bz • y} : Set E) := fun i => by fin_cases i <;> simp [z]
convert Finset.centerMass_mem_convexHull (Finset.univ : Finset (Fin 3)) (fun i _ => hw₀ i)
(by rwa [hw]) fun i _ => hz i
rw [Finset.centerMass]
simp_rw [div_eq_inv_mul, hw, mul_assoc, mul_smul (az * av + bz * au)⁻¹, ← smul_add, add_assoc, ←
mul_assoc]
congr 3
rw [← mul_smul, ← mul_rotate, mul_right_comm, mul_smul, ← mul_smul _ av, mul_rotate,
mul_smul _ bz, ← smul_add]
simp only [w, z, smul_add, List.foldr, Matrix.cons_val_succ', Fin.mk_one,
Matrix.cons_val_one, Matrix.head_cons, add_zero]
#align not_disjoint_segment_convex_hull_triple not_disjoint_segment_convexHull_triple
| Mathlib/Analysis/Convex/StoneSeparation.lean | 81 | 109 | theorem exists_convex_convex_compl_subset (hs : Convex 𝕜 s) (ht : Convex 𝕜 t) (hst : Disjoint s t) :
∃ C : Set E, Convex 𝕜 C ∧ Convex 𝕜 Cᶜ ∧ s ⊆ C ∧ t ⊆ Cᶜ := by |
let S : Set (Set E) := { C | Convex 𝕜 C ∧ Disjoint C t }
obtain ⟨C, hC, hsC, hCmax⟩ :=
zorn_subset_nonempty S
(fun c hcS hc ⟨_, _⟩ =>
⟨⋃₀ c,
⟨hc.directedOn.convex_sUnion fun s hs => (hcS hs).1,
disjoint_sUnion_left.2 fun c hc => (hcS hc).2⟩,
fun s => subset_sUnion_of_mem⟩)
s ⟨hs, hst⟩
refine
⟨C, hC.1, convex_iff_segment_subset.2 fun x hx y hy z hz hzC => ?_, hsC, hC.2.subset_compl_left⟩
suffices h : ∀ c ∈ Cᶜ, ∃ a ∈ C, (segment 𝕜 c a ∩ t).Nonempty by
obtain ⟨p, hp, u, hu, hut⟩ := h x hx
obtain ⟨q, hq, v, hv, hvt⟩ := h y hy
refine
not_disjoint_segment_convexHull_triple hz hu hv
(hC.2.symm.mono (ht.segment_subset hut hvt) <| convexHull_min ?_ hC.1)
simp [insert_subset_iff, hp, hq, singleton_subset_iff.2 hzC]
rintro c hc
by_contra! h
suffices h : Disjoint (convexHull 𝕜 (insert c C)) t by
rw [←
hCmax _ ⟨convex_convexHull _ _, h⟩ ((subset_insert _ _).trans <| subset_convexHull _ _)] at hc
exact hc (subset_convexHull _ _ <| mem_insert _ _)
rw [convexHull_insert ⟨z, hzC⟩, convexJoin_singleton_left]
refine disjoint_iUnion₂_left.2 fun a ha => disjoint_iff_inter_eq_empty.2 (h a ?_)
rwa [← hC.1.convexHull_eq]
| 0 |
import Mathlib.Topology.Bases
import Mathlib.Topology.DenseEmbedding
#align_import topology.stone_cech from "leanprover-community/mathlib"@"0a0ec35061ed9960bf0e7ffb0335f44447b58977"
noncomputable section
open Filter Set
open Topology
universe u v
section Ultrafilter
def ultrafilterBasis (α : Type u) : Set (Set (Ultrafilter α)) :=
range fun s : Set α => { u | s ∈ u }
#align ultrafilter_basis ultrafilterBasis
variable {α : Type u}
instance Ultrafilter.topologicalSpace : TopologicalSpace (Ultrafilter α) :=
TopologicalSpace.generateFrom (ultrafilterBasis α)
#align ultrafilter.topological_space Ultrafilter.topologicalSpace
theorem ultrafilterBasis_is_basis : TopologicalSpace.IsTopologicalBasis (ultrafilterBasis α) :=
⟨by
rintro _ ⟨a, rfl⟩ _ ⟨b, rfl⟩ u ⟨ua, ub⟩
refine ⟨_, ⟨a ∩ b, rfl⟩, inter_mem ua ub, fun v hv => ⟨?_, ?_⟩⟩ <;> apply mem_of_superset hv <;>
simp [inter_subset_right],
eq_univ_of_univ_subset <| subset_sUnion_of_mem <| ⟨univ, eq_univ_of_forall fun u => univ_mem⟩,
rfl⟩
#align ultrafilter_basis_is_basis ultrafilterBasis_is_basis
theorem ultrafilter_isOpen_basic (s : Set α) : IsOpen { u : Ultrafilter α | s ∈ u } :=
ultrafilterBasis_is_basis.isOpen ⟨s, rfl⟩
#align ultrafilter_is_open_basic ultrafilter_isOpen_basic
theorem ultrafilter_isClosed_basic (s : Set α) : IsClosed { u : Ultrafilter α | s ∈ u } := by
rw [← isOpen_compl_iff]
convert ultrafilter_isOpen_basic sᶜ using 1
ext u
exact Ultrafilter.compl_mem_iff_not_mem.symm
#align ultrafilter_is_closed_basic ultrafilter_isClosed_basic
theorem ultrafilter_converges_iff {u : Ultrafilter (Ultrafilter α)} {x : Ultrafilter α} :
↑u ≤ 𝓝 x ↔ x = joinM u := by
rw [eq_comm, ← Ultrafilter.coe_le_coe]
change ↑u ≤ 𝓝 x ↔ ∀ s ∈ x, { v : Ultrafilter α | s ∈ v } ∈ u
simp only [TopologicalSpace.nhds_generateFrom, le_iInf_iff, ultrafilterBasis, le_principal_iff,
mem_setOf_eq]
constructor
· intro h a ha
exact h _ ⟨ha, a, rfl⟩
· rintro h a ⟨xi, a, rfl⟩
exact h _ xi
#align ultrafilter_converges_iff ultrafilter_converges_iff
instance ultrafilter_compact : CompactSpace (Ultrafilter α) :=
⟨isCompact_iff_ultrafilter_le_nhds.mpr fun f _ =>
⟨joinM f, trivial, ultrafilter_converges_iff.mpr rfl⟩⟩
#align ultrafilter_compact ultrafilter_compact
instance Ultrafilter.t2Space : T2Space (Ultrafilter α) :=
t2_iff_ultrafilter.mpr @fun x y f fx fy =>
have hx : x = joinM f := ultrafilter_converges_iff.mp fx
have hy : y = joinM f := ultrafilter_converges_iff.mp fy
hx.trans hy.symm
#align ultrafilter.t2_space Ultrafilter.t2Space
instance : TotallyDisconnectedSpace (Ultrafilter α) := by
rw [totallyDisconnectedSpace_iff_connectedComponent_singleton]
intro A
simp only [Set.eq_singleton_iff_unique_mem, mem_connectedComponent, true_and_iff]
intro B hB
rw [← Ultrafilter.coe_le_coe]
intro s hs
rw [connectedComponent_eq_iInter_isClopen, Set.mem_iInter] at hB
let Z := { F : Ultrafilter α | s ∈ F }
have hZ : IsClopen Z := ⟨ultrafilter_isClosed_basic s, ultrafilter_isOpen_basic s⟩
exact hB ⟨Z, hZ, hs⟩
@[simp] theorem Ultrafilter.tendsto_pure_self (b : Ultrafilter α) : Tendsto pure b (𝓝 b) := by
rw [Tendsto, ← coe_map, ultrafilter_converges_iff]
ext s
change s ∈ b ↔ {t | s ∈ t} ∈ map pure b
simp_rw [mem_map, preimage_setOf_eq, mem_pure, setOf_mem_eq]
theorem ultrafilter_comap_pure_nhds (b : Ultrafilter α) : comap pure (𝓝 b) ≤ b := by
rw [TopologicalSpace.nhds_generateFrom]
simp only [comap_iInf, comap_principal]
intro s hs
rw [← le_principal_iff]
refine iInf_le_of_le { u | s ∈ u } ?_
refine iInf_le_of_le ⟨hs, ⟨s, rfl⟩⟩ ?_
exact principal_mono.2 fun a => id
#align ultrafilter_comap_pure_nhds ultrafilter_comap_pure_nhds
section Embedding
theorem ultrafilter_pure_injective : Function.Injective (pure : α → Ultrafilter α) := by
intro x y h
have : {x} ∈ (pure x : Ultrafilter α) := singleton_mem_pure
rw [h] at this
exact (mem_singleton_iff.mp (mem_pure.mp this)).symm
#align ultrafilter_pure_injective ultrafilter_pure_injective
open TopologicalSpace
theorem denseRange_pure : DenseRange (pure : α → Ultrafilter α) := fun x =>
mem_closure_iff_ultrafilter.mpr
⟨x.map pure, range_mem_map, ultrafilter_converges_iff.mpr (bind_pure x).symm⟩
#align dense_range_pure denseRange_pure
| Mathlib/Topology/StoneCech.lean | 138 | 143 | theorem induced_topology_pure :
TopologicalSpace.induced (pure : α → Ultrafilter α) Ultrafilter.topologicalSpace = ⊥ := by |
apply eq_bot_of_singletons_open
intro x
use { u : Ultrafilter α | {x} ∈ u }, ultrafilter_isOpen_basic _
simp
| 0 |
import Mathlib.Probability.ProbabilityMassFunction.Basic
#align_import probability.probability_mass_function.monad from "leanprover-community/mathlib"@"4ac69b290818724c159de091daa3acd31da0ee6d"
noncomputable section
variable {α β γ : Type*}
open scoped Classical
open NNReal ENNReal
open MeasureTheory
namespace PMF
section Pure
def pure (a : α) : PMF α :=
⟨fun a' => if a' = a then 1 else 0, hasSum_ite_eq _ _⟩
#align pmf.pure PMF.pure
variable (a a' : α)
@[simp]
theorem pure_apply : pure a a' = if a' = a then 1 else 0 := rfl
#align pmf.pure_apply PMF.pure_apply
@[simp]
theorem support_pure : (pure a).support = {a} :=
Set.ext fun a' => by simp [mem_support_iff]
#align pmf.support_pure PMF.support_pure
theorem mem_support_pure_iff : a' ∈ (pure a).support ↔ a' = a := by simp
#align pmf.mem_support_pure_iff PMF.mem_support_pure_iff
-- @[simp] -- Porting note (#10618): simp can prove this
theorem pure_apply_self : pure a a = 1 :=
if_pos rfl
#align pmf.pure_apply_self PMF.pure_apply_self
theorem pure_apply_of_ne (h : a' ≠ a) : pure a a' = 0 :=
if_neg h
#align pmf.pure_apply_of_ne PMF.pure_apply_of_ne
instance [Inhabited α] : Inhabited (PMF α) :=
⟨pure default⟩
section Measure
variable (s : Set α)
@[simp]
| Mathlib/Probability/ProbabilityMassFunction/Monad.lean | 74 | 80 | theorem toOuterMeasure_pure_apply : (pure a).toOuterMeasure s = if a ∈ s then 1 else 0 := by |
refine (toOuterMeasure_apply (pure a) s).trans ?_
split_ifs with ha
· refine (tsum_congr fun b => ?_).trans (tsum_ite_eq a 1)
exact ite_eq_left_iff.2 fun hb => symm (ite_eq_right_iff.2 fun h => (hb <| h.symm ▸ ha).elim)
· refine (tsum_congr fun b => ?_).trans tsum_zero
exact ite_eq_right_iff.2 fun hb => ite_eq_right_iff.2 fun h => (ha <| h ▸ hb).elim
| 0 |
import Mathlib.Algebra.Polynomial.UnitTrinomial
import Mathlib.RingTheory.Polynomial.GaussLemma
import Mathlib.Tactic.LinearCombination
#align_import ring_theory.polynomial.selmer from "leanprover-community/mathlib"@"3e00d81bdcbf77c8188bbd18f5524ddc3ed8cac6"
namespace Polynomial
open scoped Polynomial
variable {n : ℕ}
theorem X_pow_sub_X_sub_one_irreducible_aux (z : ℂ) : ¬(z ^ n = z + 1 ∧ z ^ n + z ^ 2 = 0) := by
rintro ⟨h1, h2⟩
replace h3 : z ^ 3 = 1 := by
linear_combination (1 - z - z ^ 2 - z ^ n) * h1 + (z ^ n - 2) * h2
have key : z ^ n = 1 ∨ z ^ n = z ∨ z ^ n = z ^ 2 := by
rw [← Nat.mod_add_div n 3, pow_add, pow_mul, h3, one_pow, mul_one]
have : n % 3 < 3 := Nat.mod_lt n zero_lt_three
interval_cases n % 3 <;>
simp only [this, pow_zero, pow_one, eq_self_iff_true, or_true_iff, true_or_iff]
have z_ne_zero : z ≠ 0 := fun h =>
zero_ne_one ((zero_pow three_ne_zero).symm.trans (show (0 : ℂ) ^ 3 = 1 from h ▸ h3))
rcases key with (key | key | key)
· exact z_ne_zero (by rwa [key, self_eq_add_left] at h1)
· exact one_ne_zero (by rwa [key, self_eq_add_right] at h1)
· exact z_ne_zero (pow_eq_zero (by rwa [key, add_self_eq_zero] at h2))
set_option linter.uppercaseLean3 false in
#align polynomial.X_pow_sub_X_sub_one_irreducible_aux Polynomial.X_pow_sub_X_sub_one_irreducible_aux
theorem X_pow_sub_X_sub_one_irreducible (hn1 : n ≠ 1) : Irreducible (X ^ n - X - 1 : ℤ[X]) := by
by_cases hn0 : n = 0
· rw [hn0, pow_zero, sub_sub, add_comm, ← sub_sub, sub_self, zero_sub]
exact Associated.irreducible ⟨-1, mul_neg_one X⟩ irreducible_X
have hn : 1 < n := Nat.one_lt_iff_ne_zero_and_ne_one.mpr ⟨hn0, hn1⟩
have hp : (X ^ n - X - 1 : ℤ[X]) = trinomial 0 1 n (-1) (-1) 1 := by
simp only [trinomial, C_neg, C_1]; ring
rw [hp]
apply IsUnitTrinomial.irreducible_of_coprime' ⟨0, 1, n, zero_lt_one, hn, -1, -1, 1, rfl⟩
rintro z ⟨h1, h2⟩
apply X_pow_sub_X_sub_one_irreducible_aux (n := n) z
rw [trinomial_mirror zero_lt_one hn (-1 : ℤˣ).ne_zero (1 : ℤˣ).ne_zero] at h2
simp_rw [trinomial, aeval_add, aeval_mul, aeval_X_pow, aeval_C,
Units.val_neg, Units.val_one, map_neg, map_one] at h1 h2
replace h1 : z ^ n = z + 1 := by linear_combination h1
replace h2 := mul_eq_zero_of_left h2 z
rw [add_mul, add_mul, add_zero, mul_assoc (-1 : ℂ), ← pow_succ, Nat.sub_add_cancel hn.le] at h2
rw [h1] at h2 ⊢
exact ⟨rfl, by linear_combination -h2⟩
set_option linter.uppercaseLean3 false in
#align polynomial.X_pow_sub_X_sub_one_irreducible Polynomial.X_pow_sub_X_sub_one_irreducible
| Mathlib/RingTheory/Polynomial/Selmer.lean | 71 | 82 | theorem X_pow_sub_X_sub_one_irreducible_rat (hn1 : n ≠ 1) : Irreducible (X ^ n - X - 1 : ℚ[X]) := by |
by_cases hn0 : n = 0
· rw [hn0, pow_zero, sub_sub, add_comm, ← sub_sub, sub_self, zero_sub]
exact Associated.irreducible ⟨-1, mul_neg_one X⟩ irreducible_X
have hp : (X ^ n - X - 1 : ℤ[X]) = trinomial 0 1 n (-1) (-1) 1 := by
simp only [trinomial, C_neg, C_1]; ring
have hn : 1 < n := Nat.one_lt_iff_ne_zero_and_ne_one.mpr ⟨hn0, hn1⟩
have h := (IsPrimitive.Int.irreducible_iff_irreducible_map_cast ?_).mp
(X_pow_sub_X_sub_one_irreducible hn1)
· rwa [Polynomial.map_sub, Polynomial.map_sub, Polynomial.map_pow, Polynomial.map_one,
Polynomial.map_X] at h
· exact hp.symm ▸ (trinomial_monic zero_lt_one hn).isPrimitive
| 0 |
import Mathlib.CategoryTheory.EqToHom
import Mathlib.CategoryTheory.Quotient
import Mathlib.Combinatorics.Quiver.Path
#align_import category_theory.path_category from "leanprover-community/mathlib"@"c6dd521ebdce53bb372c527569dd7c25de53a08b"
universe v₁ v₂ u₁ u₂
namespace CategoryTheory
section
def Paths (V : Type u₁) : Type u₁ := V
#align category_theory.paths CategoryTheory.Paths
instance (V : Type u₁) [Inhabited V] : Inhabited (Paths V) := ⟨(default : V)⟩
variable (V : Type u₁) [Quiver.{v₁ + 1} V]
namespace Paths
instance categoryPaths : Category.{max u₁ v₁} (Paths V) where
Hom := fun X Y : V => Quiver.Path X Y
id X := Quiver.Path.nil
comp f g := Quiver.Path.comp f g
#align category_theory.paths.category_paths CategoryTheory.Paths.categoryPaths
variable {V}
@[simps]
def of : V ⥤q Paths V where
obj X := X
map f := f.toPath
#align category_theory.paths.of CategoryTheory.Paths.of
attribute [local ext] Functor.ext
def lift {C} [Category C] (φ : V ⥤q C) : Paths V ⥤ C where
obj := φ.obj
map {X} {Y} f :=
@Quiver.Path.rec V _ X (fun Y _ => φ.obj X ⟶ φ.obj Y) (𝟙 <| φ.obj X)
(fun _ f ihp => ihp ≫ φ.map f) Y f
map_id X := rfl
map_comp f g := by
induction' g with _ _ g' p ih _ _ _
· rw [Category.comp_id]
rfl
· have : f ≫ Quiver.Path.cons g' p = (f ≫ g').cons p := by apply Quiver.Path.comp_cons
rw [this]
simp only at ih ⊢
rw [ih, Category.assoc]
#align category_theory.paths.lift CategoryTheory.Paths.lift
@[simp]
theorem lift_nil {C} [Category C] (φ : V ⥤q C) (X : V) :
(lift φ).map Quiver.Path.nil = 𝟙 (φ.obj X) := rfl
#align category_theory.paths.lift_nil CategoryTheory.Paths.lift_nil
@[simp]
theorem lift_cons {C} [Category C] (φ : V ⥤q C) {X Y Z : V} (p : Quiver.Path X Y) (f : Y ⟶ Z) :
(lift φ).map (p.cons f) = (lift φ).map p ≫ φ.map f := rfl
#align category_theory.paths.lift_cons CategoryTheory.Paths.lift_cons
@[simp]
theorem lift_toPath {C} [Category C] (φ : V ⥤q C) {X Y : V} (f : X ⟶ Y) :
(lift φ).map f.toPath = φ.map f := by
dsimp [Quiver.Hom.toPath, lift]
simp
#align category_theory.paths.lift_to_path CategoryTheory.Paths.lift_toPath
theorem lift_spec {C} [Category C] (φ : V ⥤q C) : of ⋙q (lift φ).toPrefunctor = φ := by
fapply Prefunctor.ext
· rintro X
rfl
· rintro X Y f
rcases φ with ⟨φo, φm⟩
dsimp [lift, Quiver.Hom.toPath]
simp only [Category.id_comp]
#align category_theory.paths.lift_spec CategoryTheory.Paths.lift_spec
theorem lift_unique {C} [Category C] (φ : V ⥤q C) (Φ : Paths V ⥤ C)
(hΦ : of ⋙q Φ.toPrefunctor = φ) : Φ = lift φ := by
subst_vars
fapply Functor.ext
· rintro X
rfl
· rintro X Y f
dsimp [lift]
induction' f with _ _ p f' ih
· simp only [Category.comp_id]
apply Functor.map_id
· simp only [Category.comp_id, Category.id_comp] at ih ⊢
-- Porting note: Had to do substitute `p.cons f'` and `f'.toPath` by their fully qualified
-- versions in this `have` clause (elsewhere too).
have : Φ.map (Quiver.Path.cons p f') = Φ.map p ≫ Φ.map (Quiver.Hom.toPath f') := by
convert Functor.map_comp Φ p (Quiver.Hom.toPath f')
rw [this, ih]
#align category_theory.paths.lift_unique CategoryTheory.Paths.lift_unique
@[ext]
| Mathlib/CategoryTheory/PathCategory.lean | 124 | 135 | theorem ext_functor {C} [Category C] {F G : Paths V ⥤ C} (h_obj : F.obj = G.obj)
(h : ∀ (a b : V) (e : a ⟶ b), F.map e.toPath =
eqToHom (congr_fun h_obj a) ≫ G.map e.toPath ≫ eqToHom (congr_fun h_obj.symm b)) :
F = G := by |
fapply Functor.ext
· intro X
rw [h_obj]
· intro X Y f
induction' f with Y' Z' g e ih
· erw [F.map_id, G.map_id, Category.id_comp, eqToHom_trans, eqToHom_refl]
· erw [F.map_comp g (Quiver.Hom.toPath e), G.map_comp g (Quiver.Hom.toPath e), ih, h]
simp only [Category.id_comp, eqToHom_refl, eqToHom_trans_assoc, Category.assoc]
| 0 |
import Batteries.Data.List.Lemmas
import Batteries.Data.Array.Basic
import Batteries.Tactic.SeqFocus
import Batteries.Util.ProofWanted
namespace Array
theorem forIn_eq_data_forIn [Monad m]
(as : Array α) (b : β) (f : α → β → m (ForInStep β)) :
forIn as b f = forIn as.data b f := by
let rec loop : ∀ {i h b j}, j + i = as.size →
Array.forIn.loop as f i h b = forIn (as.data.drop j) b f
| 0, _, _, _, rfl => by rw [List.drop_length]; rfl
| i+1, _, _, j, ij => by
simp only [forIn.loop, Nat.add]
have j_eq : j = size as - 1 - i := by simp [← ij, ← Nat.add_assoc]
have : as.size - 1 - i < as.size := j_eq ▸ ij ▸ Nat.lt_succ_of_le (Nat.le_add_right ..)
have : as[size as - 1 - i] :: as.data.drop (j + 1) = as.data.drop j := by
rw [j_eq]; exact List.get_cons_drop _ ⟨_, this⟩
simp only [← this, List.forIn_cons]; congr; funext x; congr; funext b
rw [loop (i := i)]; rw [← ij, Nat.succ_add]; rfl
conv => lhs; simp only [forIn, Array.forIn]
rw [loop (Nat.zero_add _)]; rfl
theorem zipWith_eq_zipWith_data (f : α → β → γ) (as : Array α) (bs : Array β) :
(as.zipWith bs f).data = as.data.zipWith f bs.data := by
let rec loop : ∀ (i : Nat) cs, i ≤ as.size → i ≤ bs.size →
(zipWithAux f as bs i cs).data = cs.data ++ (as.data.drop i).zipWith f (bs.data.drop i) := by
intro i cs hia hib
unfold zipWithAux
by_cases h : i = as.size ∨ i = bs.size
case pos =>
have : ¬(i < as.size) ∨ ¬(i < bs.size) := by
cases h <;> simp_all only [Nat.not_lt, Nat.le_refl, true_or, or_true]
-- Cleaned up aesop output below
simp_all only [Nat.not_lt]
cases h <;> [(cases this); (cases this)]
· simp_all only [Nat.le_refl, Nat.lt_irrefl, dite_false, List.drop_length,
List.zipWith_nil_left, List.append_nil]
· simp_all only [Nat.le_refl, Nat.lt_irrefl, dite_false, List.drop_length,
List.zipWith_nil_left, List.append_nil]
· simp_all only [Nat.le_refl, Nat.lt_irrefl, dite_false, List.drop_length,
List.zipWith_nil_right, List.append_nil]
split <;> simp_all only [Nat.not_lt]
· simp_all only [Nat.le_refl, Nat.lt_irrefl, dite_false, List.drop_length,
List.zipWith_nil_right, List.append_nil]
split <;> simp_all only [Nat.not_lt]
case neg =>
rw [not_or] at h
have has : i < as.size := Nat.lt_of_le_of_ne hia h.1
have hbs : i < bs.size := Nat.lt_of_le_of_ne hib h.2
simp only [has, hbs, dite_true]
rw [loop (i+1) _ has hbs, Array.push_data]
have h₁ : [f as[i] bs[i]] = List.zipWith f [as[i]] [bs[i]] := rfl
let i_as : Fin as.data.length := ⟨i, has⟩
let i_bs : Fin bs.data.length := ⟨i, hbs⟩
rw [h₁, List.append_assoc]
congr
rw [← List.zipWith_append (h := by simp), getElem_eq_data_get, getElem_eq_data_get]
show List.zipWith f ((List.get as.data i_as) :: List.drop (i_as + 1) as.data)
((List.get bs.data i_bs) :: List.drop (i_bs + 1) bs.data) =
List.zipWith f (List.drop i as.data) (List.drop i bs.data)
simp only [List.get_cons_drop]
termination_by as.size - i
simp [zipWith, loop 0 #[] (by simp) (by simp)]
theorem size_zipWith (as : Array α) (bs : Array β) (f : α → β → γ) :
(as.zipWith bs f).size = min as.size bs.size := by
rw [size_eq_length_data, zipWith_eq_zipWith_data, List.length_zipWith]
theorem zip_eq_zip_data (as : Array α) (bs : Array β) :
(as.zip bs).data = as.data.zip bs.data :=
zipWith_eq_zipWith_data Prod.mk as bs
theorem size_zip (as : Array α) (bs : Array β) :
(as.zip bs).size = min as.size bs.size :=
as.size_zipWith bs Prod.mk
theorem size_filter_le (p : α → Bool) (l : Array α) :
(l.filter p).size ≤ l.size := by
simp only [← data_length, filter_data]
apply List.length_filter_le
@[simp] theorem join_data {l : Array (Array α)} : l.join.data = (l.data.map data).join := by
dsimp [join]
simp only [foldl_eq_foldl_data]
generalize l.data = l
have : ∀ a : Array α, (List.foldl ?_ a l).data = a.data ++ ?_ := ?_
exact this #[]
induction l with
| nil => simp
| cons h => induction h.data <;> simp [*]
| .lake/packages/batteries/Batteries/Data/Array/Lemmas.lean | 106 | 113 | theorem mem_join : ∀ {L : Array (Array α)}, a ∈ L.join ↔ ∃ l, l ∈ L ∧ a ∈ l := by |
simp only [mem_def, join_data, List.mem_join, List.mem_map]
intro l
constructor
· rintro ⟨_, ⟨s, m, rfl⟩, h⟩
exact ⟨s, m, h⟩
· rintro ⟨s, h₁, h₂⟩
refine ⟨s.data, ⟨⟨s, h₁, rfl⟩, h₂⟩⟩
| 0 |
import Mathlib.Algebra.MvPolynomial.PDeriv
import Mathlib.Algebra.Polynomial.AlgebraMap
import Mathlib.Algebra.Polynomial.Derivative
import Mathlib.Data.Nat.Choose.Sum
import Mathlib.LinearAlgebra.LinearIndependent
import Mathlib.RingTheory.Polynomial.Pochhammer
#align_import ring_theory.polynomial.bernstein from "leanprover-community/mathlib"@"bbeb185db4ccee8ed07dc48449414ebfa39cb821"
noncomputable section
open Nat (choose)
open Polynomial (X)
open scoped Polynomial
variable (R : Type*) [CommRing R]
def bernsteinPolynomial (n ν : ℕ) : R[X] :=
(choose n ν : R[X]) * X ^ ν * (1 - X) ^ (n - ν)
#align bernstein_polynomial bernsteinPolynomial
example : bernsteinPolynomial ℤ 3 2 = 3 * X ^ 2 - 3 * X ^ 3 := by
norm_num [bernsteinPolynomial, choose]
ring
namespace bernsteinPolynomial
theorem eq_zero_of_lt {n ν : ℕ} (h : n < ν) : bernsteinPolynomial R n ν = 0 := by
simp [bernsteinPolynomial, Nat.choose_eq_zero_of_lt h]
#align bernstein_polynomial.eq_zero_of_lt bernsteinPolynomial.eq_zero_of_lt
section
variable {R} {S : Type*} [CommRing S]
@[simp]
theorem map (f : R →+* S) (n ν : ℕ) :
(bernsteinPolynomial R n ν).map f = bernsteinPolynomial S n ν := by simp [bernsteinPolynomial]
#align bernstein_polynomial.map bernsteinPolynomial.map
end
theorem flip (n ν : ℕ) (h : ν ≤ n) :
(bernsteinPolynomial R n ν).comp (1 - X) = bernsteinPolynomial R n (n - ν) := by
simp [bernsteinPolynomial, h, tsub_tsub_assoc, mul_right_comm]
#align bernstein_polynomial.flip bernsteinPolynomial.flip
theorem flip' (n ν : ℕ) (h : ν ≤ n) :
bernsteinPolynomial R n ν = (bernsteinPolynomial R n (n - ν)).comp (1 - X) := by
simp [← flip _ _ _ h, Polynomial.comp_assoc]
#align bernstein_polynomial.flip' bernsteinPolynomial.flip'
theorem eval_at_0 (n ν : ℕ) : (bernsteinPolynomial R n ν).eval 0 = if ν = 0 then 1 else 0 := by
rw [bernsteinPolynomial]
split_ifs with h
· subst h; simp
· simp [zero_pow h]
#align bernstein_polynomial.eval_at_0 bernsteinPolynomial.eval_at_0
theorem eval_at_1 (n ν : ℕ) : (bernsteinPolynomial R n ν).eval 1 = if ν = n then 1 else 0 := by
rw [bernsteinPolynomial]
split_ifs with h
· subst h; simp
· obtain hνn | hnν := Ne.lt_or_lt h
· simp [zero_pow $ Nat.sub_ne_zero_of_lt hνn]
· simp [Nat.choose_eq_zero_of_lt hnν]
#align bernstein_polynomial.eval_at_1 bernsteinPolynomial.eval_at_1
| Mathlib/RingTheory/Polynomial/Bernstein.lean | 102 | 131 | theorem derivative_succ_aux (n ν : ℕ) :
Polynomial.derivative (bernsteinPolynomial R (n + 1) (ν + 1)) =
(n + 1) * (bernsteinPolynomial R n ν - bernsteinPolynomial R n (ν + 1)) := by |
rw [bernsteinPolynomial]
suffices ((n + 1).choose (ν + 1) : R[X]) * ((↑(ν + 1 : ℕ) : R[X]) * X ^ ν) * (1 - X) ^ (n - ν) -
((n + 1).choose (ν + 1) : R[X]) * X ^ (ν + 1) * ((↑(n - ν) : R[X]) * (1 - X) ^ (n - ν - 1)) =
(↑(n + 1) : R[X]) * ((n.choose ν : R[X]) * X ^ ν * (1 - X) ^ (n - ν) -
(n.choose (ν + 1) : R[X]) * X ^ (ν + 1) * (1 - X) ^ (n - (ν + 1))) by
simpa [Polynomial.derivative_pow, ← sub_eq_add_neg, Nat.succ_sub_succ_eq_sub,
Polynomial.derivative_mul, Polynomial.derivative_natCast, zero_mul,
Nat.cast_add, algebraMap.coe_one, Polynomial.derivative_X, mul_one, zero_add,
Polynomial.derivative_sub, Polynomial.derivative_one, zero_sub, mul_neg, Nat.sub_zero,
bernsteinPolynomial, map_add, map_natCast, Nat.cast_one]
conv_rhs => rw [mul_sub]
-- We'll prove the two terms match up separately.
refine congr (congr_arg Sub.sub ?_) ?_
· simp only [← mul_assoc]
apply congr (congr_arg (· * ·) (congr (congr_arg (· * ·) _) rfl)) rfl
-- Now it's just about binomial coefficients
exact mod_cast congr_arg (fun m : ℕ => (m : R[X])) (Nat.succ_mul_choose_eq n ν).symm
· rw [← tsub_add_eq_tsub_tsub, ← mul_assoc, ← mul_assoc]; congr 1
rw [mul_comm, ← mul_assoc, ← mul_assoc]; congr 1
norm_cast
congr 1
convert (Nat.choose_mul_succ_eq n (ν + 1)).symm using 1
· -- Porting note: was
-- convert mul_comm _ _ using 2
-- simp
rw [mul_comm, Nat.succ_sub_succ_eq_sub]
· apply mul_comm
| 0 |
import Mathlib.FieldTheory.Separable
import Mathlib.RingTheory.IntegralDomain
import Mathlib.Algebra.CharP.Reduced
import Mathlib.Tactic.ApplyFun
#align_import field_theory.finite.basic from "leanprover-community/mathlib"@"12a85fac627bea918960da036049d611b1a3ee43"
variable {K : Type*} {R : Type*}
local notation "q" => Fintype.card K
open Finset
open scoped Polynomial
namespace FiniteField
theorem prod_univ_units_id_eq_neg_one [CommRing K] [IsDomain K] [Fintype Kˣ] :
∏ x : Kˣ, x = (-1 : Kˣ) := by
classical
have : (∏ x ∈ (@univ Kˣ _).erase (-1), x) = 1 :=
prod_involution (fun x _ => x⁻¹) (by simp)
(fun a => by simp (config := { contextual := true }) [Units.inv_eq_self_iff])
(fun a => by simp [@inv_eq_iff_eq_inv _ _ a]) (by simp)
rw [← insert_erase (mem_univ (-1 : Kˣ)), prod_insert (not_mem_erase _ _), this, mul_one]
#align finite_field.prod_univ_units_id_eq_neg_one FiniteField.prod_univ_units_id_eq_neg_one
set_option backward.synthInstance.canonInstances false in -- See https://github.com/leanprover-community/mathlib4/issues/12532
theorem card_cast_subgroup_card_ne_zero [Ring K] [NoZeroDivisors K] [Nontrivial K]
(G : Subgroup Kˣ) [Fintype G] : (Fintype.card G : K) ≠ 0 := by
let n := Fintype.card G
intro nzero
have ⟨p, char_p⟩ := CharP.exists K
have hd : p ∣ n := (CharP.cast_eq_zero_iff K p n).mp nzero
cases CharP.char_is_prime_or_zero K p with
| inr pzero =>
exact (Fintype.card_pos).ne' <| Nat.eq_zero_of_zero_dvd <| pzero ▸ hd
| inl pprime =>
have fact_pprime := Fact.mk pprime
-- G has an element x of order p by Cauchy's theorem
have ⟨x, hx⟩ := exists_prime_orderOf_dvd_card p hd
-- F has an element u (= ↑↑x) of order p
let u := ((x : Kˣ) : K)
have hu : orderOf u = p := by rwa [orderOf_units, Subgroup.orderOf_coe]
-- u ^ p = 1 implies (u - 1) ^ p = 0 and hence u = 1 ...
have h : u = 1 := by
rw [← sub_left_inj, sub_self 1]
apply pow_eq_zero (n := p)
rw [sub_pow_char_of_commute, one_pow, ← hu, pow_orderOf_eq_one, sub_self]
exact Commute.one_right u
-- ... meaning x didn't have order p after all, contradiction
apply pprime.one_lt.ne
rw [← hu, h, orderOf_one]
| Mathlib/FieldTheory/Finite/Basic.lean | 142 | 164 | theorem sum_subgroup_units_eq_zero [Ring K] [NoZeroDivisors K]
{G : Subgroup Kˣ} [Fintype G] (hg : G ≠ ⊥) :
∑ x : G, (x.val : K) = 0 := by |
rw [Subgroup.ne_bot_iff_exists_ne_one] at hg
rcases hg with ⟨a, ha⟩
-- The action of a on G as an embedding
let a_mul_emb : G ↪ G := mulLeftEmbedding a
-- ... and leaves G unchanged
have h_unchanged : Finset.univ.map a_mul_emb = Finset.univ := by simp
-- Therefore the sum of x over a G is the sum of a x over G
have h_sum_map := Finset.univ.sum_map a_mul_emb fun x => ((x : Kˣ) : K)
-- ... and the former is the sum of x over G.
-- By algebraic manipulation, we have Σ G, x = ∑ G, a x = a ∑ G, x
simp only [a_mul_emb, h_unchanged, Function.Embedding.coeFn_mk, Function.Embedding.toFun_eq_coe,
mulLeftEmbedding_apply, Submonoid.coe_mul, Subgroup.coe_toSubmonoid, Units.val_mul,
← Finset.mul_sum] at h_sum_map
-- thus one of (a - 1) or ∑ G, x is zero
have hzero : (((a : Kˣ) : K) - 1) = 0 ∨ ∑ x : ↥G, ((x : Kˣ) : K) = 0 := by
rw [← mul_eq_zero, sub_mul, ← h_sum_map, one_mul, sub_self]
apply Or.resolve_left hzero
contrapose! ha
ext
rwa [← sub_eq_zero]
| 0 |
import Mathlib.Analysis.Calculus.ContDiff.Bounds
import Mathlib.Analysis.Calculus.IteratedDeriv.Defs
import Mathlib.Analysis.Calculus.LineDeriv.Basic
import Mathlib.Analysis.LocallyConvex.WithSeminorms
import Mathlib.Analysis.Normed.Group.ZeroAtInfty
import Mathlib.Analysis.SpecialFunctions.Pow.Real
import Mathlib.Analysis.SpecialFunctions.JapaneseBracket
import Mathlib.Topology.Algebra.UniformFilterBasis
import Mathlib.Tactic.MoveAdd
#align_import analysis.schwartz_space from "leanprover-community/mathlib"@"e137999b2c6f2be388f4cd3bbf8523de1910cd2b"
noncomputable section
open scoped Nat NNReal
variable {𝕜 𝕜' D E F G V : Type*}
variable [NormedAddCommGroup E] [NormedSpace ℝ E]
variable [NormedAddCommGroup F] [NormedSpace ℝ F]
variable (E F)
structure SchwartzMap where
toFun : E → F
smooth' : ContDiff ℝ ⊤ toFun
decay' : ∀ k n : ℕ, ∃ C : ℝ, ∀ x, ‖x‖ ^ k * ‖iteratedFDeriv ℝ n toFun x‖ ≤ C
#align schwartz_map SchwartzMap
scoped[SchwartzMap] notation "𝓢(" E ", " F ")" => SchwartzMap E F
variable {E F}
namespace SchwartzMap
-- Porting note: removed
-- instance : Coe 𝓢(E, F) (E → F) := ⟨toFun⟩
instance instFunLike : FunLike 𝓢(E, F) E F where
coe f := f.toFun
coe_injective' f g h := by cases f; cases g; congr
#align schwartz_map.fun_like SchwartzMap.instFunLike
instance instCoeFun : CoeFun 𝓢(E, F) fun _ => E → F :=
DFunLike.hasCoeToFun
#align schwartz_map.has_coe_to_fun SchwartzMap.instCoeFun
theorem decay (f : 𝓢(E, F)) (k n : ℕ) :
∃ C : ℝ, 0 < C ∧ ∀ x, ‖x‖ ^ k * ‖iteratedFDeriv ℝ n f x‖ ≤ C := by
rcases f.decay' k n with ⟨C, hC⟩
exact ⟨max C 1, by positivity, fun x => (hC x).trans (le_max_left _ _)⟩
#align schwartz_map.decay SchwartzMap.decay
theorem smooth (f : 𝓢(E, F)) (n : ℕ∞) : ContDiff ℝ n f :=
f.smooth'.of_le le_top
#align schwartz_map.smooth SchwartzMap.smooth
@[continuity]
protected theorem continuous (f : 𝓢(E, F)) : Continuous f :=
(f.smooth 0).continuous
#align schwartz_map.continuous SchwartzMap.continuous
instance instContinuousMapClass : ContinuousMapClass 𝓢(E, F) E F where
map_continuous := SchwartzMap.continuous
protected theorem differentiable (f : 𝓢(E, F)) : Differentiable ℝ f :=
(f.smooth 1).differentiable rfl.le
#align schwartz_map.differentiable SchwartzMap.differentiable
protected theorem differentiableAt (f : 𝓢(E, F)) {x : E} : DifferentiableAt ℝ f x :=
f.differentiable.differentiableAt
#align schwartz_map.differentiable_at SchwartzMap.differentiableAt
@[ext]
theorem ext {f g : 𝓢(E, F)} (h : ∀ x, (f : E → F) x = g x) : f = g :=
DFunLike.ext f g h
#align schwartz_map.ext SchwartzMap.ext
section IsBigO
open Asymptotics Filter
variable (f : 𝓢(E, F))
| Mathlib/Analysis/Distribution/SchwartzSpace.lean | 145 | 153 | theorem isBigO_cocompact_zpow_neg_nat (k : ℕ) :
f =O[cocompact E] fun x => ‖x‖ ^ (-k : ℤ) := by |
obtain ⟨d, _, hd'⟩ := f.decay k 0
simp only [norm_iteratedFDeriv_zero] at hd'
simp_rw [Asymptotics.IsBigO, Asymptotics.IsBigOWith]
refine ⟨d, Filter.Eventually.filter_mono Filter.cocompact_le_cofinite ?_⟩
refine (Filter.eventually_cofinite_ne 0).mono fun x hx => ?_
rw [Real.norm_of_nonneg (zpow_nonneg (norm_nonneg _) _), zpow_neg, ← div_eq_mul_inv, le_div_iff']
exacts [hd' x, zpow_pos_of_pos (norm_pos_iff.mpr hx) _]
| 0 |
import Mathlib.Analysis.SpecificLimits.Basic
import Mathlib.Data.Rat.Denumerable
import Mathlib.Data.Set.Pointwise.Interval
import Mathlib.SetTheory.Cardinal.Continuum
#align_import data.real.cardinality from "leanprover-community/mathlib"@"7e7aaccf9b0182576cabdde36cf1b5ad3585b70d"
open Nat Set
open Cardinal
noncomputable section
namespace Cardinal
variable {c : ℝ} {f g : ℕ → Bool} {n : ℕ}
def cantorFunctionAux (c : ℝ) (f : ℕ → Bool) (n : ℕ) : ℝ :=
cond (f n) (c ^ n) 0
#align cardinal.cantor_function_aux Cardinal.cantorFunctionAux
@[simp]
theorem cantorFunctionAux_true (h : f n = true) : cantorFunctionAux c f n = c ^ n := by
simp [cantorFunctionAux, h]
#align cardinal.cantor_function_aux_tt Cardinal.cantorFunctionAux_true
@[simp]
theorem cantorFunctionAux_false (h : f n = false) : cantorFunctionAux c f n = 0 := by
simp [cantorFunctionAux, h]
#align cardinal.cantor_function_aux_ff Cardinal.cantorFunctionAux_false
theorem cantorFunctionAux_nonneg (h : 0 ≤ c) : 0 ≤ cantorFunctionAux c f n := by
cases h' : f n <;> simp [h']
apply pow_nonneg h
#align cardinal.cantor_function_aux_nonneg Cardinal.cantorFunctionAux_nonneg
theorem cantorFunctionAux_eq (h : f n = g n) :
cantorFunctionAux c f n = cantorFunctionAux c g n := by simp [cantorFunctionAux, h]
#align cardinal.cantor_function_aux_eq Cardinal.cantorFunctionAux_eq
theorem cantorFunctionAux_zero (f : ℕ → Bool) : cantorFunctionAux c f 0 = cond (f 0) 1 0 := by
cases h : f 0 <;> simp [h]
#align cardinal.cantor_function_aux_zero Cardinal.cantorFunctionAux_zero
theorem cantorFunctionAux_succ (f : ℕ → Bool) :
(fun n => cantorFunctionAux c f (n + 1)) = fun n =>
c * cantorFunctionAux c (fun n => f (n + 1)) n := by
ext n
cases h : f (n + 1) <;> simp [h, _root_.pow_succ']
#align cardinal.cantor_function_aux_succ Cardinal.cantorFunctionAux_succ
theorem summable_cantor_function (f : ℕ → Bool) (h1 : 0 ≤ c) (h2 : c < 1) :
Summable (cantorFunctionAux c f) := by
apply (summable_geometric_of_lt_one h1 h2).summable_of_eq_zero_or_self
intro n; cases h : f n <;> simp [h]
#align cardinal.summable_cantor_function Cardinal.summable_cantor_function
def cantorFunction (c : ℝ) (f : ℕ → Bool) : ℝ :=
∑' n, cantorFunctionAux c f n
#align cardinal.cantor_function Cardinal.cantorFunction
theorem cantorFunction_le (h1 : 0 ≤ c) (h2 : c < 1) (h3 : ∀ n, f n → g n) :
cantorFunction c f ≤ cantorFunction c g := by
apply tsum_le_tsum _ (summable_cantor_function f h1 h2) (summable_cantor_function g h1 h2)
intro n; cases h : f n
· simp [h, cantorFunctionAux_nonneg h1]
replace h3 : g n = true := h3 n h; simp [h, h3]
#align cardinal.cantor_function_le Cardinal.cantorFunction_le
theorem cantorFunction_succ (f : ℕ → Bool) (h1 : 0 ≤ c) (h2 : c < 1) :
cantorFunction c f = cond (f 0) 1 0 + c * cantorFunction c fun n => f (n + 1) := by
rw [cantorFunction, tsum_eq_zero_add (summable_cantor_function f h1 h2)]
rw [cantorFunctionAux_succ, tsum_mul_left, cantorFunctionAux, _root_.pow_zero]
rfl
#align cardinal.cantor_function_succ Cardinal.cantorFunction_succ
| Mathlib/Data/Real/Cardinality.lean | 123 | 164 | theorem increasing_cantorFunction (h1 : 0 < c) (h2 : c < 1 / 2) {n : ℕ} {f g : ℕ → Bool}
(hn : ∀ k < n, f k = g k) (fn : f n = false) (gn : g n = true) :
cantorFunction c f < cantorFunction c g := by |
have h3 : c < 1 := by
apply h2.trans
norm_num
induction' n with n ih generalizing f g
· let f_max : ℕ → Bool := fun n => Nat.rec false (fun _ _ => true) n
have hf_max : ∀ n, f n → f_max n := by
intro n hn
cases n
· rw [fn] at hn
contradiction
apply rfl
let g_min : ℕ → Bool := fun n => Nat.rec true (fun _ _ => false) n
have hg_min : ∀ n, g_min n → g n := by
intro n hn
cases n
· rw [gn]
simp at hn
apply (cantorFunction_le (le_of_lt h1) h3 hf_max).trans_lt
refine lt_of_lt_of_le ?_ (cantorFunction_le (le_of_lt h1) h3 hg_min)
have : c / (1 - c) < 1 := by
rw [div_lt_one, lt_sub_iff_add_lt]
· convert _root_.add_lt_add h2 h2
norm_num
rwa [sub_pos]
convert this
· rw [cantorFunction_succ _ (le_of_lt h1) h3, div_eq_mul_inv, ←
tsum_geometric_of_lt_one (le_of_lt h1) h3]
apply zero_add
· refine (tsum_eq_single 0 ?_).trans ?_
· intro n hn
cases n
· contradiction
rfl
· exact cantorFunctionAux_zero _
rw [cantorFunction_succ f (le_of_lt h1) h3, cantorFunction_succ g (le_of_lt h1) h3]
rw [hn 0 <| zero_lt_succ n]
apply add_lt_add_left
rw [mul_lt_mul_left h1]
exact ih (fun k hk => hn _ <| Nat.succ_lt_succ hk) fn gn
| 0 |
import Mathlib.Data.List.Chain
import Mathlib.Data.List.Enum
import Mathlib.Data.List.Nodup
import Mathlib.Data.List.Pairwise
import Mathlib.Data.List.Zip
#align_import data.list.range from "leanprover-community/mathlib"@"7b78d1776212a91ecc94cf601f83bdcc46b04213"
set_option autoImplicit true
universe u
open Nat
namespace List
variable {α : Type u}
@[simp] theorem range'_one {step} : range' s 1 step = [s] := rfl
#align list.length_range' List.length_range'
#align list.range'_eq_nil List.range'_eq_nil
#align list.mem_range' List.mem_range'_1
#align list.map_add_range' List.map_add_range'
#align list.map_sub_range' List.map_sub_range'
#align list.chain_succ_range' List.chain_succ_range'
#align list.chain_lt_range' List.chain_lt_range'
theorem pairwise_lt_range' : ∀ s n (step := 1) (_ : 0 < step := by simp),
Pairwise (· < ·) (range' s n step)
| _, 0, _, _ => Pairwise.nil
| s, n + 1, _, h => chain_iff_pairwise.1 (chain_lt_range' s n h)
#align list.pairwise_lt_range' List.pairwise_lt_range'
theorem nodup_range' (s n : ℕ) (step := 1) (h : 0 < step := by simp) : Nodup (range' s n step) :=
(pairwise_lt_range' s n step h).imp _root_.ne_of_lt
#align list.nodup_range' List.nodup_range'
#align list.range'_append List.range'_append
#align list.range'_sublist_right List.range'_sublist_right
#align list.range'_subset_right List.range'_subset_right
#align list.nth_range' List.get?_range'
set_option linter.deprecated false in
@[simp]
theorem nthLe_range' {n m step} (i) (H : i < (range' n m step).length) :
nthLe (range' n m step) i H = n + step * i := get_range' i H
set_option linter.deprecated false in
theorem nthLe_range'_1 {n m} (i) (H : i < (range' n m).length) :
nthLe (range' n m) i H = n + i := by simp
#align list.nth_le_range' List.nthLe_range'_1
#align list.range'_concat List.range'_concat
#align list.range_core List.range.loop
#align list.range_core_range' List.range_loop_range'
#align list.range_eq_range' List.range_eq_range'
#align list.range_succ_eq_map List.range_succ_eq_map
#align list.range'_eq_map_range List.range'_eq_map_range
#align list.length_range List.length_range
#align list.range_eq_nil List.range_eq_nil
theorem pairwise_lt_range (n : ℕ) : Pairwise (· < ·) (range n) := by
simp (config := {decide := true}) only [range_eq_range', pairwise_lt_range']
#align list.pairwise_lt_range List.pairwise_lt_range
theorem pairwise_le_range (n : ℕ) : Pairwise (· ≤ ·) (range n) :=
Pairwise.imp (@le_of_lt ℕ _) (pairwise_lt_range _)
#align list.pairwise_le_range List.pairwise_le_range
theorem take_range (m n : ℕ) : take m (range n) = range (min m n) := by
apply List.ext_get
· simp
· simp (config := { contextual := true }) [← get_take, Nat.lt_min]
theorem nodup_range (n : ℕ) : Nodup (range n) := by
simp (config := {decide := true}) only [range_eq_range', nodup_range']
#align list.nodup_range List.nodup_range
#align list.range_sublist List.range_sublist
#align list.range_subset List.range_subset
#align list.mem_range List.mem_range
#align list.not_mem_range_self List.not_mem_range_self
#align list.self_mem_range_succ List.self_mem_range_succ
#align list.nth_range List.get?_range
#align list.range_succ List.range_succ
#align list.range_zero List.range_zero
theorem chain'_range_succ (r : ℕ → ℕ → Prop) (n : ℕ) :
Chain' r (range n.succ) ↔ ∀ m < n, r m m.succ := by
rw [range_succ]
induction' n with n hn
· simp
· rw [range_succ]
simp only [append_assoc, singleton_append, chain'_append_cons_cons, chain'_singleton,
and_true_iff]
rw [hn, forall_lt_succ]
#align list.chain'_range_succ List.chain'_range_succ
| Mathlib/Data/List/Range.lean | 115 | 118 | theorem chain_range_succ (r : ℕ → ℕ → Prop) (n a : ℕ) :
Chain r a (range n.succ) ↔ r a 0 ∧ ∀ m < n, r m m.succ := by |
rw [range_succ_eq_map, chain_cons, and_congr_right_iff, ← chain'_range_succ, range_succ_eq_map]
exact fun _ => Iff.rfl
| 0 |
import Mathlib.Data.Nat.Choose.Basic
import Mathlib.Data.Nat.Prime
#align_import data.nat.choose.dvd from "leanprover-community/mathlib"@"966e0cf0685c9cedf8a3283ac69eef4d5f2eaca2"
namespace Nat
open Nat
namespace Prime
variable {p a b k : ℕ}
| Mathlib/Data/Nat/Choose/Dvd.lean | 24 | 29 | theorem dvd_choose_add (hp : Prime p) (hap : a < p) (hbp : b < p) (h : p ≤ a + b) :
p ∣ choose (a + b) a := by |
have h₁ : p ∣ (a + b)! := hp.dvd_factorial.2 h
rw [← add_choose_mul_factorial_mul_factorial, ← choose_symm_add, hp.dvd_mul, hp.dvd_mul,
hp.dvd_factorial, hp.dvd_factorial] at h₁
exact (h₁.resolve_right hbp.not_le).resolve_right hap.not_le
| 0 |
import Mathlib.NumberTheory.SmoothNumbers
import Mathlib.Analysis.PSeries
open Set Nat
open scoped Topology
-- This needs `Mathlib.Analysis.RCLike.Basic`, so we put it here
-- instead of in `Mathlib.NumberTheory.SmoothNumbers`.
lemma Nat.roughNumbersUpTo_card_le' (N k : ℕ) :
(roughNumbersUpTo N k).card ≤
N * (N.succ.primesBelow \ k.primesBelow).sum (fun p ↦ (1 : ℝ) / p) := by
simp_rw [Finset.mul_sum, mul_one_div]
exact (Nat.cast_le.mpr <| roughNumbersUpTo_card_le N k).trans <|
(cast_sum (β := ℝ) ..) ▸ Finset.sum_le_sum fun n _ ↦ cast_div_le
lemma one_half_le_sum_primes_ge_one_div (k : ℕ) :
1 / 2 ≤ ∑ p ∈ (4 ^ (k.primesBelow.card + 1)).succ.primesBelow \ k.primesBelow,
(1 / p : ℝ) := by
set m : ℕ := 2 ^ k.primesBelow.card
set N₀ : ℕ := 2 * m ^ 2 with hN₀
let S : ℝ := ((2 * N₀).succ.primesBelow \ k.primesBelow).sum (fun p ↦ (1 / p : ℝ))
suffices 1 / 2 ≤ S by
convert this using 5
rw [show 4 = 2 ^ 2 by norm_num, pow_right_comm]
ring
suffices 2 * N₀ ≤ m * (2 * N₀).sqrt + 2 * N₀ * S by
rwa [hN₀, ← mul_assoc, ← pow_two 2, ← mul_pow, sqrt_eq', ← sub_le_iff_le_add',
cast_mul, cast_mul, cast_pow, cast_two,
show (2 * (2 * m ^ 2) - m * (2 * m) : ℝ) = 2 * (2 * m ^ 2) * (1 / 2) by ring,
_root_.mul_le_mul_left <| by positivity] at this
calc (2 * N₀ : ℝ)
_ = ((2 * N₀).smoothNumbersUpTo k).card + ((2 * N₀).roughNumbersUpTo k).card := by
exact_mod_cast ((2 * N₀).smoothNumbersUpTo_card_add_roughNumbersUpTo_card k).symm
_ ≤ m * (2 * N₀).sqrt + ((2 * N₀).roughNumbersUpTo k).card := by
exact_mod_cast Nat.add_le_add_right ((2 * N₀).smoothNumbersUpTo_card_le k) _
_ ≤ m * (2 * N₀).sqrt + 2 * N₀ * S := add_le_add_left ?_ _
exact_mod_cast roughNumbersUpTo_card_le' (2 * N₀) k
theorem not_summable_one_div_on_primes :
¬ Summable (indicator {p | p.Prime} (fun n : ℕ ↦ (1 : ℝ) / n)) := by
intro h
obtain ⟨k, hk⟩ := h.nat_tsum_vanishing (Iio_mem_nhds one_half_pos : Iio (1 / 2 : ℝ) ∈ 𝓝 0)
specialize hk ({p | Nat.Prime p} ∩ {p | k ≤ p}) inter_subset_right
rw [tsum_subtype, indicator_indicator, inter_eq_left.mpr fun n hn ↦ hn.1, mem_Iio] at hk
have h' : Summable (indicator ({p | Nat.Prime p} ∩ {p | k ≤ p}) fun n ↦ (1 : ℝ) / n) := by
convert h.indicator {n : ℕ | k ≤ n} using 1
simp only [indicator_indicator, inter_comm]
refine ((one_half_le_sum_primes_ge_one_div k).trans_lt <| LE.le.trans_lt ?_ hk).false
convert sum_le_tsum (primesBelow ((4 ^ (k.primesBelow.card + 1)).succ) \ primesBelow k)
(fun n _ ↦ indicator_nonneg (fun p _ ↦ by positivity) _) h' using 2 with p hp
obtain ⟨hp₁, hp₂⟩ := mem_setOf_eq ▸ Finset.mem_sdiff.mp hp
have hpp := prime_of_mem_primesBelow hp₁
refine (indicator_of_mem (mem_def.mpr ⟨hpp, ?_⟩) fun n : ℕ ↦ (1 / n : ℝ)).symm
exact not_lt.mp <| (not_and_or.mp <| (not_congr mem_primesBelow).mp hp₂).neg_resolve_right hpp
| Mathlib/NumberTheory/SumPrimeReciprocals.lean | 82 | 83 | theorem Nat.Primes.not_summable_one_div : ¬ Summable (fun p : Nat.Primes ↦ (1 / p : ℝ)) := by |
convert summable_subtype_iff_indicator.mp.mt not_summable_one_div_on_primes
| 0 |
import Mathlib.Analysis.SpecialFunctions.ExpDeriv
#align_import analysis.ODE.gronwall from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] {F : Type*} [NormedAddCommGroup F]
[NormedSpace ℝ F]
open Metric Set Asymptotics Filter Real
open scoped Classical Topology NNReal
noncomputable def gronwallBound (δ K ε x : ℝ) : ℝ :=
if K = 0 then δ + ε * x else δ * exp (K * x) + ε / K * (exp (K * x) - 1)
#align gronwall_bound gronwallBound
theorem gronwallBound_K0 (δ ε : ℝ) : gronwallBound δ 0 ε = fun x => δ + ε * x :=
funext fun _ => if_pos rfl
set_option linter.uppercaseLean3 false in
#align gronwall_bound_K0 gronwallBound_K0
theorem gronwallBound_of_K_ne_0 {δ K ε : ℝ} (hK : K ≠ 0) :
gronwallBound δ K ε = fun x => δ * exp (K * x) + ε / K * (exp (K * x) - 1) :=
funext fun _ => if_neg hK
set_option linter.uppercaseLean3 false in
#align gronwall_bound_of_K_ne_0 gronwallBound_of_K_ne_0
theorem hasDerivAt_gronwallBound (δ K ε x : ℝ) :
HasDerivAt (gronwallBound δ K ε) (K * gronwallBound δ K ε x + ε) x := by
by_cases hK : K = 0
· subst K
simp only [gronwallBound_K0, zero_mul, zero_add]
convert ((hasDerivAt_id x).const_mul ε).const_add δ
rw [mul_one]
· simp only [gronwallBound_of_K_ne_0 hK]
convert (((hasDerivAt_id x).const_mul K).exp.const_mul δ).add
((((hasDerivAt_id x).const_mul K).exp.sub_const 1).const_mul (ε / K)) using 1
simp only [id, mul_add, (mul_assoc _ _ _).symm, mul_comm _ K, mul_div_cancel₀ _ hK]
ring
#align has_deriv_at_gronwall_bound hasDerivAt_gronwallBound
theorem hasDerivAt_gronwallBound_shift (δ K ε x a : ℝ) :
HasDerivAt (fun y => gronwallBound δ K ε (y - a)) (K * gronwallBound δ K ε (x - a) + ε) x := by
convert (hasDerivAt_gronwallBound δ K ε _).comp x ((hasDerivAt_id x).sub_const a) using 1
rw [id, mul_one]
#align has_deriv_at_gronwall_bound_shift hasDerivAt_gronwallBound_shift
theorem gronwallBound_x0 (δ K ε : ℝ) : gronwallBound δ K ε 0 = δ := by
by_cases hK : K = 0
· simp only [gronwallBound, if_pos hK, mul_zero, add_zero]
· simp only [gronwallBound, if_neg hK, mul_zero, exp_zero, sub_self, mul_one,
add_zero]
#align gronwall_bound_x0 gronwallBound_x0
| Mathlib/Analysis/ODE/Gronwall.lean | 86 | 89 | theorem gronwallBound_ε0 (δ K x : ℝ) : gronwallBound δ K 0 x = δ * exp (K * x) := by |
by_cases hK : K = 0
· simp only [gronwallBound_K0, hK, zero_mul, exp_zero, add_zero, mul_one]
· simp only [gronwallBound_of_K_ne_0 hK, zero_div, zero_mul, add_zero]
| 0 |
import Mathlib.CategoryTheory.Closed.Cartesian
import Mathlib.CategoryTheory.Limits.Preserves.Shapes.BinaryProducts
import Mathlib.CategoryTheory.Adjunction.FullyFaithful
#align_import category_theory.closed.functor from "leanprover-community/mathlib"@"cea27692b3fdeb328a2ddba6aabf181754543184"
noncomputable section
namespace CategoryTheory
open Category Limits CartesianClosed
universe v u u'
variable {C : Type u} [Category.{v} C]
variable {D : Type u'} [Category.{v} D]
variable [HasFiniteProducts C] [HasFiniteProducts D]
variable (F : C ⥤ D) {L : D ⥤ C}
def frobeniusMorphism (h : L ⊣ F) (A : C) :
prod.functor.obj (F.obj A) ⋙ L ⟶ L ⋙ prod.functor.obj A :=
prodComparisonNatTrans L (F.obj A) ≫ whiskerLeft _ (prod.functor.map (h.counit.app _))
#align category_theory.frobenius_morphism CategoryTheory.frobeniusMorphism
instance frobeniusMorphism_iso_of_preserves_binary_products (h : L ⊣ F) (A : C)
[PreservesLimitsOfShape (Discrete WalkingPair) L] [F.Full] [F.Faithful] :
IsIso (frobeniusMorphism F h A) :=
suffices ∀ (X : D), IsIso ((frobeniusMorphism F h A).app X) from NatIso.isIso_of_isIso_app _
fun B ↦ by dsimp [frobeniusMorphism]; infer_instance
#align category_theory.frobenius_morphism_iso_of_preserves_binary_products CategoryTheory.frobeniusMorphism_iso_of_preserves_binary_products
variable [CartesianClosed C] [CartesianClosed D]
variable [PreservesLimitsOfShape (Discrete WalkingPair) F]
def expComparison (A : C) : exp A ⋙ F ⟶ F ⋙ exp (F.obj A) :=
transferNatTrans (exp.adjunction A) (exp.adjunction (F.obj A)) (prodComparisonNatIso F A).inv
#align category_theory.exp_comparison CategoryTheory.expComparison
theorem expComparison_ev (A B : C) :
Limits.prod.map (𝟙 (F.obj A)) ((expComparison F A).app B) ≫ (exp.ev (F.obj A)).app (F.obj B) =
inv (prodComparison F _ _) ≫ F.map ((exp.ev _).app _) := by
convert transferNatTrans_counit _ _ (prodComparisonNatIso F A).inv B using 2
apply IsIso.inv_eq_of_hom_inv_id -- Porting note: was `ext`
simp only [Limits.prodComparisonNatIso_inv, asIso_inv, NatIso.isIso_inv_app, IsIso.hom_inv_id]
#align category_theory.exp_comparison_ev CategoryTheory.expComparison_ev
theorem coev_expComparison (A B : C) :
F.map ((exp.coev A).app B) ≫ (expComparison F A).app (A ⨯ B) =
(exp.coev _).app (F.obj B) ≫ (exp (F.obj A)).map (inv (prodComparison F A B)) := by
convert unit_transferNatTrans _ _ (prodComparisonNatIso F A).inv B using 3
apply IsIso.inv_eq_of_hom_inv_id -- Porting note: was `ext`
dsimp
simp
#align category_theory.coev_exp_comparison CategoryTheory.coev_expComparison
theorem uncurry_expComparison (A B : C) :
CartesianClosed.uncurry ((expComparison F A).app B) =
inv (prodComparison F _ _) ≫ F.map ((exp.ev _).app _) := by
rw [uncurry_eq, expComparison_ev]
#align category_theory.uncurry_exp_comparison CategoryTheory.uncurry_expComparison
theorem expComparison_whiskerLeft {A A' : C} (f : A' ⟶ A) :
expComparison F A ≫ whiskerLeft _ (pre (F.map f)) =
whiskerRight (pre f) _ ≫ expComparison F A' := by
ext B
dsimp
apply uncurry_injective
rw [uncurry_natural_left, uncurry_natural_left, uncurry_expComparison, uncurry_pre,
prod.map_swap_assoc, ← F.map_id, expComparison_ev, ← F.map_id, ←
prodComparison_inv_natural_assoc, ← prodComparison_inv_natural_assoc, ← F.map_comp, ←
F.map_comp, prod_map_pre_app_comp_ev]
#align category_theory.exp_comparison_whisker_left CategoryTheory.expComparison_whiskerLeft
class CartesianClosedFunctor : Prop where
comparison_iso : ∀ A, IsIso (expComparison F A)
#align category_theory.cartesian_closed_functor CategoryTheory.CartesianClosedFunctor
attribute [instance] CartesianClosedFunctor.comparison_iso
theorem frobeniusMorphism_mate (h : L ⊣ F) (A : C) :
transferNatTransSelf (h.comp (exp.adjunction A)) ((exp.adjunction (F.obj A)).comp h)
(frobeniusMorphism F h A) =
expComparison F A := by
rw [← Equiv.eq_symm_apply]
ext B : 2
dsimp [frobeniusMorphism, transferNatTransSelf, transferNatTrans, Adjunction.comp]
simp only [id_comp, comp_id]
rw [← L.map_comp_assoc, prod.map_id_comp, assoc]
-- Porting note: need to use `erw` here.
-- https://github.com/leanprover-community/mathlib4/issues/5164
erw [expComparison_ev]
rw [prod.map_id_comp, assoc, ← F.map_id, ← prodComparison_inv_natural_assoc, ← F.map_comp]
-- Porting note: need to use `erw` here.
-- https://github.com/leanprover-community/mathlib4/issues/5164
erw [exp.ev_coev]
rw [F.map_id (A ⨯ L.obj B), comp_id]
ext
· rw [assoc, assoc, ← h.counit_naturality, ← L.map_comp_assoc, assoc, inv_prodComparison_map_fst]
simp
· rw [assoc, assoc, ← h.counit_naturality, ← L.map_comp_assoc, assoc, inv_prodComparison_map_snd]
simp
#align category_theory.frobenius_morphism_mate CategoryTheory.frobeniusMorphism_mate
| Mathlib/CategoryTheory/Closed/Functor.lean | 156 | 159 | theorem frobeniusMorphism_iso_of_expComparison_iso (h : L ⊣ F) (A : C)
[i : IsIso (expComparison F A)] : IsIso (frobeniusMorphism F h A) := by |
rw [← frobeniusMorphism_mate F h] at i
exact @transferNatTransSelf_of_iso _ _ _ _ _ _ _ _ _ _ _ i
| 0 |
import Mathlib.LinearAlgebra.Dimension.StrongRankCondition
import Mathlib.LinearAlgebra.FreeModule.Basic
import Mathlib.LinearAlgebra.FreeModule.Finite.Basic
#align_import linear_algebra.dimension from "leanprover-community/mathlib"@"47a5f8186becdbc826190ced4312f8199f9db6a5"
noncomputable section
universe u v v' w
open Cardinal Basis Submodule Function Set DirectSum FiniteDimensional
section Tower
variable (F : Type u) (K : Type v) (A : Type w)
variable [Ring F] [Ring K] [AddCommGroup A]
variable [Module F K] [Module K A] [Module F A] [IsScalarTower F K A]
variable [StrongRankCondition F] [StrongRankCondition K] [Module.Free F K] [Module.Free K A]
theorem lift_rank_mul_lift_rank :
Cardinal.lift.{w} (Module.rank F K) * Cardinal.lift.{v} (Module.rank K A) =
Cardinal.lift.{v} (Module.rank F A) := by
let b := Module.Free.chooseBasis F K
let c := Module.Free.chooseBasis K A
rw [← (Module.rank F K).lift_id, ← b.mk_eq_rank, ← (Module.rank K A).lift_id, ← c.mk_eq_rank,
← lift_umax.{w, v}, ← (b.smul c).mk_eq_rank, mk_prod, lift_mul, lift_lift, lift_lift, lift_lift,
lift_lift, lift_umax.{v, w}]
#align lift_rank_mul_lift_rank lift_rank_mul_lift_rank
theorem rank_mul_rank (A : Type v) [AddCommGroup A]
[Module K A] [Module F A] [IsScalarTower F K A] [Module.Free K A] :
Module.rank F K * Module.rank K A = Module.rank F A := by
convert lift_rank_mul_lift_rank F K A <;> rw [lift_id]
#align rank_mul_rank rank_mul_rank
| Mathlib/LinearAlgebra/Dimension/Free.lean | 63 | 66 | theorem FiniteDimensional.finrank_mul_finrank : finrank F K * finrank K A = finrank F A := by |
simp_rw [finrank]
rw [← toNat_lift.{w} (Module.rank F K), ← toNat_lift.{v} (Module.rank K A), ← toNat_mul,
lift_rank_mul_lift_rank, toNat_lift]
| 0 |
import Mathlib.Topology.Baire.Lemmas
import Mathlib.Topology.Algebra.Group.Basic
open scoped Topology Pointwise
open MulAction Set Function
variable {G X : Type*} [TopologicalSpace G] [TopologicalSpace X]
[Group G] [TopologicalGroup G] [MulAction G X]
[SigmaCompactSpace G] [BaireSpace X] [T2Space X]
[ContinuousSMul G X] [IsPretransitive G X]
@[to_additive "Consider a sigma-compact additive group acting continuously and transitively on a
Baire space. Then the orbit map is open around zero. It follows in
`isOpenMap_vadd_of_sigmaCompact` that it is open around any point."]
theorem smul_singleton_mem_nhds_of_sigmaCompact
{U : Set G} (hU : U ∈ 𝓝 1) (x : X) : U • {x} ∈ 𝓝 x := by
obtain ⟨V, V_mem, V_closed, V_symm, VU⟩ : ∃ V ∈ 𝓝 (1 : G), IsClosed V ∧ V⁻¹ = V ∧ V * V ⊆ U :=
exists_closed_nhds_one_inv_eq_mul_subset hU
obtain ⟨s, s_count, hs⟩ : ∃ (s : Set G), s.Countable ∧ ⋃ g ∈ s, g • V = univ := by
apply countable_cover_nhds_of_sigma_compact (fun g ↦ ?_)
convert smul_mem_nhds g V_mem
simp only [smul_eq_mul, mul_one]
let K : ℕ → Set G := compactCovering G
let F : ℕ × s → Set X := fun p ↦ (K p.1 ∩ (p.2 : G) • V) • ({x} : Set X)
obtain ⟨⟨n, ⟨g, hg⟩⟩, hi⟩ : ∃ i, (interior (F i)).Nonempty := by
have : Nonempty X := ⟨x⟩
have : Encodable s := Countable.toEncodable s_count
apply nonempty_interior_of_iUnion_of_closed
· rintro ⟨n, ⟨g, hg⟩⟩
apply IsCompact.isClosed
suffices H : IsCompact ((fun (g : G) ↦ g • x) '' (K n ∩ g • V)) by
simpa only [F, smul_singleton] using H
apply IsCompact.image
· exact (isCompact_compactCovering G n).inter_right (V_closed.smul g)
· exact continuous_id.smul continuous_const
· apply eq_univ_iff_forall.2 (fun y ↦ ?_)
obtain ⟨h, rfl⟩ : ∃ h, h • x = y := exists_smul_eq G x y
obtain ⟨n, hn⟩ : ∃ n, h ∈ K n := exists_mem_compactCovering h
obtain ⟨g, gs, hg⟩ : ∃ g ∈ s, h ∈ g • V := exists_set_mem_of_union_eq_top s _ hs _
simp only [F, smul_singleton, mem_iUnion, mem_image, mem_inter_iff, Prod.exists,
Subtype.exists, exists_prop]
exact ⟨n, g, gs, h, ⟨hn, hg⟩, rfl⟩
have I : (interior ((g • V) • {x})).Nonempty := by
apply hi.mono
apply interior_mono
exact smul_subset_smul_right inter_subset_right
obtain ⟨y, hy⟩ : (interior (V • ({x} : Set X))).Nonempty := by
rw [smul_assoc, interior_smul] at I
exact smul_set_nonempty.1 I
obtain ⟨g', hg', rfl⟩ : ∃ g' ∈ V, g' • x = y := by simpa using interior_subset hy
have J : (g' ⁻¹ • V) • {x} ∈ 𝓝 x := by
apply mem_interior_iff_mem_nhds.1
rwa [smul_assoc, interior_smul, mem_inv_smul_set_iff]
have : (g'⁻¹ • V) • {x} ⊆ U • ({x} : Set X) := by
apply smul_subset_smul_right
apply Subset.trans (smul_set_subset_smul (inv_mem_inv.2 hg')) ?_
rw [V_symm]
exact VU
exact Filter.mem_of_superset J this
@[to_additive "Consider a sigma-compact additive group acting continuously and transitively on a
Baire space. Then the orbit map is open. This is a version of the open mapping theorem, valid
notably for the action of a sigma-compact locally compact group on a locally compact space."]
theorem isOpenMap_smul_of_sigmaCompact (x : X) : IsOpenMap (fun (g : G) ↦ g • x) := by
simp_rw [isOpenMap_iff_nhds_le, Filter.le_map_iff]
intro g U hU
have : (· • x) = (· • (g • x)) ∘ (· * g⁻¹) := by
ext g
simp [smul_smul]
rw [this, image_comp, ← smul_singleton]
apply smul_singleton_mem_nhds_of_sigmaCompact
simpa using isOpenMap_mul_right g⁻¹ |>.image_mem_nhds hU
@[to_additive]
| Mathlib/Topology/Algebra/Group/OpenMapping.lean | 112 | 121 | theorem MonoidHom.isOpenMap_of_sigmaCompact
{H : Type*} [Group H] [TopologicalSpace H] [BaireSpace H] [T2Space H] [ContinuousMul H]
(f : G →* H) (hf : Function.Surjective f) (h'f : Continuous f) :
IsOpenMap f := by |
let A : MulAction G H := MulAction.compHom _ f
have : ContinuousSMul G H := continuousSMul_compHom h'f
have : IsPretransitive G H := isPretransitive_compHom hf
have : f = (fun (g : G) ↦ g • (1 : H)) := by simp [MulAction.compHom_smul_def]
rw [this]
exact isOpenMap_smul_of_sigmaCompact _
| 0 |
import Mathlib.Analysis.SpecialFunctions.PolarCoord
import Mathlib.Analysis.SpecialFunctions.Gamma.Basic
open Real Set MeasureTheory MeasureTheory.Measure
section real
| Mathlib/MeasureTheory/Integral/Gamma.lean | 21 | 37 | theorem integral_rpow_mul_exp_neg_rpow {p q : ℝ} (hp : 0 < p) (hq : - 1 < q) :
∫ x in Ioi (0:ℝ), x ^ q * exp (- x ^ p) = (1 / p) * Gamma ((q + 1) / p) := by |
calc
_ = ∫ (x : ℝ) in Ioi 0, (1 / p * x ^ (1 / p - 1)) • ((x ^ (1 / p)) ^ q * exp (-x)) := by
rw [← integral_comp_rpow_Ioi _ (one_div_ne_zero (ne_of_gt hp)),
abs_eq_self.mpr (le_of_lt (one_div_pos.mpr hp))]
refine setIntegral_congr measurableSet_Ioi (fun _ hx => ?_)
rw [← rpow_mul (le_of_lt hx) _ p, one_div_mul_cancel (ne_of_gt hp), rpow_one]
_ = ∫ (x : ℝ) in Ioi 0, 1 / p * exp (-x) * x ^ (1 / p - 1 + q / p) := by
simp_rw [smul_eq_mul, mul_assoc]
refine setIntegral_congr measurableSet_Ioi (fun _ hx => ?_)
rw [← rpow_mul (le_of_lt hx), div_mul_eq_mul_div, one_mul, rpow_add hx]
ring_nf
_ = (1 / p) * Gamma ((q + 1) / p) := by
rw [Gamma_eq_integral (div_pos (neg_lt_iff_pos_add.mp hq) hp)]
simp_rw [show 1 / p - 1 + q / p = (q + 1) / p - 1 by field_simp; ring, ← integral_mul_left,
← mul_assoc]
| 0 |
import Mathlib.CategoryTheory.Filtered.Connected
import Mathlib.CategoryTheory.Limits.TypesFiltered
import Mathlib.CategoryTheory.Limits.Final
universe v₁ v₂ u₁ u₂
namespace CategoryTheory
open CategoryTheory.Limits CategoryTheory.Functor Opposite
section ArbitraryUniverses
variable {C : Type u₁} [Category.{v₁} C] {D : Type u₂} [Category.{v₂} D] (F : C ⥤ D)
theorem Functor.final_of_isFiltered_structuredArrow [∀ d, IsFiltered (StructuredArrow d F)] :
Final F where
out _ := IsFiltered.isConnected _
theorem Functor.initial_of_isCofiltered_costructuredArrow
[∀ d, IsCofiltered (CostructuredArrow F d)] : Initial F where
out _ := IsCofiltered.isConnected _
theorem isFiltered_structuredArrow_of_isFiltered_of_exists [IsFilteredOrEmpty C]
(h₁ : ∀ d, ∃ c, Nonempty (d ⟶ F.obj c)) (h₂ : ∀ {d : D} {c : C} (s s' : d ⟶ F.obj c),
∃ (c' : C) (t : c ⟶ c'), s ≫ F.map t = s' ≫ F.map t) (d : D) :
IsFiltered (StructuredArrow d F) := by
have : Nonempty (StructuredArrow d F) := by
obtain ⟨c, ⟨f⟩⟩ := h₁ d
exact ⟨.mk f⟩
suffices IsFilteredOrEmpty (StructuredArrow d F) from IsFiltered.mk
refine ⟨fun f g => ?_, fun f g η μ => ?_⟩
· obtain ⟨c, ⟨t, ht⟩⟩ := h₂ (f.hom ≫ F.map (IsFiltered.leftToMax f.right g.right))
(g.hom ≫ F.map (IsFiltered.rightToMax f.right g.right))
refine ⟨.mk (f.hom ≫ F.map (IsFiltered.leftToMax f.right g.right ≫ t)), ?_, ?_, trivial⟩
· exact StructuredArrow.homMk (IsFiltered.leftToMax _ _ ≫ t) rfl
· exact StructuredArrow.homMk (IsFiltered.rightToMax _ _ ≫ t) (by simpa using ht.symm)
· refine ⟨.mk (f.hom ≫ F.map (η.right ≫ IsFiltered.coeqHom η.right μ.right)),
StructuredArrow.homMk (IsFiltered.coeqHom η.right μ.right) (by simp), ?_⟩
simpa using IsFiltered.coeq_condition _ _
theorem isCofiltered_costructuredArrow_of_isCofiltered_of_exists [IsCofilteredOrEmpty C]
(h₁ : ∀ d, ∃ c, Nonempty (F.obj c ⟶ d)) (h₂ : ∀ {d : D} {c : C} (s s' : F.obj c ⟶ d),
∃ (c' : C) (t : c' ⟶ c), F.map t ≫ s = F.map t ≫ s') (d : D) :
IsCofiltered (CostructuredArrow F d) := by
suffices IsFiltered (CostructuredArrow F d)ᵒᵖ from isCofiltered_of_isFiltered_op _
suffices IsFiltered (StructuredArrow (op d) F.op) from
IsFiltered.of_equivalence (costructuredArrowOpEquivalence _ _).symm
apply isFiltered_structuredArrow_of_isFiltered_of_exists
· intro d
obtain ⟨c, ⟨t⟩⟩ := h₁ d.unop
exact ⟨op c, ⟨Quiver.Hom.op t⟩⟩
· intro d c s s'
obtain ⟨c', t, ht⟩ := h₂ s.unop s'.unop
exact ⟨op c', Quiver.Hom.op t, Quiver.Hom.unop_inj ht⟩
theorem Functor.final_of_exists_of_isFiltered [IsFilteredOrEmpty C]
(h₁ : ∀ d, ∃ c, Nonempty (d ⟶ F.obj c)) (h₂ : ∀ {d : D} {c : C} (s s' : d ⟶ F.obj c),
∃ (c' : C) (t : c ⟶ c'), s ≫ F.map t = s' ≫ F.map t) : Functor.Final F := by
suffices ∀ d, IsFiltered (StructuredArrow d F) from final_of_isFiltered_structuredArrow F
exact isFiltered_structuredArrow_of_isFiltered_of_exists F h₁ h₂
theorem Functor.initial_of_exists_of_isCofiltered [IsCofilteredOrEmpty C]
(h₁ : ∀ d, ∃ c, Nonempty (F.obj c ⟶ d)) (h₂ : ∀ {d : D} {c : C} (s s' : F.obj c ⟶ d),
∃ (c' : C) (t : c' ⟶ c), F.map t ≫ s = F.map t ≫ s') : Functor.Initial F := by
suffices ∀ d, IsCofiltered (CostructuredArrow F d) from
initial_of_isCofiltered_costructuredArrow F
exact isCofiltered_costructuredArrow_of_isCofiltered_of_exists F h₁ h₂
| Mathlib/CategoryTheory/Filtered/Final.lean | 108 | 117 | theorem IsFilteredOrEmpty.of_exists_of_isFiltered_of_fullyFaithful [IsFilteredOrEmpty D] [F.Full]
[F.Faithful] (h : ∀ d, ∃ c, Nonempty (d ⟶ F.obj c)) : IsFilteredOrEmpty C where
cocone_objs c c' := by |
obtain ⟨c₀, ⟨f⟩⟩ := h (IsFiltered.max (F.obj c) (F.obj c'))
exact ⟨c₀, F.preimage (IsFiltered.leftToMax _ _ ≫ f),
F.preimage (IsFiltered.rightToMax _ _ ≫ f), trivial⟩
cocone_maps {c c'} f g := by
obtain ⟨c₀, ⟨f₀⟩⟩ := h (IsFiltered.coeq (F.map f) (F.map g))
refine ⟨_, F.preimage (IsFiltered.coeqHom (F.map f) (F.map g) ≫ f₀), F.map_injective ?_⟩
simp [reassoc_of% (IsFiltered.coeq_condition (F.map f) (F.map g))]
| 0 |
import Mathlib.Probability.Notation
import Mathlib.Probability.Integration
import Mathlib.MeasureTheory.Function.L2Space
#align_import probability.variance from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
open MeasureTheory Filter Finset
noncomputable section
open scoped MeasureTheory ProbabilityTheory ENNReal NNReal
namespace ProbabilityTheory
-- Porting note: this lemma replaces `ENNReal.toReal_bit0`, which does not exist in Lean 4
private lemma coe_two : ENNReal.toReal 2 = (2 : ℝ) := rfl
-- Porting note: Consider if `evariance` or `eVariance` is better. Also,
-- consider `eVariationOn` in `Mathlib.Analysis.BoundedVariation`.
def evariance {Ω : Type*} {_ : MeasurableSpace Ω} (X : Ω → ℝ) (μ : Measure Ω) : ℝ≥0∞ :=
∫⁻ ω, (‖X ω - μ[X]‖₊ : ℝ≥0∞) ^ 2 ∂μ
#align probability_theory.evariance ProbabilityTheory.evariance
def variance {Ω : Type*} {_ : MeasurableSpace Ω} (X : Ω → ℝ) (μ : Measure Ω) : ℝ :=
(evariance X μ).toReal
#align probability_theory.variance ProbabilityTheory.variance
variable {Ω : Type*} {m : MeasurableSpace Ω} {X : Ω → ℝ} {μ : Measure Ω}
| Mathlib/Probability/Variance.lean | 65 | 72 | theorem _root_.MeasureTheory.Memℒp.evariance_lt_top [IsFiniteMeasure μ] (hX : Memℒp X 2 μ) :
evariance X μ < ∞ := by |
have := ENNReal.pow_lt_top (hX.sub <| memℒp_const <| μ[X]).2 2
rw [snorm_eq_lintegral_rpow_nnnorm two_ne_zero ENNReal.two_ne_top, ← ENNReal.rpow_two] at this
simp only [coe_two, Pi.sub_apply, ENNReal.one_toReal, one_div] at this
rw [← ENNReal.rpow_mul, inv_mul_cancel (two_ne_zero : (2 : ℝ) ≠ 0), ENNReal.rpow_one] at this
simp_rw [ENNReal.rpow_two] at this
exact this
| 0 |
import Mathlib.Algebra.Group.Subgroup.Basic
import Mathlib.Algebra.Group.Submonoid.Membership
import Mathlib.Data.Finite.Card
#align_import group_theory.subgroup.finite from "leanprover-community/mathlib"@"f93c11933efbc3c2f0299e47b8ff83e9b539cbf6"
variable {G : Type*} [Group G]
variable {A : Type*} [AddGroup A]
namespace Subgroup
namespace Subgroup
section Normalizer
| Mathlib/Algebra/Group/Subgroup/Finite.lean | 259 | 270 | theorem mem_normalizer_fintype {S : Set G} [Finite S] {x : G} (h : ∀ n, n ∈ S → x * n * x⁻¹ ∈ S) :
x ∈ Subgroup.setNormalizer S := by |
haveI := Classical.propDecidable; cases nonempty_fintype S;
haveI := Set.fintypeImage S fun n => x * n * x⁻¹;
exact fun n =>
⟨h n, fun h₁ =>
have heq : (fun n => x * n * x⁻¹) '' S = S :=
Set.eq_of_subset_of_card_le (fun n ⟨y, hy⟩ => hy.2 ▸ h y hy.1)
(by rw [Set.card_image_of_injective S conj_injective])
have : x * n * x⁻¹ ∈ (fun n => x * n * x⁻¹) '' S := heq.symm ▸ h₁
let ⟨y, hy⟩ := this
conj_injective hy.2 ▸ hy.1⟩
| 0 |
import Mathlib.CategoryTheory.Limits.Preserves.Shapes.BinaryProducts
import Mathlib.CategoryTheory.Limits.Preserves.Shapes.Products
import Mathlib.CategoryTheory.Limits.ConcreteCategory
import Mathlib.CategoryTheory.Limits.Shapes.Types
import Mathlib.CategoryTheory.Limits.Shapes.Multiequalizer
import Mathlib.CategoryTheory.Limits.Shapes.Kernels
universe w v u t r
namespace CategoryTheory.Limits.Concrete
attribute [local instance] ConcreteCategory.instFunLike ConcreteCategory.hasCoeToSort
variable {C : Type u} [Category.{v} C]
section Products
section Multiequalizer
variable [ConcreteCategory.{max w v} C]
| Mathlib/CategoryTheory/Limits/Shapes/ConcreteCategory.lean | 252 | 259 | theorem multiequalizer_ext {I : MulticospanIndex.{w} C} [HasMultiequalizer I]
[PreservesLimit I.multicospan (forget C)] (x y : ↑(multiequalizer I))
(h : ∀ t : I.L, Multiequalizer.ι I t x = Multiequalizer.ι I t y) : x = y := by |
apply Concrete.limit_ext
rintro (a | b)
· apply h
· rw [← limit.w I.multicospan (WalkingMulticospan.Hom.fst b), comp_apply, comp_apply]
simp [h]
| 0 |
import Mathlib.Analysis.Calculus.LineDeriv.Basic
import Mathlib.Analysis.Calculus.FDeriv.Measurable
open MeasureTheory
variable {𝕜 : Type*} [NontriviallyNormedField 𝕜] [LocallyCompactSpace 𝕜]
{E : Type*} [NormedAddCommGroup E] [NormedSpace 𝕜 E] [MeasurableSpace E] [OpensMeasurableSpace E]
{F : Type*} [NormedAddCommGroup F] [NormedSpace 𝕜 F] [CompleteSpace F]
{f : E → F} {v : E}
theorem measurableSet_lineDifferentiableAt (hf : Continuous f) :
MeasurableSet {x : E | LineDifferentiableAt 𝕜 f x v} := by
borelize 𝕜
let g : E → 𝕜 → F := fun x t ↦ f (x + t • v)
have hg : Continuous g.uncurry := by apply hf.comp; continuity
exact measurable_prod_mk_right (measurableSet_of_differentiableAt_with_param 𝕜 hg)
theorem measurable_lineDeriv [MeasurableSpace F] [BorelSpace F]
(hf : Continuous f) : Measurable (fun x ↦ lineDeriv 𝕜 f x v) := by
borelize 𝕜
let g : E → 𝕜 → F := fun x t ↦ f (x + t • v)
have hg : Continuous g.uncurry := by apply hf.comp; continuity
exact (measurable_deriv_with_param hg).comp measurable_prod_mk_right
theorem stronglyMeasurable_lineDeriv [SecondCountableTopologyEither E F] (hf : Continuous f) :
StronglyMeasurable (fun x ↦ lineDeriv 𝕜 f x v) := by
borelize 𝕜
let g : E → 𝕜 → F := fun x t ↦ f (x + t • v)
have hg : Continuous g.uncurry := by apply hf.comp; continuity
exact (stronglyMeasurable_deriv_with_param hg).comp_measurable measurable_prod_mk_right
theorem aemeasurable_lineDeriv [MeasurableSpace F] [BorelSpace F]
(hf : Continuous f) (μ : Measure E) :
AEMeasurable (fun x ↦ lineDeriv 𝕜 f x v) μ :=
(measurable_lineDeriv hf).aemeasurable
theorem aestronglyMeasurable_lineDeriv [SecondCountableTopologyEither E F]
(hf : Continuous f) (μ : Measure E) :
AEStronglyMeasurable (fun x ↦ lineDeriv 𝕜 f x v) μ :=
(stronglyMeasurable_lineDeriv hf).aestronglyMeasurable
variable [SecondCountableTopology E]
| Mathlib/Analysis/Calculus/LineDeriv/Measurable.lean | 72 | 81 | theorem measurableSet_lineDifferentiableAt_uncurry (hf : Continuous f) :
MeasurableSet {p : E × E | LineDifferentiableAt 𝕜 f p.1 p.2} := by |
borelize 𝕜
let g : (E × E) → 𝕜 → F := fun p t ↦ f (p.1 + t • p.2)
have : Continuous g.uncurry :=
hf.comp <| (continuous_fst.comp continuous_fst).add
<| continuous_snd.smul (continuous_snd.comp continuous_fst)
have M_meas : MeasurableSet {q : (E × E) × 𝕜 | DifferentiableAt 𝕜 (g q.1) q.2} :=
measurableSet_of_differentiableAt_with_param 𝕜 this
exact measurable_prod_mk_right M_meas
| 0 |
import Mathlib.Analysis.Complex.AbsMax
import Mathlib.Analysis.Complex.RemovableSingularity
#align_import analysis.complex.schwarz from "leanprover-community/mathlib"@"3f655f5297b030a87d641ad4e825af8d9679eb0b"
open Metric Set Function Filter TopologicalSpace
open scoped Topology
namespace Complex
section Space
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℂ E] {R R₁ R₂ : ℝ} {f : ℂ → E}
{c z z₀ : ℂ}
theorem schwarz_aux {f : ℂ → ℂ} (hd : DifferentiableOn ℂ f (ball c R₁))
(h_maps : MapsTo f (ball c R₁) (ball (f c) R₂)) (hz : z ∈ ball c R₁) :
‖dslope f c z‖ ≤ R₂ / R₁ := by
have hR₁ : 0 < R₁ := nonempty_ball.1 ⟨z, hz⟩
suffices ∀ᶠ r in 𝓝[<] R₁, ‖dslope f c z‖ ≤ R₂ / r by
refine ge_of_tendsto ?_ this
exact (tendsto_const_nhds.div tendsto_id hR₁.ne').mono_left nhdsWithin_le_nhds
rw [mem_ball] at hz
filter_upwards [Ioo_mem_nhdsWithin_Iio ⟨hz, le_rfl⟩] with r hr
have hr₀ : 0 < r := dist_nonneg.trans_lt hr.1
replace hd : DiffContOnCl ℂ (dslope f c) (ball c r) := by
refine DifferentiableOn.diffContOnCl ?_
rw [closure_ball c hr₀.ne']
exact ((differentiableOn_dslope <| ball_mem_nhds _ hR₁).mpr hd).mono
(closedBall_subset_ball hr.2)
refine norm_le_of_forall_mem_frontier_norm_le isBounded_ball hd ?_ ?_
· rw [frontier_ball c hr₀.ne']
intro z hz
have hz' : z ≠ c := ne_of_mem_sphere hz hr₀.ne'
rw [dslope_of_ne _ hz', slope_def_module, norm_smul, norm_inv, mem_sphere_iff_norm.1 hz, ←
div_eq_inv_mul, div_le_div_right hr₀, ← dist_eq_norm]
exact le_of_lt (h_maps (mem_ball.2 (by rw [mem_sphere.1 hz]; exact hr.2)))
· rw [closure_ball c hr₀.ne', mem_closedBall]
exact hr.1.le
#align complex.schwarz_aux Complex.schwarz_aux
| Mathlib/Analysis/Complex/Schwarz.lean | 92 | 108 | theorem norm_dslope_le_div_of_mapsTo_ball (hd : DifferentiableOn ℂ f (ball c R₁))
(h_maps : MapsTo f (ball c R₁) (ball (f c) R₂)) (hz : z ∈ ball c R₁) :
‖dslope f c z‖ ≤ R₂ / R₁ := by |
have hR₁ : 0 < R₁ := nonempty_ball.1 ⟨z, hz⟩
have hR₂ : 0 < R₂ := nonempty_ball.1 ⟨f z, h_maps hz⟩
rcases eq_or_ne (dslope f c z) 0 with hc | hc
· rw [hc, norm_zero]; exact div_nonneg hR₂.le hR₁.le
rcases exists_dual_vector ℂ _ hc with ⟨g, hg, hgf⟩
have hg' : ‖g‖₊ = 1 := NNReal.eq hg
have hg₀ : ‖g‖₊ ≠ 0 := by simpa only [hg'] using one_ne_zero
calc
‖dslope f c z‖ = ‖dslope (g ∘ f) c z‖ := by
rw [g.dslope_comp, hgf, RCLike.norm_ofReal, abs_norm]
exact fun _ => hd.differentiableAt (ball_mem_nhds _ hR₁)
_ ≤ R₂ / R₁ := by
refine schwarz_aux (g.differentiable.comp_differentiableOn hd) (MapsTo.comp ?_ h_maps) hz
simpa only [hg', NNReal.coe_one, one_mul] using g.lipschitz.mapsTo_ball hg₀ (f c) R₂
| 0 |
import Mathlib.Analysis.Normed.Field.Basic
#align_import topology.metric_space.cau_seq_filter from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
universe u v
open Set Filter
open scoped Classical
open Topology
variable {β : Type v}
theorem CauSeq.tendsto_limit [NormedRing β] [hn : IsAbsoluteValue (norm : β → ℝ)]
(f : CauSeq β norm) [CauSeq.IsComplete β norm] : Tendsto f atTop (𝓝 f.lim) :=
tendsto_nhds.mpr
(by
intro s os lfs
suffices ∃ a : ℕ, ∀ b : ℕ, b ≥ a → f b ∈ s by simpa using this
rcases Metric.isOpen_iff.1 os _ lfs with ⟨ε, ⟨hε, hεs⟩⟩
cases' Setoid.symm (CauSeq.equiv_lim f) _ hε with N hN
exists N
intro b hb
apply hεs
dsimp [Metric.ball]
rw [dist_comm, dist_eq_norm]
solve_by_elim)
#align cau_seq.tendsto_limit CauSeq.tendsto_limit
variable [NormedField β]
open Metric
theorem CauchySeq.isCauSeq {f : ℕ → β} (hf : CauchySeq f) : IsCauSeq norm f := by
cases' cauchy_iff.1 hf with hf1 hf2
intro ε hε
rcases hf2 { x | dist x.1 x.2 < ε } (dist_mem_uniformity hε) with ⟨t, ⟨ht, htsub⟩⟩
simp only [mem_map, mem_atTop_sets, ge_iff_le, mem_preimage] at ht; cases' ht with N hN
exists N
intro j hj
rw [← dist_eq_norm]
apply @htsub (f j, f N)
apply Set.mk_mem_prod <;> solve_by_elim [le_refl]
#align cauchy_seq.is_cau_seq CauchySeq.isCauSeq
| Mathlib/Topology/MetricSpace/CauSeqFilter.lean | 67 | 82 | theorem CauSeq.cauchySeq (f : CauSeq β norm) : CauchySeq f := by |
refine cauchy_iff.2 ⟨by infer_instance, fun s hs => ?_⟩
rcases mem_uniformity_dist.1 hs with ⟨ε, ⟨hε, hεs⟩⟩
cases' CauSeq.cauchy₂ f hε with N hN
exists { n | n ≥ N }.image f
simp only [exists_prop, mem_atTop_sets, mem_map, mem_image, ge_iff_le, mem_setOf_eq]
constructor
· exists N
intro b hb
exists b
· rintro ⟨a, b⟩ ⟨⟨a', ⟨ha'1, ha'2⟩⟩, ⟨b', ⟨hb'1, hb'2⟩⟩⟩
dsimp at ha'1 ha'2 hb'1 hb'2
rw [← ha'2, ← hb'2]
apply hεs
rw [dist_eq_norm]
apply hN <;> assumption
| 0 |
import Mathlib.Data.Complex.Basic
import Mathlib.MeasureTheory.Integral.CircleIntegral
#align_import measure_theory.integral.circle_transform from "leanprover-community/mathlib"@"d11893b411025250c8e61ff2f12ccbd7ee35ab15"
open Set MeasureTheory Metric Filter Function
open scoped Interval Real
noncomputable section
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℂ E] (R : ℝ) (z w : ℂ)
namespace Complex
def circleTransform (f : ℂ → E) (θ : ℝ) : E :=
(2 * ↑π * I)⁻¹ • deriv (circleMap z R) θ • (circleMap z R θ - w)⁻¹ • f (circleMap z R θ)
#align complex.circle_transform Complex.circleTransform
def circleTransformDeriv (f : ℂ → E) (θ : ℝ) : E :=
(2 * ↑π * I)⁻¹ • deriv (circleMap z R) θ • ((circleMap z R θ - w) ^ 2)⁻¹ • f (circleMap z R θ)
#align complex.circle_transform_deriv Complex.circleTransformDeriv
theorem circleTransformDeriv_periodic (f : ℂ → E) :
Periodic (circleTransformDeriv R z w f) (2 * π) := by
have := periodic_circleMap
simp_rw [Periodic] at *
intro x
simp_rw [circleTransformDeriv, this]
congr 2
simp [this]
#align complex.circle_transform_deriv_periodic Complex.circleTransformDeriv_periodic
theorem circleTransformDeriv_eq (f : ℂ → E) : circleTransformDeriv R z w f =
fun θ => (circleMap z R θ - w)⁻¹ • circleTransform R z w f θ := by
ext
simp_rw [circleTransformDeriv, circleTransform, ← mul_smul, ← mul_assoc]
ring_nf
rw [inv_pow]
congr
ring
#align complex.circle_transform_deriv_eq Complex.circleTransformDeriv_eq
theorem integral_circleTransform (f : ℂ → E) :
(∫ θ : ℝ in (0)..2 * π, circleTransform R z w f θ) =
(2 * ↑π * I)⁻¹ • ∮ z in C(z, R), (z - w)⁻¹ • f z := by
simp_rw [circleTransform, circleIntegral, deriv_circleMap, circleMap]
simp
#align complex.integral_circle_transform Complex.integral_circleTransform
theorem continuous_circleTransform {R : ℝ} (hR : 0 < R) {f : ℂ → E} {z w : ℂ}
(hf : ContinuousOn f <| sphere z R) (hw : w ∈ ball z R) :
Continuous (circleTransform R z w f) := by
apply_rules [Continuous.smul, continuous_const]
· simp_rw [deriv_circleMap]
apply_rules [Continuous.mul, continuous_circleMap 0 R, continuous_const]
· exact continuous_circleMap_inv hw
· apply ContinuousOn.comp_continuous hf (continuous_circleMap z R)
exact fun _ => (circleMap_mem_sphere _ hR.le) _
#align complex.continuous_circle_transform Complex.continuous_circleTransform
theorem continuous_circleTransformDeriv {R : ℝ} (hR : 0 < R) {f : ℂ → E} {z w : ℂ}
(hf : ContinuousOn f (sphere z R)) (hw : w ∈ ball z R) :
Continuous (circleTransformDeriv R z w f) := by
rw [circleTransformDeriv_eq]
exact (continuous_circleMap_inv hw).smul (continuous_circleTransform hR hf hw)
#align complex.continuous_circle_transform_deriv Complex.continuous_circleTransformDeriv
def circleTransformBoundingFunction (R : ℝ) (z : ℂ) (w : ℂ × ℝ) : ℂ :=
circleTransformDeriv R z w.1 (fun _ => 1) w.2
#align complex.circle_transform_bounding_function Complex.circleTransformBoundingFunction
theorem continuousOn_prod_circle_transform_function {R r : ℝ} (hr : r < R) {z : ℂ} :
ContinuousOn (fun w : ℂ × ℝ => (circleMap z R w.snd - w.fst)⁻¹ ^ 2)
(closedBall z r ×ˢ univ) := by
simp_rw [← one_div]
apply_rules [ContinuousOn.pow, ContinuousOn.div, continuousOn_const]
· exact ((continuous_circleMap z R).comp_continuousOn continuousOn_snd).sub continuousOn_fst
· rintro ⟨a, b⟩ ⟨ha, -⟩
have ha2 : a ∈ ball z R := closedBall_subset_ball hr ha
exact sub_ne_zero.2 (circleMap_ne_mem_ball ha2 b)
#align complex.continuous_on_prod_circle_transform_function Complex.continuousOn_prod_circle_transform_function
theorem continuousOn_abs_circleTransformBoundingFunction {R r : ℝ} (hr : r < R) (z : ℂ) :
ContinuousOn (abs ∘ circleTransformBoundingFunction R z) (closedBall z r ×ˢ univ) := by
have : ContinuousOn (circleTransformBoundingFunction R z) (closedBall z r ×ˢ univ) := by
apply_rules [ContinuousOn.smul, continuousOn_const]
· simp only [deriv_circleMap]
apply_rules [ContinuousOn.mul, (continuous_circleMap 0 R).comp_continuousOn continuousOn_snd,
continuousOn_const]
· simpa only [inv_pow] using continuousOn_prod_circle_transform_function hr
exact this.norm
#align complex.continuous_on_abs_circle_transform_bounding_function Complex.continuousOn_abs_circleTransformBoundingFunction
| Mathlib/MeasureTheory/Integral/CircleTransform.lean | 120 | 129 | theorem abs_circleTransformBoundingFunction_le {R r : ℝ} (hr : r < R) (hr' : 0 ≤ r) (z : ℂ) :
∃ x : closedBall z r ×ˢ [[0, 2 * π]], ∀ y : closedBall z r ×ˢ [[0, 2 * π]],
abs (circleTransformBoundingFunction R z y) ≤ abs (circleTransformBoundingFunction R z x) := by |
have cts := continuousOn_abs_circleTransformBoundingFunction hr z
have comp : IsCompact (closedBall z r ×ˢ [[0, 2 * π]]) := by
apply_rules [IsCompact.prod, ProperSpace.isCompact_closedBall z r, isCompact_uIcc]
have none : (closedBall z r ×ˢ [[0, 2 * π]]).Nonempty :=
(nonempty_closedBall.2 hr').prod nonempty_uIcc
have := IsCompact.exists_isMaxOn comp none (cts.mono <| prod_mono_right (subset_univ _))
simpa [isMaxOn_iff] using this
| 0 |
import Mathlib.Algebra.Field.ULift
import Mathlib.Algebra.MvPolynomial.Cardinal
import Mathlib.Data.Nat.Factorization.PrimePow
import Mathlib.Data.Rat.Denumerable
import Mathlib.FieldTheory.Finite.GaloisField
import Mathlib.Logic.Equiv.TransferInstance
import Mathlib.RingTheory.Localization.Cardinality
import Mathlib.SetTheory.Cardinal.Divisibility
#align_import field_theory.cardinality from "leanprover-community/mathlib"@"0723536a0522d24fc2f159a096fb3304bef77472"
local notation "‖" x "‖" => Fintype.card x
open scoped Cardinal nonZeroDivisors
universe u
theorem Fintype.isPrimePow_card_of_field {α} [Fintype α] [Field α] : IsPrimePow ‖α‖ := by
-- TODO: `Algebra` version of `CharP.exists`, of type `∀ p, Algebra (ZMod p) α`
cases' CharP.exists α with p _
haveI hp := Fact.mk (CharP.char_is_prime α p)
letI : Algebra (ZMod p) α := ZMod.algebra _ _
let b := IsNoetherian.finsetBasis (ZMod p) α
rw [Module.card_fintype b, ZMod.card, isPrimePow_pow_iff]
· exact hp.1.isPrimePow
rw [← FiniteDimensional.finrank_eq_card_basis b]
exact FiniteDimensional.finrank_pos.ne'
#align fintype.is_prime_pow_card_of_field Fintype.isPrimePow_card_of_field
| Mathlib/FieldTheory/Cardinality.lean | 53 | 57 | theorem Fintype.nonempty_field_iff {α} [Fintype α] : Nonempty (Field α) ↔ IsPrimePow ‖α‖ := by |
refine ⟨fun ⟨h⟩ => Fintype.isPrimePow_card_of_field, ?_⟩
rintro ⟨p, n, hp, hn, hα⟩
haveI := Fact.mk hp.nat_prime
exact ⟨(Fintype.equivOfCardEq ((GaloisField.card p n hn.ne').trans hα)).symm.field⟩
| 0 |
import Mathlib.MeasureTheory.Integral.Lebesgue
import Mathlib.Analysis.MeanInequalities
import Mathlib.Analysis.MeanInequalitiesPow
import Mathlib.MeasureTheory.Function.SpecialFunctions.Basic
#align_import measure_theory.integral.mean_inequalities from "leanprover-community/mathlib"@"13bf7613c96a9fd66a81b9020a82cad9a6ea1fcf"
section LIntegral
noncomputable section
open scoped Classical
open NNReal ENNReal MeasureTheory Finset
set_option linter.uppercaseLean3 false
variable {α : Type*} [MeasurableSpace α] {μ : Measure α}
namespace ENNReal
| Mathlib/MeasureTheory/Integral/MeanInequalities.lean | 66 | 79 | theorem lintegral_mul_le_one_of_lintegral_rpow_eq_one {p q : ℝ} (hpq : p.IsConjExponent q)
{f g : α → ℝ≥0∞} (hf : AEMeasurable f μ) (hf_norm : ∫⁻ a, f a ^ p ∂μ = 1)
(hg_norm : ∫⁻ a, g a ^ q ∂μ = 1) : (∫⁻ a, (f * g) a ∂μ) ≤ 1 := by |
calc
(∫⁻ a : α, (f * g) a ∂μ) ≤
∫⁻ a : α, f a ^ p / ENNReal.ofReal p + g a ^ q / ENNReal.ofReal q ∂μ :=
lintegral_mono fun a => young_inequality (f a) (g a) hpq
_ = 1 := by
simp only [div_eq_mul_inv]
rw [lintegral_add_left']
· rw [lintegral_mul_const'' _ (hf.pow_const p), lintegral_mul_const', hf_norm, hg_norm,
one_mul, one_mul, hpq.inv_add_inv_conj_ennreal]
simp [hpq.symm.pos]
· exact (hf.pow_const _).mul_const _
| 0 |
import Mathlib.RingTheory.GradedAlgebra.HomogeneousIdeal
#align_import ring_theory.graded_algebra.radical from "leanprover-community/mathlib"@"f1944b30c97c5eb626e498307dec8b022a05bd0a"
open GradedRing DirectSum SetLike Finset
variable {ι σ A : Type*}
variable [CommRing A]
variable [LinearOrderedCancelAddCommMonoid ι]
variable [SetLike σ A] [AddSubmonoidClass σ A] {𝒜 : ι → σ} [GradedRing 𝒜]
-- Porting note: This proof needs a long time to elaborate
| Mathlib/RingTheory/GradedAlgebra/Radical.lean | 47 | 136 | theorem Ideal.IsHomogeneous.isPrime_of_homogeneous_mem_or_mem {I : Ideal A} (hI : I.IsHomogeneous 𝒜)
(I_ne_top : I ≠ ⊤)
(homogeneous_mem_or_mem :
∀ {x y : A}, Homogeneous 𝒜 x → Homogeneous 𝒜 y → x * y ∈ I → x ∈ I ∨ y ∈ I) :
Ideal.IsPrime I :=
⟨I_ne_top, by
intro x y hxy
by_contra! rid
obtain ⟨rid₁, rid₂⟩ := rid
classical
/-
The idea of the proof is the following :
since `x * y ∈ I` and `I` homogeneous, then `proj i (x * y) ∈ I` for any `i : ι`.
Then consider two sets `{i ∈ x.support | xᵢ ∉ I}` and `{j ∈ y.support | yⱼ ∉ J}`;
let `max₁, max₂` be the maximum of the two sets, then `proj (max₁ + max₂) (x * y) ∈ I`.
Then, `proj max₁ x ∉ I` and `proj max₂ j ∉ I`
but `proj i x ∈ I` for all `max₁ < i` and `proj j y ∈ I` for all `max₂ < j`.
` proj (max₁ + max₂) (x * y)`
`= ∑ {(i, j) ∈ supports | i + j = max₁ + max₂}, xᵢ * yⱼ`
`= proj max₁ x * proj max₂ y`
` + ∑ {(i, j) ∈ supports \ {(max₁, max₂)} | i + j = max₁ + max₂}, xᵢ * yⱼ`.
This is a contradiction, because both `proj (max₁ + max₂) (x * y) ∈ I` and the sum on the
right hand side is in `I` however `proj max₁ x * proj max₂ y` is not in `I`.
-/
set set₁ := (decompose 𝒜 x).support.filter (fun i => proj 𝒜 i x ∉ I) with set₁_eq
set set₂ := (decompose 𝒜 y).support.filter (fun i => proj 𝒜 i y ∉ I) with set₂_eq
have nonempty :
∀ x : A, x ∉ I → ((decompose 𝒜 x).support.filter (fun i => proj 𝒜 i x ∉ I)).Nonempty := by |
intro x hx
rw [filter_nonempty_iff]
contrapose! hx
simp_rw [proj_apply] at hx
rw [← sum_support_decompose 𝒜 x]
exact Ideal.sum_mem _ hx
set max₁ := set₁.max' (nonempty x rid₁)
set max₂ := set₂.max' (nonempty y rid₂)
have mem_max₁ : max₁ ∈ set₁ := max'_mem set₁ (nonempty x rid₁)
have mem_max₂ : max₂ ∈ set₂ := max'_mem set₂ (nonempty y rid₂)
replace hxy : proj 𝒜 (max₁ + max₂) (x * y) ∈ I := hI _ hxy
have mem_I : proj 𝒜 max₁ x * proj 𝒜 max₂ y ∈ I := by
set antidiag :=
((decompose 𝒜 x).support ×ˢ (decompose 𝒜 y).support).filter (fun z : ι × ι =>
z.1 + z.2 = max₁ + max₂) with ha
have mem_antidiag : (max₁, max₂) ∈ antidiag := by
simp only [antidiag, add_sum_erase, mem_filter, mem_product]
exact ⟨⟨mem_of_mem_filter _ mem_max₁, mem_of_mem_filter _ mem_max₂⟩, trivial⟩
have eq_add_sum :=
calc
proj 𝒜 (max₁ + max₂) (x * y) = ∑ ij ∈ antidiag, proj 𝒜 ij.1 x * proj 𝒜 ij.2 y := by
simp_rw [ha, proj_apply, DirectSum.decompose_mul, DirectSum.coe_mul_apply 𝒜]
_ =
proj 𝒜 max₁ x * proj 𝒜 max₂ y +
∑ ij ∈ antidiag.erase (max₁, max₂), proj 𝒜 ij.1 x * proj 𝒜 ij.2 y :=
(add_sum_erase _ _ mem_antidiag).symm
rw [eq_sub_of_add_eq eq_add_sum.symm]
refine Ideal.sub_mem _ hxy (Ideal.sum_mem _ fun z H => ?_)
rcases z with ⟨i, j⟩
simp only [antidiag, mem_erase, Prod.mk.inj_iff, Ne, mem_filter, mem_product] at H
rcases H with ⟨H₁, ⟨H₂, H₃⟩, H₄⟩
have max_lt : max₁ < i ∨ max₂ < j := by
rcases lt_trichotomy max₁ i with (h | rfl | h)
· exact Or.inl h
· refine False.elim (H₁ ⟨rfl, add_left_cancel H₄⟩)
· apply Or.inr
have := add_lt_add_right h j
rw [H₄] at this
exact lt_of_add_lt_add_left this
cases' max_lt with max_lt max_lt
· -- in this case `max₁ < i`, then `xᵢ ∈ I`; for otherwise `i ∈ set₁` then `i ≤ max₁`.
have not_mem : i ∉ set₁ := fun h =>
lt_irrefl _ ((max'_lt_iff set₁ (nonempty x rid₁)).mp max_lt i h)
rw [set₁_eq] at not_mem
simp only [not_and, Classical.not_not, Ne, mem_filter] at not_mem
exact Ideal.mul_mem_right _ I (not_mem H₂)
· -- in this case `max₂ < j`, then `yⱼ ∈ I`; for otherwise `j ∈ set₂`, then `j ≤ max₂`.
have not_mem : j ∉ set₂ := fun h =>
lt_irrefl _ ((max'_lt_iff set₂ (nonempty y rid₂)).mp max_lt j h)
rw [set₂_eq] at not_mem
simp only [not_and, Classical.not_not, Ne, mem_filter] at not_mem
exact Ideal.mul_mem_left I _ (not_mem H₃)
have not_mem_I : proj 𝒜 max₁ x * proj 𝒜 max₂ y ∉ I := by
have neither_mem : proj 𝒜 max₁ x ∉ I ∧ proj 𝒜 max₂ y ∉ I := by
rw [mem_filter] at mem_max₁ mem_max₂
exact ⟨mem_max₁.2, mem_max₂.2⟩
intro _rid
cases' homogeneous_mem_or_mem ⟨max₁, SetLike.coe_mem _⟩ ⟨max₂, SetLike.coe_mem _⟩ mem_I
with h h
· apply neither_mem.1 h
· apply neither_mem.2 h
exact not_mem_I mem_I⟩
| 0 |
import Mathlib.Analysis.Calculus.Deriv.Inv
import Mathlib.Analysis.NormedSpace.BallAction
import Mathlib.Analysis.SpecialFunctions.ExpDeriv
import Mathlib.Analysis.InnerProductSpace.Calculus
import Mathlib.Analysis.InnerProductSpace.PiL2
import Mathlib.Geometry.Manifold.Algebra.LieGroup
import Mathlib.Geometry.Manifold.Instances.Real
import Mathlib.Geometry.Manifold.MFDeriv.Basic
#align_import geometry.manifold.instances.sphere from "leanprover-community/mathlib"@"0dc4079202c28226b2841a51eb6d3cc2135bb80f"
variable {E : Type*} [NormedAddCommGroup E] [InnerProductSpace ℝ E]
noncomputable section
open Metric FiniteDimensional Function
open scoped Manifold
section StereographicProjection
variable (v : E)
def stereoToFun (x : E) : (ℝ ∙ v)ᗮ :=
(2 / ((1 : ℝ) - innerSL ℝ v x)) • orthogonalProjection (ℝ ∙ v)ᗮ x
#align stereo_to_fun stereoToFun
variable {v}
@[simp]
theorem stereoToFun_apply (x : E) :
stereoToFun v x = (2 / ((1 : ℝ) - innerSL ℝ v x)) • orthogonalProjection (ℝ ∙ v)ᗮ x :=
rfl
#align stereo_to_fun_apply stereoToFun_apply
theorem contDiffOn_stereoToFun :
ContDiffOn ℝ ⊤ (stereoToFun v) {x : E | innerSL _ v x ≠ (1 : ℝ)} := by
refine ContDiffOn.smul ?_ (orthogonalProjection (ℝ ∙ v)ᗮ).contDiff.contDiffOn
refine contDiff_const.contDiffOn.div ?_ ?_
· exact (contDiff_const.sub (innerSL ℝ v).contDiff).contDiffOn
· intro x h h'
exact h (sub_eq_zero.mp h').symm
#align cont_diff_on_stereo_to_fun contDiffOn_stereoToFun
theorem continuousOn_stereoToFun :
ContinuousOn (stereoToFun v) {x : E | innerSL _ v x ≠ (1 : ℝ)} :=
contDiffOn_stereoToFun.continuousOn
#align continuous_on_stereo_to_fun continuousOn_stereoToFun
variable (v)
def stereoInvFunAux (w : E) : E :=
(‖w‖ ^ 2 + 4)⁻¹ • ((4 : ℝ) • w + (‖w‖ ^ 2 - 4) • v)
#align stereo_inv_fun_aux stereoInvFunAux
variable {v}
@[simp]
theorem stereoInvFunAux_apply (w : E) :
stereoInvFunAux v w = (‖w‖ ^ 2 + 4)⁻¹ • ((4 : ℝ) • w + (‖w‖ ^ 2 - 4) • v) :=
rfl
#align stereo_inv_fun_aux_apply stereoInvFunAux_apply
theorem stereoInvFunAux_mem (hv : ‖v‖ = 1) {w : E} (hw : w ∈ (ℝ ∙ v)ᗮ) :
stereoInvFunAux v w ∈ sphere (0 : E) 1 := by
have h₁ : (0 : ℝ) < ‖w‖ ^ 2 + 4 := by positivity
suffices ‖(4 : ℝ) • w + (‖w‖ ^ 2 - 4) • v‖ = ‖w‖ ^ 2 + 4 by
simp only [mem_sphere_zero_iff_norm, norm_smul, Real.norm_eq_abs, abs_inv, this,
abs_of_pos h₁, stereoInvFunAux_apply, inv_mul_cancel h₁.ne']
suffices ‖(4 : ℝ) • w + (‖w‖ ^ 2 - 4) • v‖ ^ 2 = (‖w‖ ^ 2 + 4) ^ 2 by
simpa [sq_eq_sq_iff_abs_eq_abs, abs_of_pos h₁] using this
rw [Submodule.mem_orthogonal_singleton_iff_inner_left] at hw
simp [norm_add_sq_real, norm_smul, inner_smul_left, inner_smul_right, hw, mul_pow,
Real.norm_eq_abs, hv]
ring
#align stereo_inv_fun_aux_mem stereoInvFunAux_mem
theorem hasFDerivAt_stereoInvFunAux (v : E) :
HasFDerivAt (stereoInvFunAux v) (ContinuousLinearMap.id ℝ E) 0 := by
have h₀ : HasFDerivAt (fun w : E => ‖w‖ ^ 2) (0 : E →L[ℝ] ℝ) 0 := by
convert (hasStrictFDerivAt_norm_sq (0 : E)).hasFDerivAt
simp
have h₁ : HasFDerivAt (fun w : E => (‖w‖ ^ 2 + 4)⁻¹) (0 : E →L[ℝ] ℝ) 0 := by
convert (hasFDerivAt_inv _).comp _ (h₀.add (hasFDerivAt_const 4 0)) <;> simp
have h₂ : HasFDerivAt (fun w => (4 : ℝ) • w + (‖w‖ ^ 2 - 4) • v)
((4 : ℝ) • ContinuousLinearMap.id ℝ E) 0 := by
convert ((hasFDerivAt_const (4 : ℝ) 0).smul (hasFDerivAt_id 0)).add
((h₀.sub (hasFDerivAt_const (4 : ℝ) 0)).smul (hasFDerivAt_const v 0)) using 1
ext w
simp
convert h₁.smul h₂ using 1
ext w
simp
#align has_fderiv_at_stereo_inv_fun_aux hasFDerivAt_stereoInvFunAux
theorem hasFDerivAt_stereoInvFunAux_comp_coe (v : E) :
HasFDerivAt (stereoInvFunAux v ∘ ((↑) : (ℝ ∙ v)ᗮ → E)) (ℝ ∙ v)ᗮ.subtypeL 0 := by
have : HasFDerivAt (stereoInvFunAux v) (ContinuousLinearMap.id ℝ E) ((ℝ ∙ v)ᗮ.subtypeL 0) :=
hasFDerivAt_stereoInvFunAux v
convert this.comp (0 : (ℝ ∙ v)ᗮ) (by apply ContinuousLinearMap.hasFDerivAt)
#align has_fderiv_at_stereo_inv_fun_aux_comp_coe hasFDerivAt_stereoInvFunAux_comp_coe
| Mathlib/Geometry/Manifold/Instances/Sphere.lean | 170 | 179 | theorem contDiff_stereoInvFunAux : ContDiff ℝ ⊤ (stereoInvFunAux v) := by |
have h₀ : ContDiff ℝ ⊤ fun w : E => ‖w‖ ^ 2 := contDiff_norm_sq ℝ
have h₁ : ContDiff ℝ ⊤ fun w : E => (‖w‖ ^ 2 + 4)⁻¹ := by
refine (h₀.add contDiff_const).inv ?_
intro x
nlinarith
have h₂ : ContDiff ℝ ⊤ fun w => (4 : ℝ) • w + (‖w‖ ^ 2 - 4) • v := by
refine (contDiff_const.smul contDiff_id).add ?_
exact (h₀.sub contDiff_const).smul contDiff_const
exact h₁.smul h₂
| 0 |
import Mathlib.Geometry.RingedSpace.PresheafedSpace
import Mathlib.CategoryTheory.Limits.Final
import Mathlib.Topology.Sheaves.Stalks
#align_import algebraic_geometry.stalks from "leanprover-community/mathlib"@"d39590fc8728fbf6743249802486f8c91ffe07bc"
noncomputable section
universe v u v' u'
open Opposite CategoryTheory CategoryTheory.Category CategoryTheory.Functor CategoryTheory.Limits
AlgebraicGeometry TopologicalSpace
variable {C : Type u} [Category.{v} C] [HasColimits C]
-- Porting note: no tidy tactic
-- attribute [local tidy] tactic.auto_cases_opens
-- this could be replaced by
-- attribute [local aesop safe cases (rule_sets := [CategoryTheory])] Opens
-- but it doesn't appear to be needed here.
open TopCat.Presheaf
namespace AlgebraicGeometry.PresheafedSpace
abbrev stalk (X : PresheafedSpace C) (x : X) : C :=
X.presheaf.stalk x
set_option linter.uppercaseLean3 false in
#align algebraic_geometry.PresheafedSpace.stalk AlgebraicGeometry.PresheafedSpace.stalk
def stalkMap {X Y : PresheafedSpace.{_, _, v} C} (α : X ⟶ Y) (x : X) :
Y.stalk (α.base x) ⟶ X.stalk x :=
(stalkFunctor C (α.base x)).map α.c ≫ X.presheaf.stalkPushforward C α.base x
set_option linter.uppercaseLean3 false in
#align algebraic_geometry.PresheafedSpace.stalk_map AlgebraicGeometry.PresheafedSpace.stalkMap
@[elementwise, reassoc]
| Mathlib/Geometry/RingedSpace/Stalks.lean | 56 | 59 | theorem stalkMap_germ {X Y : PresheafedSpace.{_, _, v} C} (α : X ⟶ Y) (U : Opens Y)
(x : (Opens.map α.base).obj U) :
Y.presheaf.germ ⟨α.base x.1, x.2⟩ ≫ stalkMap α ↑x = α.c.app (op U) ≫ X.presheaf.germ x := by |
rw [stalkMap, stalkFunctor_map_germ_assoc, stalkPushforward_germ]
| 0 |
import Mathlib.Combinatorics.SetFamily.Shadow
#align_import combinatorics.set_family.compression.uv from "leanprover-community/mathlib"@"6f8ab7de1c4b78a68ab8cf7dd83d549eb78a68a1"
open Finset
variable {α : Type*}
theorem sup_sdiff_injOn [GeneralizedBooleanAlgebra α] (u v : α) :
{ x | Disjoint u x ∧ v ≤ x }.InjOn fun x => (x ⊔ u) \ v := by
rintro a ha b hb hab
have h : ((a ⊔ u) \ v) \ u ⊔ v = ((b ⊔ u) \ v) \ u ⊔ v := by
dsimp at hab
rw [hab]
rwa [sdiff_sdiff_comm, ha.1.symm.sup_sdiff_cancel_right, sdiff_sdiff_comm,
hb.1.symm.sup_sdiff_cancel_right, sdiff_sup_cancel ha.2, sdiff_sup_cancel hb.2] at h
#align sup_sdiff_inj_on sup_sdiff_injOn
-- The namespace is here to distinguish from other compressions.
namespace UV
section GeneralizedBooleanAlgebra
variable [GeneralizedBooleanAlgebra α] [DecidableRel (@Disjoint α _ _)]
[DecidableRel ((· ≤ ·) : α → α → Prop)] {s : Finset α} {u v a b : α}
def compress (u v a : α) : α :=
if Disjoint u a ∧ v ≤ a then (a ⊔ u) \ v else a
#align uv.compress UV.compress
theorem compress_of_disjoint_of_le (hua : Disjoint u a) (hva : v ≤ a) :
compress u v a = (a ⊔ u) \ v :=
if_pos ⟨hua, hva⟩
#align uv.compress_of_disjoint_of_le UV.compress_of_disjoint_of_le
theorem compress_of_disjoint_of_le' (hva : Disjoint v a) (hua : u ≤ a) :
compress u v ((a ⊔ v) \ u) = a := by
rw [compress_of_disjoint_of_le disjoint_sdiff_self_right
(le_sdiff.2 ⟨(le_sup_right : v ≤ a ⊔ v), hva.mono_right hua⟩),
sdiff_sup_cancel (le_sup_of_le_left hua), hva.symm.sup_sdiff_cancel_right]
#align uv.compress_of_disjoint_of_le' UV.compress_of_disjoint_of_le'
@[simp]
theorem compress_self (u a : α) : compress u u a = a := by
unfold compress
split_ifs with h
· exact h.1.symm.sup_sdiff_cancel_right
· rfl
#align uv.compress_self UV.compress_self
@[simp]
theorem compress_sdiff_sdiff (a b : α) : compress (a \ b) (b \ a) b = a := by
refine (compress_of_disjoint_of_le disjoint_sdiff_self_left sdiff_le).trans ?_
rw [sup_sdiff_self_right, sup_sdiff, disjoint_sdiff_self_right.sdiff_eq_left, sup_eq_right]
exact sdiff_sdiff_le
#align uv.compress_sdiff_sdiff UV.compress_sdiff_sdiff
@[simp]
theorem compress_idem (u v a : α) : compress u v (compress u v a) = compress u v a := by
unfold compress
split_ifs with h h'
· rw [le_sdiff_iff.1 h'.2, sdiff_bot, sdiff_bot, sup_assoc, sup_idem]
· rfl
· rfl
#align uv.compress_idem UV.compress_idem
variable [DecidableEq α]
def compression (u v : α) (s : Finset α) :=
(s.filter (compress u v · ∈ s)) ∪ (s.image <| compress u v).filter (· ∉ s)
#align uv.compression UV.compression
@[inherit_doc]
scoped[FinsetFamily] notation "𝓒 " => UV.compression
open scoped FinsetFamily
def IsCompressed (u v : α) (s : Finset α) :=
𝓒 u v s = s
#align uv.is_compressed UV.IsCompressed
| Mathlib/Combinatorics/SetFamily/Compression/UV.lean | 142 | 151 | theorem compress_injOn : Set.InjOn (compress u v) ↑(s.filter (compress u v · ∉ s)) := by |
intro a ha b hb hab
rw [mem_coe, mem_filter] at ha hb
rw [compress] at ha hab
split_ifs at ha hab with has
· rw [compress] at hb hab
split_ifs at hb hab with hbs
· exact sup_sdiff_injOn u v has hbs hab
· exact (hb.2 hb.1).elim
· exact (ha.2 ha.1).elim
| 0 |
import Mathlib.Algebra.Order.Sub.Defs
import Mathlib.Data.Finset.Basic
import Mathlib.Order.Interval.Finset.Defs
open Function
namespace Finset
class HasAntidiagonal (A : Type*) [AddMonoid A] where
antidiagonal : A → Finset (A × A)
mem_antidiagonal {n} {a} : a ∈ antidiagonal n ↔ a.fst + a.snd = n
export HasAntidiagonal (antidiagonal mem_antidiagonal)
attribute [simp] mem_antidiagonal
variable {A : Type*}
instance [AddMonoid A] : Subsingleton (HasAntidiagonal A) :=
⟨by
rintro ⟨a, ha⟩ ⟨b, hb⟩
congr with n xy
rw [ha, hb]⟩
-- The goal of this lemma is to allow to rewrite antidiagonal
-- when the decidability instances obsucate Lean
lemma hasAntidiagonal_congr (A : Type*) [AddMonoid A]
[H1 : HasAntidiagonal A] [H2 : HasAntidiagonal A] :
H1.antidiagonal = H2.antidiagonal := by congr!; apply Subsingleton.elim
theorem swap_mem_antidiagonal [AddCommMonoid A] [HasAntidiagonal A] {n : A} {xy : A × A}:
xy.swap ∈ antidiagonal n ↔ xy ∈ antidiagonal n := by
simp [add_comm]
@[simp] theorem map_prodComm_antidiagonal [AddCommMonoid A] [HasAntidiagonal A] {n : A} :
(antidiagonal n).map (Equiv.prodComm A A) = antidiagonal n :=
Finset.ext fun ⟨a, b⟩ => by simp [add_comm]
@[simp] theorem map_swap_antidiagonal [AddCommMonoid A] [HasAntidiagonal A] {n : A} :
(antidiagonal n).map ⟨Prod.swap, Prod.swap_injective⟩ = antidiagonal n :=
map_prodComm_antidiagonal
#align finset.nat.map_swap_antidiagonal Finset.map_swap_antidiagonal
section OrderedSub
variable [CanonicallyOrderedAddCommMonoid A] [Sub A] [OrderedSub A]
variable [ContravariantClass A A (· + ·) (· ≤ ·)]
variable [HasAntidiagonal A]
theorem filter_fst_eq_antidiagonal (n m : A) [DecidablePred (· = m)] [Decidable (m ≤ n)] :
filter (fun x : A × A ↦ x.fst = m) (antidiagonal n) = if m ≤ n then {(m, n - m)} else ∅ := by
ext ⟨a, b⟩
suffices a = m → (a + b = n ↔ m ≤ n ∧ b = n - m) by
rw [mem_filter, mem_antidiagonal, apply_ite (fun n ↦ (a, b) ∈ n), mem_singleton,
Prod.mk.inj_iff, ite_prop_iff_or]
simpa [ ← and_assoc, @and_right_comm _ (a = _), and_congr_left_iff]
rintro rfl
constructor
· rintro rfl
exact ⟨le_add_right le_rfl, (add_tsub_cancel_left _ _).symm⟩
· rintro ⟨h, rfl⟩
exact add_tsub_cancel_of_le h
#align finset.nat.filter_fst_eq_antidiagonal Finset.filter_fst_eq_antidiagonal
| Mathlib/Data/Finset/Antidiagonal.lean | 169 | 174 | theorem filter_snd_eq_antidiagonal (n m : A) [DecidablePred (· = m)] [Decidable (m ≤ n)] :
filter (fun x : A × A ↦ x.snd = m) (antidiagonal n) = if m ≤ n then {(n - m, m)} else ∅ := by |
have : (fun x : A × A ↦ (x.snd = m)) ∘ Prod.swap = fun x : A × A ↦ x.fst = m := by
ext; simp
rw [← map_swap_antidiagonal, filter_map]
simp [this, filter_fst_eq_antidiagonal, apply_ite (Finset.map _)]
| 0 |
import Mathlib.Combinatorics.SimpleGraph.Connectivity
import Mathlib.Data.Nat.Lattice
#align_import combinatorics.simple_graph.metric from "leanprover-community/mathlib"@"352ecfe114946c903338006dd3287cb5a9955ff2"
namespace SimpleGraph
variable {V : Type*} (G : SimpleGraph V)
noncomputable def dist (u v : V) : ℕ :=
sInf (Set.range (Walk.length : G.Walk u v → ℕ))
#align simple_graph.dist SimpleGraph.dist
variable {G}
protected theorem Reachable.exists_walk_of_dist {u v : V} (hr : G.Reachable u v) :
∃ p : G.Walk u v, p.length = G.dist u v :=
Nat.sInf_mem (Set.range_nonempty_iff_nonempty.mpr hr)
#align simple_graph.reachable.exists_walk_of_dist SimpleGraph.Reachable.exists_walk_of_dist
protected theorem Connected.exists_walk_of_dist (hconn : G.Connected) (u v : V) :
∃ p : G.Walk u v, p.length = G.dist u v :=
(hconn u v).exists_walk_of_dist
#align simple_graph.connected.exists_walk_of_dist SimpleGraph.Connected.exists_walk_of_dist
theorem dist_le {u v : V} (p : G.Walk u v) : G.dist u v ≤ p.length :=
Nat.sInf_le ⟨p, rfl⟩
#align simple_graph.dist_le SimpleGraph.dist_le
@[simp]
theorem dist_eq_zero_iff_eq_or_not_reachable {u v : V} :
G.dist u v = 0 ↔ u = v ∨ ¬G.Reachable u v := by simp [dist, Nat.sInf_eq_zero, Reachable]
#align simple_graph.dist_eq_zero_iff_eq_or_not_reachable SimpleGraph.dist_eq_zero_iff_eq_or_not_reachable
theorem dist_self {v : V} : dist G v v = 0 := by simp
#align simple_graph.dist_self SimpleGraph.dist_self
protected theorem Reachable.dist_eq_zero_iff {u v : V} (hr : G.Reachable u v) :
G.dist u v = 0 ↔ u = v := by simp [hr]
#align simple_graph.reachable.dist_eq_zero_iff SimpleGraph.Reachable.dist_eq_zero_iff
protected theorem Reachable.pos_dist_of_ne {u v : V} (h : G.Reachable u v) (hne : u ≠ v) :
0 < G.dist u v :=
Nat.pos_of_ne_zero (by simp [h, hne])
#align simple_graph.reachable.pos_dist_of_ne SimpleGraph.Reachable.pos_dist_of_ne
protected theorem Connected.dist_eq_zero_iff (hconn : G.Connected) {u v : V} :
G.dist u v = 0 ↔ u = v := by simp [hconn u v]
#align simple_graph.connected.dist_eq_zero_iff SimpleGraph.Connected.dist_eq_zero_iff
protected theorem Connected.pos_dist_of_ne {u v : V} (hconn : G.Connected) (hne : u ≠ v) :
0 < G.dist u v :=
Nat.pos_of_ne_zero (by intro h; exact False.elim (hne (hconn.dist_eq_zero_iff.mp h)))
#align simple_graph.connected.pos_dist_of_ne SimpleGraph.Connected.pos_dist_of_ne
theorem dist_eq_zero_of_not_reachable {u v : V} (h : ¬G.Reachable u v) : G.dist u v = 0 := by
simp [h]
#align simple_graph.dist_eq_zero_of_not_reachable SimpleGraph.dist_eq_zero_of_not_reachable
theorem nonempty_of_pos_dist {u v : V} (h : 0 < G.dist u v) :
(Set.univ : Set (G.Walk u v)).Nonempty := by
simpa [Set.range_nonempty_iff_nonempty, Set.nonempty_iff_univ_nonempty] using
Nat.nonempty_of_pos_sInf h
#align simple_graph.nonempty_of_pos_dist SimpleGraph.nonempty_of_pos_dist
protected theorem Connected.dist_triangle (hconn : G.Connected) {u v w : V} :
G.dist u w ≤ G.dist u v + G.dist v w := by
obtain ⟨p, hp⟩ := hconn.exists_walk_of_dist u v
obtain ⟨q, hq⟩ := hconn.exists_walk_of_dist v w
rw [← hp, ← hq, ← Walk.length_append]
apply dist_le
#align simple_graph.connected.dist_triangle SimpleGraph.Connected.dist_triangle
private theorem dist_comm_aux {u v : V} (h : G.Reachable u v) : G.dist u v ≤ G.dist v u := by
obtain ⟨p, hp⟩ := h.symm.exists_walk_of_dist
rw [← hp, ← Walk.length_reverse]
apply dist_le
theorem dist_comm {u v : V} : G.dist u v = G.dist v u := by
by_cases h : G.Reachable u v
· apply le_antisymm (dist_comm_aux h) (dist_comm_aux h.symm)
· have h' : ¬G.Reachable v u := fun h' => absurd h'.symm h
simp [h, h', dist_eq_zero_of_not_reachable]
#align simple_graph.dist_comm SimpleGraph.dist_comm
lemma dist_ne_zero_iff_ne_and_reachable {u v : V} : G.dist u v ≠ 0 ↔ u ≠ v ∧ G.Reachable u v := by
rw [ne_eq, dist_eq_zero_iff_eq_or_not_reachable.not]
push_neg; rfl
lemma Reachable.of_dist_ne_zero {u v : V} (h : G.dist u v ≠ 0) : G.Reachable u v :=
(dist_ne_zero_iff_ne_and_reachable.mp h).2
lemma exists_walk_of_dist_ne_zero {u v : V} (h : G.dist u v ≠ 0) :
∃ p : G.Walk u v, p.length = G.dist u v :=
(Reachable.of_dist_ne_zero h).exists_walk_of_dist
theorem dist_eq_one_iff_adj {u v : V} : G.dist u v = 1 ↔ G.Adj u v := by
refine ⟨fun h ↦ ?_, fun h ↦ ?_⟩
· let ⟨w, hw⟩ := exists_walk_of_dist_ne_zero <| ne_zero_of_eq_one h
exact w.adj_of_length_eq_one <| h ▸ hw
· have : h.toWalk.length = 1 := Walk.length_cons _ _
exact ge_antisymm (h.reachable.pos_dist_of_ne h.ne) (this ▸ dist_le _)
| Mathlib/Combinatorics/SimpleGraph/Metric.lean | 144 | 153 | theorem Walk.isPath_of_length_eq_dist {u v : V} (p : G.Walk u v) (hp : p.length = G.dist u v) :
p.IsPath := by |
classical
have : p.bypass = p := by
apply Walk.bypass_eq_self_of_length_le
calc p.length
_ = G.dist u v := hp
_ ≤ p.bypass.length := dist_le p.bypass
rw [← this]
apply Walk.bypass_isPath
| 0 |
import Mathlib.Algebra.Quaternion
import Mathlib.Tactic.Ring
#align_import algebra.quaternion_basis from "leanprover-community/mathlib"@"3aa5b8a9ed7a7cabd36e6e1d022c9858ab8a8c2d"
open Quaternion
namespace QuaternionAlgebra
structure Basis {R : Type*} (A : Type*) [CommRing R] [Ring A] [Algebra R A] (c₁ c₂ : R) where
(i j k : A)
i_mul_i : i * i = c₁ • (1 : A)
j_mul_j : j * j = c₂ • (1 : A)
i_mul_j : i * j = k
j_mul_i : j * i = -k
#align quaternion_algebra.basis QuaternionAlgebra.Basis
variable {R : Type*} {A B : Type*} [CommRing R] [Ring A] [Ring B] [Algebra R A] [Algebra R B]
variable {c₁ c₂ : R}
namespace Basis
@[ext]
protected theorem ext ⦃q₁ q₂ : Basis A c₁ c₂⦄ (hi : q₁.i = q₂.i) (hj : q₁.j = q₂.j) : q₁ = q₂ := by
cases q₁; rename_i q₁_i_mul_j _
cases q₂; rename_i q₂_i_mul_j _
congr
rw [← q₁_i_mul_j, ← q₂_i_mul_j]
congr
#align quaternion_algebra.basis.ext QuaternionAlgebra.Basis.ext
variable (R)
@[simps i j k]
protected def self : Basis ℍ[R,c₁,c₂] c₁ c₂ where
i := ⟨0, 1, 0, 0⟩
i_mul_i := by ext <;> simp
j := ⟨0, 0, 1, 0⟩
j_mul_j := by ext <;> simp
k := ⟨0, 0, 0, 1⟩
i_mul_j := by ext <;> simp
j_mul_i := by ext <;> simp
#align quaternion_algebra.basis.self QuaternionAlgebra.Basis.self
variable {R}
instance : Inhabited (Basis ℍ[R,c₁,c₂] c₁ c₂) :=
⟨Basis.self R⟩
variable (q : Basis A c₁ c₂)
attribute [simp] i_mul_i j_mul_j i_mul_j j_mul_i
@[simp]
theorem i_mul_k : q.i * q.k = c₁ • q.j := by
rw [← i_mul_j, ← mul_assoc, i_mul_i, smul_mul_assoc, one_mul]
#align quaternion_algebra.basis.i_mul_k QuaternionAlgebra.Basis.i_mul_k
@[simp]
theorem k_mul_i : q.k * q.i = -c₁ • q.j := by
rw [← i_mul_j, mul_assoc, j_mul_i, mul_neg, i_mul_k, neg_smul]
#align quaternion_algebra.basis.k_mul_i QuaternionAlgebra.Basis.k_mul_i
@[simp]
theorem k_mul_j : q.k * q.j = c₂ • q.i := by
rw [← i_mul_j, mul_assoc, j_mul_j, mul_smul_comm, mul_one]
#align quaternion_algebra.basis.k_mul_j QuaternionAlgebra.Basis.k_mul_j
@[simp]
theorem j_mul_k : q.j * q.k = -c₂ • q.i := by
rw [← i_mul_j, ← mul_assoc, j_mul_i, neg_mul, k_mul_j, neg_smul]
#align quaternion_algebra.basis.j_mul_k QuaternionAlgebra.Basis.j_mul_k
@[simp]
theorem k_mul_k : q.k * q.k = -((c₁ * c₂) • (1 : A)) := by
rw [← i_mul_j, mul_assoc, ← mul_assoc q.j _ _, j_mul_i, ← i_mul_j, ← mul_assoc, mul_neg, ←
mul_assoc, i_mul_i, smul_mul_assoc, one_mul, neg_mul, smul_mul_assoc, j_mul_j, smul_smul]
#align quaternion_algebra.basis.k_mul_k QuaternionAlgebra.Basis.k_mul_k
def lift (x : ℍ[R,c₁,c₂]) : A :=
algebraMap R _ x.re + x.imI • q.i + x.imJ • q.j + x.imK • q.k
#align quaternion_algebra.basis.lift QuaternionAlgebra.Basis.lift
theorem lift_zero : q.lift (0 : ℍ[R,c₁,c₂]) = 0 := by simp [lift]
#align quaternion_algebra.basis.lift_zero QuaternionAlgebra.Basis.lift_zero
theorem lift_one : q.lift (1 : ℍ[R,c₁,c₂]) = 1 := by simp [lift]
#align quaternion_algebra.basis.lift_one QuaternionAlgebra.Basis.lift_one
| Mathlib/Algebra/QuaternionBasis.lean | 120 | 122 | theorem lift_add (x y : ℍ[R,c₁,c₂]) : q.lift (x + y) = q.lift x + q.lift y := by |
simp only [lift, add_re, map_add, add_imI, add_smul, add_imJ, add_imK]
abel
| 0 |
import Mathlib.Topology.Order.ProjIcc
import Mathlib.Topology.CompactOpen
import Mathlib.Topology.UnitInterval
#align_import topology.path_connected from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
noncomputable section
open scoped Classical
open Topology Filter unitInterval Set Function
variable {X Y : Type*} [TopologicalSpace X] [TopologicalSpace Y] {x y z : X} {ι : Type*}
-- porting note (#5171): removed @[nolint has_nonempty_instance]
structure Path (x y : X) extends C(I, X) where
source' : toFun 0 = x
target' : toFun 1 = y
#align path Path
instance Path.funLike : FunLike (Path x y) I X where
coe := fun γ ↦ ⇑γ.toContinuousMap
coe_injective' := fun γ₁ γ₂ h => by
simp only [DFunLike.coe_fn_eq] at h
cases γ₁; cases γ₂; congr
-- Porting note (#10754): added this instance so that we can use `FunLike.coe` for `CoeFun`
-- this also fixed very strange `simp` timeout issues
instance Path.continuousMapClass : ContinuousMapClass (Path x y) I X where
map_continuous := fun γ => show Continuous γ.toContinuousMap by continuity
-- Porting note: not necessary in light of the instance above
@[ext]
protected theorem Path.ext : ∀ {γ₁ γ₂ : Path x y}, (γ₁ : I → X) = γ₂ → γ₁ = γ₂ := by
rintro ⟨⟨x, h11⟩, h12, h13⟩ ⟨⟨x, h21⟩, h22, h23⟩ rfl
rfl
#align path.ext Path.ext
namespace Path
@[simp]
theorem coe_mk_mk (f : I → X) (h₁) (h₂ : f 0 = x) (h₃ : f 1 = y) :
⇑(mk ⟨f, h₁⟩ h₂ h₃ : Path x y) = f :=
rfl
#align path.coe_mk Path.coe_mk_mk
-- Porting note: the name `Path.coe_mk` better refers to a new lemma below
variable (γ : Path x y)
@[continuity]
protected theorem continuous : Continuous γ :=
γ.continuous_toFun
#align path.continuous Path.continuous
@[simp]
protected theorem source : γ 0 = x :=
γ.source'
#align path.source Path.source
@[simp]
protected theorem target : γ 1 = y :=
γ.target'
#align path.target Path.target
def simps.apply : I → X :=
γ
#align path.simps.apply Path.simps.apply
initialize_simps_projections Path (toFun → simps.apply, -toContinuousMap)
@[simp]
theorem coe_toContinuousMap : ⇑γ.toContinuousMap = γ :=
rfl
#align path.coe_to_continuous_map Path.coe_toContinuousMap
-- Porting note: this is needed because of the `Path.continuousMapClass` instance
@[simp]
theorem coe_mk : ⇑(γ : C(I, X)) = γ :=
rfl
instance hasUncurryPath {X α : Type*} [TopologicalSpace X] {x y : α → X} :
HasUncurry (∀ a : α, Path (x a) (y a)) (α × I) X :=
⟨fun φ p => φ p.1 p.2⟩
#align path.has_uncurry_path Path.hasUncurryPath
@[refl, simps]
def refl (x : X) : Path x x where
toFun _t := x
continuous_toFun := continuous_const
source' := rfl
target' := rfl
#align path.refl Path.refl
@[simp]
theorem refl_range {a : X} : range (Path.refl a) = {a} := by simp [Path.refl, CoeFun.coe]
#align path.refl_range Path.refl_range
@[symm, simps]
def symm (γ : Path x y) : Path y x where
toFun := γ ∘ σ
continuous_toFun := by continuity
source' := by simpa [-Path.target] using γ.target
target' := by simpa [-Path.source] using γ.source
#align path.symm Path.symm
@[simp]
| Mathlib/Topology/Connected/PathConnected.lean | 178 | 181 | theorem symm_symm (γ : Path x y) : γ.symm.symm = γ := by |
ext t
show γ (σ (σ t)) = γ t
rw [unitInterval.symm_symm]
| 0 |
import Mathlib.GroupTheory.Sylow
import Mathlib.GroupTheory.Transfer
#align_import group_theory.schur_zassenhaus from "leanprover-community/mathlib"@"d57133e49cf06508700ef69030cd099917e0f0de"
namespace Subgroup
section SchurZassenhausAbelian
open MulOpposite MulAction Subgroup.leftTransversals MemLeftTransversals
variable {G : Type*} [Group G] (H : Subgroup G) [IsCommutative H] [FiniteIndex H]
(α β : leftTransversals (H : Set G))
def QuotientDiff :=
Quotient
(Setoid.mk (fun α β => diff (MonoidHom.id H) α β = 1)
⟨fun α => diff_self (MonoidHom.id H) α, fun h => by rw [← diff_inv, h, inv_one],
fun h h' => by rw [← diff_mul_diff, h, h', one_mul]⟩)
#align subgroup.quotient_diff Subgroup.QuotientDiff
instance : Inhabited H.QuotientDiff := by
dsimp [QuotientDiff] -- Porting note: Added `dsimp`
infer_instance
| Mathlib/GroupTheory/SchurZassenhaus.lean | 48 | 62 | theorem smul_diff_smul' [hH : Normal H] (g : Gᵐᵒᵖ) :
diff (MonoidHom.id H) (g • α) (g • β) =
⟨g.unop⁻¹ * (diff (MonoidHom.id H) α β : H) * g.unop,
hH.mem_comm ((congr_arg (· ∈ H) (mul_inv_cancel_left _ _)).mpr (SetLike.coe_mem _))⟩ := by |
letI := H.fintypeQuotientOfFiniteIndex
let ϕ : H →* H :=
{ toFun := fun h =>
⟨g.unop⁻¹ * h * g.unop,
hH.mem_comm ((congr_arg (· ∈ H) (mul_inv_cancel_left _ _)).mpr (SetLike.coe_mem _))⟩
map_one' := by rw [Subtype.ext_iff, coe_mk, coe_one, mul_one, inv_mul_self]
map_mul' := fun h₁ h₂ => by
simp only [Subtype.ext_iff, coe_mk, coe_mul, mul_assoc, mul_inv_cancel_left] }
refine (Fintype.prod_equiv (MulAction.toPerm g).symm _ _ fun x ↦ ?_).trans (map_prod ϕ _ _).symm
simp only [ϕ, smul_apply_eq_smul_apply_inv_smul, smul_eq_mul_unop, mul_inv_rev, mul_assoc,
MonoidHom.id_apply, toPerm_symm_apply, MonoidHom.coe_mk, OneHom.coe_mk]
| 0 |
import Mathlib.Data.Real.NNReal
import Mathlib.RingTheory.Valuation.Basic
noncomputable section
open Function Multiplicative
open scoped NNReal
variable {R : Type*} [Ring R] {Γ₀ : Type*} [LinearOrderedCommGroupWithZero Γ₀]
namespace Valuation
class RankOne (v : Valuation R Γ₀) where
hom : Γ₀ →*₀ ℝ≥0
strictMono' : StrictMono hom
nontrivial' : ∃ r : R, v r ≠ 0 ∧ v r ≠ 1
namespace RankOne
variable (v : Valuation R Γ₀) [RankOne v]
lemma strictMono : StrictMono (hom v) := strictMono'
lemma nontrivial : ∃ r : R, v r ≠ 0 ∧ v r ≠ 1 := nontrivial'
theorem zero_of_hom_zero {x : Γ₀} (hx : hom v x = 0) : x = 0 := by
refine (eq_of_le_of_not_lt (zero_le' (a := x)) fun h_lt ↦ ?_).symm
have hs := strictMono v h_lt
rw [_root_.map_zero, hx] at hs
exact hs.false
theorem hom_eq_zero_iff {x : Γ₀} : RankOne.hom v x = 0 ↔ x = 0 :=
⟨fun h ↦ zero_of_hom_zero v h, fun h ↦ by rw [h, _root_.map_zero]⟩
def unit : Γ₀ˣ :=
Units.mk0 (v (nontrivial v).choose) ((nontrivial v).choose_spec).1
| Mathlib/RingTheory/Valuation/RankOne.lean | 67 | 69 | theorem unit_ne_one : unit v ≠ 1 := by |
rw [Ne, ← Units.eq_iff, Units.val_one]
exact ((nontrivial v).choose_spec ).2
| 0 |
import Mathlib.Algebra.Associated
import Mathlib.Algebra.BigOperators.Finsupp
#align_import algebra.big_operators.associated from "leanprover-community/mathlib"@"f7fc89d5d5ff1db2d1242c7bb0e9062ce47ef47c"
variable {α β γ δ : Type*}
-- the same local notation used in `Algebra.Associated`
local infixl:50 " ~ᵤ " => Associated
theorem Prod.associated_iff {M N : Type*} [Monoid M] [Monoid N] {x z : M × N} :
x ~ᵤ z ↔ x.1 ~ᵤ z.1 ∧ x.2 ~ᵤ z.2 :=
⟨fun ⟨u, hu⟩ => ⟨⟨(MulEquiv.prodUnits.toFun u).1, (Prod.eq_iff_fst_eq_snd_eq.1 hu).1⟩,
⟨(MulEquiv.prodUnits.toFun u).2, (Prod.eq_iff_fst_eq_snd_eq.1 hu).2⟩⟩,
fun ⟨⟨u₁, h₁⟩, ⟨u₂, h₂⟩⟩ =>
⟨MulEquiv.prodUnits.invFun (u₁, u₂), Prod.eq_iff_fst_eq_snd_eq.2 ⟨h₁, h₂⟩⟩⟩
theorem Associated.prod {M : Type*} [CommMonoid M] {ι : Type*} (s : Finset ι) (f : ι → M)
(g : ι → M) (h : ∀ i, i ∈ s → (f i) ~ᵤ (g i)) : (∏ i ∈ s, f i) ~ᵤ (∏ i ∈ s, g i) := by
induction s using Finset.induction with
| empty =>
simp only [Finset.prod_empty]
rfl
| @insert j s hjs IH =>
classical
convert_to (∏ i ∈ insert j s, f i) ~ᵤ (∏ i ∈ insert j s, g i)
rw [Finset.prod_insert hjs, Finset.prod_insert hjs]
exact Associated.mul_mul (h j (Finset.mem_insert_self j s))
(IH (fun i hi ↦ h i (Finset.mem_insert_of_mem hi)))
theorem exists_associated_mem_of_dvd_prod [CancelCommMonoidWithZero α] {p : α} (hp : Prime p)
{s : Multiset α} : (∀ r ∈ s, Prime r) → p ∣ s.prod → ∃ q ∈ s, p ~ᵤ q :=
Multiset.induction_on s (by simp [mt isUnit_iff_dvd_one.2 hp.not_unit]) fun a s ih hs hps => by
rw [Multiset.prod_cons] at hps
cases' hp.dvd_or_dvd hps with h h
· have hap := hs a (Multiset.mem_cons.2 (Or.inl rfl))
exact ⟨a, Multiset.mem_cons_self a _, hp.associated_of_dvd hap h⟩
· rcases ih (fun r hr => hs _ (Multiset.mem_cons.2 (Or.inr hr))) h with ⟨q, hq₁, hq₂⟩
exact ⟨q, Multiset.mem_cons.2 (Or.inr hq₁), hq₂⟩
#align exists_associated_mem_of_dvd_prod exists_associated_mem_of_dvd_prod
theorem Multiset.prod_primes_dvd [CancelCommMonoidWithZero α]
[∀ a : α, DecidablePred (Associated a)] {s : Multiset α} (n : α) (h : ∀ a ∈ s, Prime a)
(div : ∀ a ∈ s, a ∣ n) (uniq : ∀ a, s.countP (Associated a) ≤ 1) : s.prod ∣ n := by
induction' s using Multiset.induction_on with a s induct n primes divs generalizing n
· simp only [Multiset.prod_zero, one_dvd]
· rw [Multiset.prod_cons]
obtain ⟨k, rfl⟩ : a ∣ n := div a (Multiset.mem_cons_self a s)
apply mul_dvd_mul_left a
refine induct _ (fun a ha => h a (Multiset.mem_cons_of_mem ha)) (fun b b_in_s => ?_)
fun a => (Multiset.countP_le_of_le _ (Multiset.le_cons_self _ _)).trans (uniq a)
have b_div_n := div b (Multiset.mem_cons_of_mem b_in_s)
have a_prime := h a (Multiset.mem_cons_self a s)
have b_prime := h b (Multiset.mem_cons_of_mem b_in_s)
refine (b_prime.dvd_or_dvd b_div_n).resolve_left fun b_div_a => ?_
have assoc := b_prime.associated_of_dvd a_prime b_div_a
have := uniq a
rw [Multiset.countP_cons_of_pos _ (Associated.refl _), Nat.succ_le_succ_iff, ← not_lt,
Multiset.countP_pos] at this
exact this ⟨b, b_in_s, assoc.symm⟩
#align multiset.prod_primes_dvd Multiset.prod_primes_dvd
| Mathlib/Algebra/BigOperators/Associated.lean | 103 | 111 | theorem Finset.prod_primes_dvd [CancelCommMonoidWithZero α] [Unique αˣ] {s : Finset α} (n : α)
(h : ∀ a ∈ s, Prime a) (div : ∀ a ∈ s, a ∣ n) : (∏ p ∈ s, p) ∣ n := by |
classical
exact
Multiset.prod_primes_dvd n (by simpa only [Multiset.map_id', Finset.mem_def] using h)
(by simpa only [Multiset.map_id', Finset.mem_def] using div)
(by
simp only [Multiset.map_id', associated_eq_eq, Multiset.countP_eq_card_filter,
← s.val.count_eq_card_filter_eq, ← Multiset.nodup_iff_count_le_one, s.nodup])
| 0 |
import Mathlib.Data.Fin.VecNotation
import Mathlib.SetTheory.Cardinal.Basic
#align_import model_theory.basic from "leanprover-community/mathlib"@"369525b73f229ccd76a6ec0e0e0bf2be57599768"
set_option autoImplicit true
universe u v u' v' w w'
open Cardinal
open Cardinal
namespace FirstOrder
-- intended to be used with explicit universe parameters
@[nolint checkUnivs]
structure Language where
Functions : ℕ → Type u
Relations : ℕ → Type v
#align first_order.language FirstOrder.Language
--@[simp]
def Sequence₂ (a₀ a₁ a₂ : Type u) : ℕ → Type u
| 0 => a₀
| 1 => a₁
| 2 => a₂
| _ => PEmpty
#align first_order.sequence₂ FirstOrder.Sequence₂
namespace Sequence₂
variable (a₀ a₁ a₂ : Type u)
instance inhabited₀ [h : Inhabited a₀] : Inhabited (Sequence₂ a₀ a₁ a₂ 0) :=
h
#align first_order.sequence₂.inhabited₀ FirstOrder.Sequence₂.inhabited₀
instance inhabited₁ [h : Inhabited a₁] : Inhabited (Sequence₂ a₀ a₁ a₂ 1) :=
h
#align first_order.sequence₂.inhabited₁ FirstOrder.Sequence₂.inhabited₁
instance inhabited₂ [h : Inhabited a₂] : Inhabited (Sequence₂ a₀ a₁ a₂ 2) :=
h
#align first_order.sequence₂.inhabited₂ FirstOrder.Sequence₂.inhabited₂
instance {n : ℕ} : IsEmpty (Sequence₂ a₀ a₁ a₂ (n + 3)) := inferInstanceAs (IsEmpty PEmpty)
@[simp]
theorem lift_mk {i : ℕ} :
Cardinal.lift.{v,u} #(Sequence₂ a₀ a₁ a₂ i)
= #(Sequence₂ (ULift.{v,u} a₀) (ULift.{v,u} a₁) (ULift.{v,u} a₂) i) := by
rcases i with (_ | _ | _ | i) <;>
simp only [Sequence₂, mk_uLift, Nat.succ_ne_zero, IsEmpty.forall_iff, Nat.succ.injEq,
add_eq_zero, OfNat.ofNat_ne_zero, and_false, one_ne_zero, mk_eq_zero, lift_zero]
#align first_order.sequence₂.lift_mk FirstOrder.Sequence₂.lift_mk
@[simp]
| Mathlib/ModelTheory/Basic.lean | 104 | 106 | theorem sum_card : Cardinal.sum (fun i => #(Sequence₂ a₀ a₁ a₂ i)) = #a₀ + #a₁ + #a₂ := by |
rw [sum_nat_eq_add_sum_succ, sum_nat_eq_add_sum_succ, sum_nat_eq_add_sum_succ]
simp [add_assoc, Sequence₂]
| 0 |
import Mathlib.Geometry.Manifold.MFDeriv.SpecificFunctions
noncomputable section
open scoped Manifold
open Bundle Set Topology
variable {𝕜 : Type*} [NontriviallyNormedField 𝕜]
{E : Type*} [NormedAddCommGroup E] [NormedSpace 𝕜 E] {H : Type*} [TopologicalSpace H]
(I : ModelWithCorners 𝕜 E H) {M : Type*} [TopologicalSpace M] [ChartedSpace H M]
{E' : Type*} [NormedAddCommGroup E'] [NormedSpace 𝕜 E'] {H' : Type*} [TopologicalSpace H']
(I' : ModelWithCorners 𝕜 E' H') {M' : Type*} [TopologicalSpace M'] [ChartedSpace H' M']
{E'' : Type*} [NormedAddCommGroup E''] [NormedSpace 𝕜 E''] {H'' : Type*} [TopologicalSpace H'']
(I'' : ModelWithCorners 𝕜 E'' H'') {M'' : Type*} [TopologicalSpace M''] [ChartedSpace H'' M'']
section Charts
variable [SmoothManifoldWithCorners I M] [SmoothManifoldWithCorners I' M']
[SmoothManifoldWithCorners I'' M''] {e : PartialHomeomorph M H}
theorem mdifferentiableAt_atlas (h : e ∈ atlas H M) {x : M} (hx : x ∈ e.source) :
MDifferentiableAt I I e x := by
rw [mdifferentiableAt_iff]
refine ⟨(e.continuousOn x hx).continuousAt (e.open_source.mem_nhds hx), ?_⟩
have mem :
I ((chartAt H x : M → H) x) ∈ I.symm ⁻¹' ((chartAt H x).symm ≫ₕ e).source ∩ range I := by
simp only [hx, mfld_simps]
have : (chartAt H x).symm.trans e ∈ contDiffGroupoid ∞ I :=
HasGroupoid.compatible (chart_mem_atlas H x) h
have A :
ContDiffOn 𝕜 ∞ (I ∘ (chartAt H x).symm.trans e ∘ I.symm)
(I.symm ⁻¹' ((chartAt H x).symm.trans e).source ∩ range I) :=
this.1
have B := A.differentiableOn le_top (I ((chartAt H x : M → H) x)) mem
simp only [mfld_simps] at B
rw [inter_comm, differentiableWithinAt_inter] at B
· simpa only [mfld_simps]
· apply IsOpen.mem_nhds ((PartialHomeomorph.open_source _).preimage I.continuous_symm) mem.1
#align mdifferentiable_at_atlas mdifferentiableAt_atlas
theorem mdifferentiableOn_atlas (h : e ∈ atlas H M) : MDifferentiableOn I I e e.source :=
fun _x hx => (mdifferentiableAt_atlas I h hx).mdifferentiableWithinAt
#align mdifferentiable_on_atlas mdifferentiableOn_atlas
theorem mdifferentiableAt_atlas_symm (h : e ∈ atlas H M) {x : H} (hx : x ∈ e.target) :
MDifferentiableAt I I e.symm x := by
rw [mdifferentiableAt_iff]
refine ⟨(e.continuousOn_symm x hx).continuousAt (e.open_target.mem_nhds hx), ?_⟩
have mem : I x ∈ I.symm ⁻¹' (e.symm ≫ₕ chartAt H (e.symm x)).source ∩ range I := by
simp only [hx, mfld_simps]
have : e.symm.trans (chartAt H (e.symm x)) ∈ contDiffGroupoid ∞ I :=
HasGroupoid.compatible h (chart_mem_atlas H _)
have A :
ContDiffOn 𝕜 ∞ (I ∘ e.symm.trans (chartAt H (e.symm x)) ∘ I.symm)
(I.symm ⁻¹' (e.symm.trans (chartAt H (e.symm x))).source ∩ range I) :=
this.1
have B := A.differentiableOn le_top (I x) mem
simp only [mfld_simps] at B
rw [inter_comm, differentiableWithinAt_inter] at B
· simpa only [mfld_simps]
· apply IsOpen.mem_nhds ((PartialHomeomorph.open_source _).preimage I.continuous_symm) mem.1
#align mdifferentiable_at_atlas_symm mdifferentiableAt_atlas_symm
theorem mdifferentiableOn_atlas_symm (h : e ∈ atlas H M) : MDifferentiableOn I I e.symm e.target :=
fun _x hx => (mdifferentiableAt_atlas_symm I h hx).mdifferentiableWithinAt
#align mdifferentiable_on_atlas_symm mdifferentiableOn_atlas_symm
theorem mdifferentiable_of_mem_atlas (h : e ∈ atlas H M) : e.MDifferentiable I I :=
⟨mdifferentiableOn_atlas I h, mdifferentiableOn_atlas_symm I h⟩
#align mdifferentiable_of_mem_atlas mdifferentiable_of_mem_atlas
theorem mdifferentiable_chart (x : M) : (chartAt H x).MDifferentiable I I :=
mdifferentiable_of_mem_atlas _ (chart_mem_atlas _ _)
#align mdifferentiable_chart mdifferentiable_chart
| Mathlib/Geometry/Manifold/MFDeriv/Atlas.lean | 146 | 153 | theorem tangentMap_chart {p q : TangentBundle I M} (h : q.1 ∈ (chartAt H p.1).source) :
tangentMap I I (chartAt H p.1) q =
(TotalSpace.toProd _ _).symm
((chartAt (ModelProd H E) p : TangentBundle I M → ModelProd H E) q) := by |
dsimp [tangentMap]
rw [MDifferentiableAt.mfderiv]
· rfl
· exact mdifferentiableAt_atlas _ (chart_mem_atlas _ _) h
| 0 |
import Mathlib.Order.Filter.Lift
import Mathlib.Topology.Separation
import Mathlib.Order.Interval.Set.Monotone
#align_import topology.filter from "leanprover-community/mathlib"@"4c19a16e4b705bf135cf9a80ac18fcc99c438514"
open Set Filter TopologicalSpace
open Filter Topology
variable {ι : Sort*} {α β X Y : Type*}
namespace Filter
instance : TopologicalSpace (Filter α) :=
generateFrom <| range <| Iic ∘ 𝓟
theorem isOpen_Iic_principal {s : Set α} : IsOpen (Iic (𝓟 s)) :=
GenerateOpen.basic _ (mem_range_self _)
#align filter.is_open_Iic_principal Filter.isOpen_Iic_principal
theorem isOpen_setOf_mem {s : Set α} : IsOpen { l : Filter α | s ∈ l } := by
simpa only [Iic_principal] using isOpen_Iic_principal
#align filter.is_open_set_of_mem Filter.isOpen_setOf_mem
| Mathlib/Topology/Filter.lean | 59 | 66 | theorem isTopologicalBasis_Iic_principal :
IsTopologicalBasis (range (Iic ∘ 𝓟 : Set α → Set (Filter α))) :=
{ exists_subset_inter := by |
rintro _ ⟨s, rfl⟩ _ ⟨t, rfl⟩ l hl
exact ⟨Iic (𝓟 s) ∩ Iic (𝓟 t), ⟨s ∩ t, by simp⟩, hl, Subset.rfl⟩
sUnion_eq := sUnion_eq_univ_iff.2 fun l => ⟨Iic ⊤, ⟨univ, congr_arg Iic principal_univ⟩,
mem_Iic.2 le_top⟩
eq_generateFrom := rfl }
| 0 |
import Mathlib.GroupTheory.Perm.Cycle.Basic
#align_import group_theory.perm.cycle.basic from "leanprover-community/mathlib"@"e8638a0fcaf73e4500469f368ef9494e495099b3"
open Equiv Function Finset
variable {ι α β : Type*}
namespace Equiv.Perm
section Generation
variable [Finite β]
open Subgroup
theorem closure_isCycle : closure { σ : Perm β | IsCycle σ } = ⊤ := by
classical
cases nonempty_fintype β
exact
top_le_iff.mp (le_trans (ge_of_eq closure_isSwap) (closure_mono fun _ => IsSwap.isCycle))
#align equiv.perm.closure_is_cycle Equiv.Perm.closure_isCycle
variable [DecidableEq α] [Fintype α]
| Mathlib/GroupTheory/Perm/Closure.lean | 46 | 93 | theorem closure_cycle_adjacent_swap {σ : Perm α} (h1 : IsCycle σ) (h2 : σ.support = ⊤) (x : α) :
closure ({σ, swap x (σ x)} : Set (Perm α)) = ⊤ := by |
let H := closure ({σ, swap x (σ x)} : Set (Perm α))
have h3 : σ ∈ H := subset_closure (Set.mem_insert σ _)
have h4 : swap x (σ x) ∈ H := subset_closure (Set.mem_insert_of_mem _ (Set.mem_singleton _))
have step1 : ∀ n : ℕ, swap ((σ ^ n) x) ((σ ^ (n + 1) : Perm α) x) ∈ H := by
intro n
induction' n with n ih
· exact subset_closure (Set.mem_insert_of_mem _ (Set.mem_singleton _))
· convert H.mul_mem (H.mul_mem h3 ih) (H.inv_mem h3)
simp_rw [mul_swap_eq_swap_mul, mul_inv_cancel_right, pow_succ']
rfl
have step2 : ∀ n : ℕ, swap x ((σ ^ n) x) ∈ H := by
intro n
induction' n with n ih
· simp only [Nat.zero_eq, pow_zero, coe_one, id_eq, swap_self, Set.mem_singleton_iff]
convert H.one_mem
· by_cases h5 : x = (σ ^ n) x
· rw [pow_succ', mul_apply, ← h5]
exact h4
by_cases h6 : x = (σ ^ (n + 1) : Perm α) x
· rw [← h6, swap_self]
exact H.one_mem
rw [swap_comm, ← swap_mul_swap_mul_swap h5 h6]
exact H.mul_mem (H.mul_mem (step1 n) ih) (step1 n)
have step3 : ∀ y : α, swap x y ∈ H := by
intro y
have hx : x ∈ (⊤ : Finset α) := Finset.mem_univ x
rw [← h2, mem_support] at hx
have hy : y ∈ (⊤ : Finset α) := Finset.mem_univ y
rw [← h2, mem_support] at hy
cases' IsCycle.exists_pow_eq h1 hx hy with n hn
rw [← hn]
exact step2 n
have step4 : ∀ y z : α, swap y z ∈ H := by
intro y z
by_cases h5 : z = x
· rw [h5, swap_comm]
exact step3 y
by_cases h6 : z = y
· rw [h6, swap_self]
exact H.one_mem
rw [← swap_mul_swap_mul_swap h5 h6, swap_comm z x]
exact H.mul_mem (H.mul_mem (step3 y) (step3 z)) (step3 y)
rw [eq_top_iff, ← closure_isSwap, closure_le]
rintro τ ⟨y, z, _, h6⟩
rw [h6]
exact step4 y z
| 0 |
import Mathlib.Algebra.Ring.Prod
import Mathlib.GroupTheory.OrderOfElement
import Mathlib.Tactic.FinCases
#align_import data.zmod.basic from "leanprover-community/mathlib"@"74ad1c88c77e799d2fea62801d1dbbd698cff1b7"
assert_not_exists Submodule
open Function
namespace ZMod
instance charZero : CharZero (ZMod 0) := inferInstanceAs (CharZero ℤ)
def val : ∀ {n : ℕ}, ZMod n → ℕ
| 0 => Int.natAbs
| n + 1 => ((↑) : Fin (n + 1) → ℕ)
#align zmod.val ZMod.val
theorem val_lt {n : ℕ} [NeZero n] (a : ZMod n) : a.val < n := by
cases n
· cases NeZero.ne 0 rfl
exact Fin.is_lt a
#align zmod.val_lt ZMod.val_lt
theorem val_le {n : ℕ} [NeZero n] (a : ZMod n) : a.val ≤ n :=
a.val_lt.le
#align zmod.val_le ZMod.val_le
@[simp]
theorem val_zero : ∀ {n}, (0 : ZMod n).val = 0
| 0 => rfl
| _ + 1 => rfl
#align zmod.val_zero ZMod.val_zero
@[simp]
theorem val_one' : (1 : ZMod 0).val = 1 :=
rfl
#align zmod.val_one' ZMod.val_one'
@[simp]
theorem val_neg' {n : ZMod 0} : (-n).val = n.val :=
Int.natAbs_neg n
#align zmod.val_neg' ZMod.val_neg'
@[simp]
theorem val_mul' {m n : ZMod 0} : (m * n).val = m.val * n.val :=
Int.natAbs_mul m n
#align zmod.val_mul' ZMod.val_mul'
@[simp]
theorem val_natCast {n : ℕ} (a : ℕ) : (a : ZMod n).val = a % n := by
cases n
· rw [Nat.mod_zero]
exact Int.natAbs_ofNat a
· apply Fin.val_natCast
#align zmod.val_nat_cast ZMod.val_natCast
@[deprecated (since := "2024-04-17")]
alias val_nat_cast := val_natCast
theorem val_unit' {n : ZMod 0} : IsUnit n ↔ n.val = 1 := by
simp only [val]
rw [Int.isUnit_iff, Int.natAbs_eq_iff, Nat.cast_one]
lemma eq_one_of_isUnit_natCast {n : ℕ} (h : IsUnit (n : ZMod 0)) : n = 1 := by
rw [← Nat.mod_zero n, ← val_natCast, val_unit'.mp h]
theorem val_natCast_of_lt {n a : ℕ} (h : a < n) : (a : ZMod n).val = a := by
rwa [val_natCast, Nat.mod_eq_of_lt]
@[deprecated (since := "2024-04-17")]
alias val_nat_cast_of_lt := val_natCast_of_lt
instance charP (n : ℕ) : CharP (ZMod n) n where
cast_eq_zero_iff' := by
intro k
cases' n with n
· simp [zero_dvd_iff, Int.natCast_eq_zero, Nat.zero_eq]
· exact Fin.natCast_eq_zero
@[simp]
theorem addOrderOf_one (n : ℕ) : addOrderOf (1 : ZMod n) = n :=
CharP.eq _ (CharP.addOrderOf_one _) (ZMod.charP n)
#align zmod.add_order_of_one ZMod.addOrderOf_one
@[simp]
| Mathlib/Data/ZMod/Basic.lean | 122 | 126 | theorem addOrderOf_coe (a : ℕ) {n : ℕ} (n0 : n ≠ 0) : addOrderOf (a : ZMod n) = n / n.gcd a := by |
cases' a with a
· simp only [Nat.zero_eq, Nat.cast_zero, addOrderOf_zero, Nat.gcd_zero_right,
Nat.pos_of_ne_zero n0, Nat.div_self]
rw [← Nat.smul_one_eq_cast, addOrderOf_nsmul' _ a.succ_ne_zero, ZMod.addOrderOf_one]
| 0 |
import Mathlib.CategoryTheory.Abelian.Opposite
import Mathlib.CategoryTheory.Abelian.Homology
import Mathlib.Algebra.Homology.Additive
import Mathlib.Algebra.Homology.ShortComplex.HomologicalComplex
#align_import algebra.homology.opposite from "leanprover-community/mathlib"@"8c75ef3517d4106e89fe524e6281d0b0545f47fc"
noncomputable section
open Opposite CategoryTheory CategoryTheory.Limits
section
variable {V : Type*} [Category V] [Abelian V]
theorem imageToKernel_op {X Y Z : V} (f : X ⟶ Y) (g : Y ⟶ Z) (w : f ≫ g = 0) :
imageToKernel g.op f.op (by rw [← op_comp, w, op_zero]) =
(imageSubobjectIso _ ≪≫ (imageOpOp _).symm).hom ≫
(cokernel.desc f (factorThruImage g)
(by rw [← cancel_mono (image.ι g), Category.assoc, image.fac, w, zero_comp])).op ≫
(kernelSubobjectIso _ ≪≫ kernelOpOp _).inv := by
ext
simp only [Iso.trans_hom, Iso.symm_hom, Iso.trans_inv, kernelOpOp_inv, Category.assoc,
imageToKernel_arrow, kernelSubobject_arrow', kernel.lift_ι, ← op_comp, cokernel.π_desc,
← imageSubobject_arrow, ← imageUnopOp_inv_comp_op_factorThruImage g.op]
rfl
#align image_to_kernel_op imageToKernel_op
| Mathlib/Algebra/Homology/Opposite.lean | 53 | 63 | theorem imageToKernel_unop {X Y Z : Vᵒᵖ} (f : X ⟶ Y) (g : Y ⟶ Z) (w : f ≫ g = 0) :
imageToKernel g.unop f.unop (by rw [← unop_comp, w, unop_zero]) =
(imageSubobjectIso _ ≪≫ (imageUnopUnop _).symm).hom ≫
(cokernel.desc f (factorThruImage g)
(by rw [← cancel_mono (image.ι g), Category.assoc, image.fac, w, zero_comp])).unop ≫
(kernelSubobjectIso _ ≪≫ kernelUnopUnop _).inv := by |
ext
dsimp only [imageUnopUnop]
simp only [Iso.trans_hom, Iso.symm_hom, Iso.trans_inv, kernelUnopUnop_inv, Category.assoc,
imageToKernel_arrow, kernelSubobject_arrow', kernel.lift_ι, cokernel.π_desc, Iso.unop_inv,
← unop_comp, factorThruImage_comp_imageUnopOp_inv, Quiver.Hom.unop_op, imageSubobject_arrow]
| 0 |
import Mathlib.Algebra.BigOperators.Group.List
import Mathlib.Data.List.OfFn
import Mathlib.Data.Set.Pointwise.Basic
#align_import data.set.pointwise.list_of_fn from "leanprover-community/mathlib"@"f694c7dead66f5d4c80f446c796a5aad14707f0e"
namespace Set
variable {F α β γ : Type*}
variable [Monoid α] {s t : Set α} {a : α} {m n : ℕ}
open Pointwise
@[to_additive]
theorem mem_prod_list_ofFn {a : α} {s : Fin n → Set α} :
a ∈ (List.ofFn s).prod ↔ ∃ f : ∀ i : Fin n, s i, (List.ofFn fun i ↦ (f i : α)).prod = a := by
induction' n with n ih generalizing a
· simp_rw [List.ofFn_zero, List.prod_nil, Fin.exists_fin_zero_pi, eq_comm, Set.mem_one]
· simp_rw [List.ofFn_succ, List.prod_cons, Fin.exists_fin_succ_pi, Fin.cons_zero, Fin.cons_succ,
mem_mul, @ih, exists_exists_eq_and, SetCoe.exists, exists_prop]
#align set.mem_prod_list_of_fn Set.mem_prod_list_ofFn
#align set.mem_sum_list_of_fn Set.mem_sum_list_ofFn
@[to_additive]
| Mathlib/Data/Set/Pointwise/ListOfFn.lean | 36 | 47 | theorem mem_list_prod {l : List (Set α)} {a : α} :
a ∈ l.prod ↔
∃ l' : List (Σs : Set α, ↥s),
List.prod (l'.map fun x ↦ (Sigma.snd x : α)) = a ∧ l'.map Sigma.fst = l := by |
induction' l using List.ofFnRec with n f
simp only [mem_prod_list_ofFn, List.exists_iff_exists_tuple, List.map_ofFn, Function.comp,
List.ofFn_inj', Sigma.mk.inj_iff, and_left_comm, exists_and_left, exists_eq_left, heq_eq_eq]
constructor
· rintro ⟨fi, rfl⟩
exact ⟨fun i ↦ ⟨_, fi i⟩, rfl, rfl⟩
· rintro ⟨fi, rfl, rfl⟩
exact ⟨fun i ↦ _, rfl⟩
| 0 |
import Mathlib.Algebra.Polynomial.Monic
#align_import algebra.polynomial.big_operators from "leanprover-community/mathlib"@"47adfab39a11a072db552f47594bf8ed2cf8a722"
open Finset
open Multiset
open Polynomial
universe u w
variable {R : Type u} {ι : Type w}
namespace Polynomial
variable (s : Finset ι)
section CommRing
variable [CommRing R]
open Monic
-- Eventually this can be generalized with Vieta's formulas
-- plus the connection between roots and factorization.
| Mathlib/Algebra/Polynomial/BigOperators.lean | 253 | 259 | theorem multiset_prod_X_sub_C_nextCoeff (t : Multiset R) :
nextCoeff (t.map fun x => X - C x).prod = -t.sum := by |
rw [nextCoeff_multiset_prod]
· simp only [nextCoeff_X_sub_C]
exact t.sum_hom (-AddMonoidHom.id R)
· intros
apply monic_X_sub_C
| 0 |
import Mathlib.MeasureTheory.Constructions.Prod.Basic
import Mathlib.MeasureTheory.Group.Measure
#align_import measure_theory.group.prod from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844"
noncomputable section
open Set hiding prod_eq
open Function MeasureTheory
open Filter hiding map
open scoped Classical ENNReal Pointwise MeasureTheory
variable (G : Type*) [MeasurableSpace G]
variable [Group G] [MeasurableMul₂ G]
variable (μ ν : Measure G) [SigmaFinite ν] [SigmaFinite μ] {s : Set G}
@[to_additive "The map `(x, y) ↦ (x, x + y)` as a `MeasurableEquiv`."]
protected def MeasurableEquiv.shearMulRight [MeasurableInv G] : G × G ≃ᵐ G × G :=
{ Equiv.prodShear (Equiv.refl _) Equiv.mulLeft with
measurable_toFun := measurable_fst.prod_mk measurable_mul
measurable_invFun := measurable_fst.prod_mk <| measurable_fst.inv.mul measurable_snd }
#align measurable_equiv.shear_mul_right MeasurableEquiv.shearMulRight
#align measurable_equiv.shear_add_right MeasurableEquiv.shearAddRight
@[to_additive
"The map `(x, y) ↦ (x, y - x)` as a `MeasurableEquiv` with as inverse `(x, y) ↦ (x, y + x)`."]
protected def MeasurableEquiv.shearDivRight [MeasurableInv G] : G × G ≃ᵐ G × G :=
{ Equiv.prodShear (Equiv.refl _) Equiv.divRight with
measurable_toFun := measurable_fst.prod_mk <| measurable_snd.div measurable_fst
measurable_invFun := measurable_fst.prod_mk <| measurable_snd.mul measurable_fst }
#align measurable_equiv.shear_div_right MeasurableEquiv.shearDivRight
#align measurable_equiv.shear_sub_right MeasurableEquiv.shearSubRight
variable {G}
namespace MeasureTheory
open Measure
section LeftInvariant
@[to_additive measurePreserving_prod_add
" The shear mapping `(x, y) ↦ (x, x + y)` preserves the measure `μ × ν`. "]
theorem measurePreserving_prod_mul [IsMulLeftInvariant ν] :
MeasurePreserving (fun z : G × G => (z.1, z.1 * z.2)) (μ.prod ν) (μ.prod ν) :=
(MeasurePreserving.id μ).skew_product measurable_mul <|
Filter.eventually_of_forall <| map_mul_left_eq_self ν
#align measure_theory.measure_preserving_prod_mul MeasureTheory.measurePreserving_prod_mul
#align measure_theory.measure_preserving_prod_add MeasureTheory.measurePreserving_prod_add
@[to_additive measurePreserving_prod_add_swap
" The map `(x, y) ↦ (y, y + x)` sends the measure `μ × ν` to `ν × μ`. "]
theorem measurePreserving_prod_mul_swap [IsMulLeftInvariant μ] :
MeasurePreserving (fun z : G × G => (z.2, z.2 * z.1)) (μ.prod ν) (ν.prod μ) :=
(measurePreserving_prod_mul ν μ).comp measurePreserving_swap
#align measure_theory.measure_preserving_prod_mul_swap MeasureTheory.measurePreserving_prod_mul_swap
#align measure_theory.measure_preserving_prod_add_swap MeasureTheory.measurePreserving_prod_add_swap
@[to_additive]
theorem measurable_measure_mul_right (hs : MeasurableSet s) :
Measurable fun x => μ ((fun y => y * x) ⁻¹' s) := by
suffices
Measurable fun y =>
μ ((fun x => (x, y)) ⁻¹' ((fun z : G × G => ((1 : G), z.1 * z.2)) ⁻¹' univ ×ˢ s))
by convert this using 1; ext1 x; congr 1 with y : 1; simp
apply measurable_measure_prod_mk_right
apply measurable_const.prod_mk measurable_mul (MeasurableSet.univ.prod hs)
infer_instance
#align measure_theory.measurable_measure_mul_right MeasureTheory.measurable_measure_mul_right
#align measure_theory.measurable_measure_add_right MeasureTheory.measurable_measure_add_right
variable [MeasurableInv G]
@[to_additive measurePreserving_prod_neg_add
"The map `(x, y) ↦ (x, - x + y)` is measure-preserving."]
theorem measurePreserving_prod_inv_mul [IsMulLeftInvariant ν] :
MeasurePreserving (fun z : G × G => (z.1, z.1⁻¹ * z.2)) (μ.prod ν) (μ.prod ν) :=
(measurePreserving_prod_mul μ ν).symm <| MeasurableEquiv.shearMulRight G
#align measure_theory.measure_preserving_prod_inv_mul MeasureTheory.measurePreserving_prod_inv_mul
#align measure_theory.measure_preserving_prod_neg_add MeasureTheory.measurePreserving_prod_neg_add
variable [IsMulLeftInvariant μ]
@[to_additive measurePreserving_prod_neg_add_swap
"The map `(x, y) ↦ (y, - y + x)` sends `μ × ν` to `ν × μ`."]
theorem measurePreserving_prod_inv_mul_swap :
MeasurePreserving (fun z : G × G => (z.2, z.2⁻¹ * z.1)) (μ.prod ν) (ν.prod μ) :=
(measurePreserving_prod_inv_mul ν μ).comp measurePreserving_swap
#align measure_theory.measure_preserving_prod_inv_mul_swap MeasureTheory.measurePreserving_prod_inv_mul_swap
#align measure_theory.measure_preserving_prod_neg_add_swap MeasureTheory.measurePreserving_prod_neg_add_swap
@[to_additive measurePreserving_add_prod_neg
"The map `(x, y) ↦ (y + x, - x)` is measure-preserving."]
| Mathlib/MeasureTheory/Group/Prod.lean | 151 | 156 | theorem measurePreserving_mul_prod_inv [IsMulLeftInvariant ν] :
MeasurePreserving (fun z : G × G => (z.2 * z.1, z.1⁻¹)) (μ.prod ν) (μ.prod ν) := by |
convert (measurePreserving_prod_inv_mul_swap ν μ).comp (measurePreserving_prod_mul_swap μ ν)
using 1
ext1 ⟨x, y⟩
simp_rw [Function.comp_apply, mul_inv_rev, inv_mul_cancel_right]
| 0 |
import Mathlib.Order.Filter.Basic
import Mathlib.Topology.Bases
import Mathlib.Data.Set.Accumulate
import Mathlib.Topology.Bornology.Basic
import Mathlib.Topology.LocallyFinite
open Set Filter Topology TopologicalSpace Classical Function
universe u v
variable {X : Type u} {Y : Type v} {ι : Type*}
variable [TopologicalSpace X] [TopologicalSpace Y] {s t : Set X}
-- compact sets
section Compact
lemma IsCompact.exists_clusterPt (hs : IsCompact s) {f : Filter X} [NeBot f] (hf : f ≤ 𝓟 s) :
∃ x ∈ s, ClusterPt x f := hs hf
lemma IsCompact.exists_mapClusterPt {ι : Type*} (hs : IsCompact s) {f : Filter ι} [NeBot f]
{u : ι → X} (hf : Filter.map u f ≤ 𝓟 s) :
∃ x ∈ s, MapClusterPt x f u := hs hf
theorem IsCompact.compl_mem_sets (hs : IsCompact s) {f : Filter X} (hf : ∀ x ∈ s, sᶜ ∈ 𝓝 x ⊓ f) :
sᶜ ∈ f := by
contrapose! hf
simp only [not_mem_iff_inf_principal_compl, compl_compl, inf_assoc] at hf ⊢
exact @hs _ hf inf_le_right
#align is_compact.compl_mem_sets IsCompact.compl_mem_sets
theorem IsCompact.compl_mem_sets_of_nhdsWithin (hs : IsCompact s) {f : Filter X}
(hf : ∀ x ∈ s, ∃ t ∈ 𝓝[s] x, tᶜ ∈ f) : sᶜ ∈ f := by
refine hs.compl_mem_sets fun x hx => ?_
rcases hf x hx with ⟨t, ht, hst⟩
replace ht := mem_inf_principal.1 ht
apply mem_inf_of_inter ht hst
rintro x ⟨h₁, h₂⟩ hs
exact h₂ (h₁ hs)
#align is_compact.compl_mem_sets_of_nhds_within IsCompact.compl_mem_sets_of_nhdsWithin
@[elab_as_elim]
| Mathlib/Topology/Compactness/Compact.lean | 70 | 75 | theorem IsCompact.induction_on (hs : IsCompact s) {p : Set X → Prop} (he : p ∅)
(hmono : ∀ ⦃s t⦄, s ⊆ t → p t → p s) (hunion : ∀ ⦃s t⦄, p s → p t → p (s ∪ t))
(hnhds : ∀ x ∈ s, ∃ t ∈ 𝓝[s] x, p t) : p s := by |
let f : Filter X := comk p he (fun _t ht _s hsub ↦ hmono hsub ht) (fun _s hs _t ht ↦ hunion hs ht)
have : sᶜ ∈ f := hs.compl_mem_sets_of_nhdsWithin (by simpa [f] using hnhds)
rwa [← compl_compl s]
| 0 |
import Mathlib.Analysis.NormedSpace.Exponential
import Mathlib.Analysis.NormedSpace.ProdLp
import Mathlib.Topology.Instances.TrivSqZeroExt
#align_import analysis.normed_space.triv_sq_zero_ext from "leanprover-community/mathlib"@"88a563b158f59f2983cfad685664da95502e8cdd"
variable (𝕜 : Type*) {S R M : Type*}
local notation "tsze" => TrivSqZeroExt
open NormedSpace -- For `exp`.
namespace TrivSqZeroExt
section Topology
section Ring
variable [Field 𝕜] [CharZero 𝕜] [Ring R] [AddCommGroup M]
[Algebra 𝕜 R] [Module 𝕜 M] [Module R M] [Module Rᵐᵒᵖ M]
[SMulCommClass R Rᵐᵒᵖ M] [IsScalarTower 𝕜 R M] [IsScalarTower 𝕜 Rᵐᵒᵖ M]
[TopologicalSpace R] [TopologicalSpace M]
[TopologicalRing R] [TopologicalAddGroup M] [ContinuousSMul R M] [ContinuousSMul Rᵐᵒᵖ M]
theorem snd_expSeries_of_smul_comm
(x : tsze R M) (hx : MulOpposite.op x.fst • x.snd = x.fst • x.snd) (n : ℕ) :
snd (expSeries 𝕜 (tsze R M) (n + 1) fun _ => x) = (expSeries 𝕜 R n fun _ => x.fst) • x.snd := by
simp_rw [expSeries_apply_eq, snd_smul, snd_pow_of_smul_comm _ _ hx, nsmul_eq_smul_cast 𝕜 (n + 1),
smul_smul, smul_assoc, Nat.factorial_succ, Nat.pred_succ, Nat.cast_mul, mul_inv_rev,
inv_mul_cancel_right₀ ((Nat.cast_ne_zero (R := 𝕜)).mpr <| Nat.succ_ne_zero n)]
| Mathlib/Analysis/NormedSpace/TrivSqZeroExt.lean | 91 | 100 | theorem hasSum_snd_expSeries_of_smul_comm (x : tsze R M)
(hx : MulOpposite.op x.fst • x.snd = x.fst • x.snd) {e : R}
(h : HasSum (fun n => expSeries 𝕜 R n fun _ => x.fst) e) :
HasSum (fun n => snd (expSeries 𝕜 (tsze R M) n fun _ => x)) (e • x.snd) := by |
rw [← hasSum_nat_add_iff' 1]
simp_rw [snd_expSeries_of_smul_comm _ _ hx]
simp_rw [expSeries_apply_eq] at *
rw [Finset.range_one, Finset.sum_singleton, Nat.factorial_zero, Nat.cast_one, pow_zero,
inv_one, one_smul, snd_one, sub_zero]
exact h.smul_const _
| 0 |
import Mathlib.RingTheory.RootsOfUnity.Basic
universe u
variable {L : Type u} [CommRing L] [IsDomain L]
variable (n : ℕ+)
theorem rootsOfUnity.integer_power_of_ringEquiv (g : L ≃+* L) :
∃ m : ℤ, ∀ t : rootsOfUnity n L, g (t : Lˣ) = (t ^ m : Lˣ) := by
obtain ⟨m, hm⟩ := MonoidHom.map_cyclic ((g : L ≃* L).restrictRootsOfUnity n).toMonoidHom
exact ⟨m, fun t ↦ Units.ext_iff.1 <| SetCoe.ext_iff.2 <| hm t⟩
theorem rootsOfUnity.integer_power_of_ringEquiv' (g : L ≃+* L) :
∃ m : ℤ, ∀ t ∈ rootsOfUnity n L, g (t : Lˣ) = (t ^ m : Lˣ) := by
simpa using rootsOfUnity.integer_power_of_ringEquiv n g
noncomputable def ModularCyclotomicCharacter_aux (g : L ≃+* L) (n : ℕ+) : ℤ :=
(rootsOfUnity.integer_power_of_ringEquiv n g).choose
-- the only thing we know about `ModularCyclotomicCharacter_aux g n`
theorem ModularCyclotomicCharacter_aux_spec (g : L ≃+* L) (n : ℕ+) :
∀ t : rootsOfUnity n L, g (t : Lˣ) = (t ^ (ModularCyclotomicCharacter_aux g n) : Lˣ) :=
(rootsOfUnity.integer_power_of_ringEquiv n g).choose_spec
noncomputable def ModularCyclotomicCharacter.toFun (n : ℕ+) (g : L ≃+* L) :
ZMod (Fintype.card (rootsOfUnity n L)) :=
ModularCyclotomicCharacter_aux g n
namespace ModularCyclotomicCharacter
local notation "χ₀" => ModularCyclotomicCharacter.toFun
set_option backward.synthInstance.canonInstances false in -- See https://github.com/leanprover-community/mathlib4/issues/12532
| Mathlib/NumberTheory/Cyclotomic/CyclotomicCharacter.lean | 105 | 109 | theorem toFun_spec (g : L ≃+* L) {n : ℕ+} (t : rootsOfUnity n L) :
g (t : Lˣ) = (t ^ (χ₀ n g).val : Lˣ) := by |
rw [ModularCyclotomicCharacter_aux_spec g n t, ← zpow_natCast, ModularCyclotomicCharacter.toFun,
ZMod.val_intCast, ← Subgroup.coe_zpow]
exact Units.ext_iff.1 <| SetCoe.ext_iff.2 <| zpow_eq_zpow_emod _ pow_card_eq_one
| 0 |
import Mathlib.MeasureTheory.OuterMeasure.OfFunction
import Mathlib.MeasureTheory.PiSystem
#align_import measure_theory.measure.outer_measure from "leanprover-community/mathlib"@"343e80208d29d2d15f8050b929aa50fe4ce71b55"
noncomputable section
open Set Function Filter
open scoped Classical NNReal Topology ENNReal
namespace MeasureTheory
namespace OuterMeasure
section CaratheodoryMeasurable
universe u
variable {α : Type u} (m : OuterMeasure α)
attribute [local simp] Set.inter_comm Set.inter_left_comm Set.inter_assoc
variable {s s₁ s₂ : Set α}
def IsCaratheodory (s : Set α) : Prop :=
∀ t, m t = m (t ∩ s) + m (t \ s)
#align measure_theory.outer_measure.is_caratheodory MeasureTheory.OuterMeasure.IsCaratheodory
theorem isCaratheodory_iff_le' {s : Set α} :
IsCaratheodory m s ↔ ∀ t, m (t ∩ s) + m (t \ s) ≤ m t :=
forall_congr' fun _ => le_antisymm_iff.trans <| and_iff_right <| measure_le_inter_add_diff _ _ _
#align measure_theory.outer_measure.is_caratheodory_iff_le' MeasureTheory.OuterMeasure.isCaratheodory_iff_le'
@[simp]
theorem isCaratheodory_empty : IsCaratheodory m ∅ := by simp [IsCaratheodory, m.empty, diff_empty]
#align measure_theory.outer_measure.is_caratheodory_empty MeasureTheory.OuterMeasure.isCaratheodory_empty
theorem isCaratheodory_compl : IsCaratheodory m s₁ → IsCaratheodory m s₁ᶜ := by
simp [IsCaratheodory, diff_eq, add_comm]
#align measure_theory.outer_measure.is_caratheodory_compl MeasureTheory.OuterMeasure.isCaratheodory_compl
@[simp]
theorem isCaratheodory_compl_iff : IsCaratheodory m sᶜ ↔ IsCaratheodory m s :=
⟨fun h => by simpa using isCaratheodory_compl m h, isCaratheodory_compl m⟩
#align measure_theory.outer_measure.is_caratheodory_compl_iff MeasureTheory.OuterMeasure.isCaratheodory_compl_iff
theorem isCaratheodory_union (h₁ : IsCaratheodory m s₁) (h₂ : IsCaratheodory m s₂) :
IsCaratheodory m (s₁ ∪ s₂) := fun t => by
rw [h₁ t, h₂ (t ∩ s₁), h₂ (t \ s₁), h₁ (t ∩ (s₁ ∪ s₂)), inter_diff_assoc _ _ s₁,
Set.inter_assoc _ _ s₁, inter_eq_self_of_subset_right Set.subset_union_left,
union_diff_left, h₂ (t ∩ s₁)]
simp [diff_eq, add_assoc]
#align measure_theory.outer_measure.is_caratheodory_union MeasureTheory.OuterMeasure.isCaratheodory_union
| Mathlib/MeasureTheory/OuterMeasure/Caratheodory.lean | 82 | 84 | theorem measure_inter_union (h : s₁ ∩ s₂ ⊆ ∅) (h₁ : IsCaratheodory m s₁) {t : Set α} :
m (t ∩ (s₁ ∪ s₂)) = m (t ∩ s₁) + m (t ∩ s₂) := by |
rw [h₁, Set.inter_assoc, Set.union_inter_cancel_left, inter_diff_assoc, union_diff_cancel_left h]
| 0 |
import Mathlib.Algebra.Order.Ring.Basic
import Mathlib.Computability.Primrec
import Mathlib.Tactic.Ring
import Mathlib.Tactic.Linarith
#align_import computability.ackermann from "leanprover-community/mathlib"@"9b2660e1b25419042c8da10bf411aa3c67f14383"
open Nat
def ack : ℕ → ℕ → ℕ
| 0, n => n + 1
| m + 1, 0 => ack m 1
| m + 1, n + 1 => ack m (ack (m + 1) n)
#align ack ack
@[simp]
theorem ack_zero (n : ℕ) : ack 0 n = n + 1 := by rw [ack]
#align ack_zero ack_zero
@[simp]
theorem ack_succ_zero (m : ℕ) : ack (m + 1) 0 = ack m 1 := by rw [ack]
#align ack_succ_zero ack_succ_zero
@[simp]
theorem ack_succ_succ (m n : ℕ) : ack (m + 1) (n + 1) = ack m (ack (m + 1) n) := by rw [ack]
#align ack_succ_succ ack_succ_succ
@[simp]
theorem ack_one (n : ℕ) : ack 1 n = n + 2 := by
induction' n with n IH
· rfl
· simp [IH]
#align ack_one ack_one
@[simp]
theorem ack_two (n : ℕ) : ack 2 n = 2 * n + 3 := by
induction' n with n IH
· rfl
· simpa [mul_succ]
#align ack_two ack_two
-- Porting note: re-written to get rid of ack_three_aux
@[simp]
theorem ack_three (n : ℕ) : ack 3 n = 2 ^ (n + 3) - 3 := by
induction' n with n IH
· rfl
· rw [ack_succ_succ, IH, ack_two, Nat.succ_add, Nat.pow_succ 2 (n + 3), mul_comm _ 2,
Nat.mul_sub_left_distrib, ← Nat.sub_add_comm, two_mul 3, Nat.add_sub_add_right]
have H : 2 * 3 ≤ 2 * 2 ^ 3 := by norm_num
apply H.trans
rw [_root_.mul_le_mul_left two_pos]
exact pow_le_pow_right one_le_two (Nat.le_add_left 3 n)
#align ack_three ack_three
theorem ack_pos : ∀ m n, 0 < ack m n
| 0, n => by simp
| m + 1, 0 => by
rw [ack_succ_zero]
apply ack_pos
| m + 1, n + 1 => by
rw [ack_succ_succ]
apply ack_pos
#align ack_pos ack_pos
theorem one_lt_ack_succ_left : ∀ m n, 1 < ack (m + 1) n
| 0, n => by simp
| m + 1, 0 => by
rw [ack_succ_zero]
apply one_lt_ack_succ_left
| m + 1, n + 1 => by
rw [ack_succ_succ]
apply one_lt_ack_succ_left
#align one_lt_ack_succ_left one_lt_ack_succ_left
theorem one_lt_ack_succ_right : ∀ m n, 1 < ack m (n + 1)
| 0, n => by simp
| m + 1, n => by
rw [ack_succ_succ]
cases' exists_eq_succ_of_ne_zero (ack_pos (m + 1) n).ne' with h h
rw [h]
apply one_lt_ack_succ_right
#align one_lt_ack_succ_right one_lt_ack_succ_right
theorem ack_strictMono_right : ∀ m, StrictMono (ack m)
| 0, n₁, n₂, h => by simpa using h
| m + 1, 0, n + 1, _h => by
rw [ack_succ_zero, ack_succ_succ]
exact ack_strictMono_right _ (one_lt_ack_succ_left m n)
| m + 1, n₁ + 1, n₂ + 1, h => by
rw [ack_succ_succ, ack_succ_succ]
apply ack_strictMono_right _ (ack_strictMono_right _ _)
rwa [add_lt_add_iff_right] at h
#align ack_strict_mono_right ack_strictMono_right
theorem ack_mono_right (m : ℕ) : Monotone (ack m) :=
(ack_strictMono_right m).monotone
#align ack_mono_right ack_mono_right
theorem ack_injective_right (m : ℕ) : Function.Injective (ack m) :=
(ack_strictMono_right m).injective
#align ack_injective_right ack_injective_right
@[simp]
theorem ack_lt_iff_right {m n₁ n₂ : ℕ} : ack m n₁ < ack m n₂ ↔ n₁ < n₂ :=
(ack_strictMono_right m).lt_iff_lt
#align ack_lt_iff_right ack_lt_iff_right
@[simp]
theorem ack_le_iff_right {m n₁ n₂ : ℕ} : ack m n₁ ≤ ack m n₂ ↔ n₁ ≤ n₂ :=
(ack_strictMono_right m).le_iff_le
#align ack_le_iff_right ack_le_iff_right
@[simp]
theorem ack_inj_right {m n₁ n₂ : ℕ} : ack m n₁ = ack m n₂ ↔ n₁ = n₂ :=
(ack_injective_right m).eq_iff
#align ack_inj_right ack_inj_right
theorem max_ack_right (m n₁ n₂ : ℕ) : ack m (max n₁ n₂) = max (ack m n₁) (ack m n₂) :=
(ack_mono_right m).map_max
#align max_ack_right max_ack_right
| Mathlib/Computability/Ackermann.lean | 175 | 185 | theorem add_lt_ack : ∀ m n, m + n < ack m n
| 0, n => by simp
| m + 1, 0 => by simpa using add_lt_ack m 1
| m + 1, n + 1 =>
calc
m + 1 + n + 1 ≤ m + (m + n + 2) := by | omega
_ < ack m (m + n + 2) := add_lt_ack _ _
_ ≤ ack m (ack (m + 1) n) :=
ack_mono_right m <| le_of_eq_of_le (by rw [succ_eq_add_one]; ring_nf)
<| succ_le_of_lt <| add_lt_ack (m + 1) n
_ = ack (m + 1) (n + 1) := (ack_succ_succ m n).symm
| 0 |
import Mathlib.Data.Multiset.Bind
import Mathlib.Control.Traversable.Lemmas
import Mathlib.Control.Traversable.Instances
#align_import data.multiset.functor from "leanprover-community/mathlib"@"1f0096e6caa61e9c849ec2adbd227e960e9dff58"
universe u
namespace Multiset
open List
instance functor : Functor Multiset where map := @map
@[simp]
theorem fmap_def {α' β'} {s : Multiset α'} (f : α' → β') : f <$> s = s.map f :=
rfl
#align multiset.fmap_def Multiset.fmap_def
instance : LawfulFunctor Multiset where
id_map := by simp
comp_map := by simp
map_const {_ _} := rfl
open LawfulTraversable CommApplicative
variable {F : Type u → Type u} [Applicative F] [CommApplicative F]
variable {α' β' : Type u} (f : α' → F β')
def traverse : Multiset α' → F (Multiset β') := by
refine Quotient.lift (Functor.map Coe.coe ∘ Traversable.traverse f) ?_
introv p; unfold Function.comp
induction p with
| nil => rfl
| @cons x l₁ l₂ _ h =>
have :
Multiset.cons <$> f x <*> Coe.coe <$> Traversable.traverse f l₁ =
Multiset.cons <$> f x <*> Coe.coe <$> Traversable.traverse f l₂ := by rw [h]
simpa [functor_norm] using this
| swap x y l =>
have :
(fun a b (l : List β') ↦ (↑(a :: b :: l) : Multiset β')) <$> f y <*> f x =
(fun a b l ↦ ↑(a :: b :: l)) <$> f x <*> f y := by
rw [CommApplicative.commutative_map]
congr
funext a b l
simpa [flip] using Perm.swap a b l
simp [(· ∘ ·), this, functor_norm, Coe.coe]
| trans => simp [*]
#align multiset.traverse Multiset.traverse
instance : Monad Multiset :=
{ Multiset.functor with
pure := fun x ↦ {x}
bind := @bind }
@[simp]
theorem pure_def {α} : (pure : α → Multiset α) = singleton :=
rfl
#align multiset.pure_def Multiset.pure_def
@[simp]
theorem bind_def {α β} : (· >>= ·) = @bind α β :=
rfl
#align multiset.bind_def Multiset.bind_def
instance : LawfulMonad Multiset := LawfulMonad.mk'
(bind_pure_comp := fun _ _ ↦ by simp only [pure_def, bind_def, bind_singleton, fmap_def])
(id_map := fun _ ↦ by simp only [fmap_def, id_eq, map_id'])
(pure_bind := fun _ _ ↦ by simp only [pure_def, bind_def, singleton_bind])
(bind_assoc := @bind_assoc)
open Functor
open Traversable LawfulTraversable
@[simp]
theorem lift_coe {α β : Type*} (x : List α) (f : List α → β)
(h : ∀ a b : List α, a ≈ b → f a = f b) : Quotient.lift f h (x : Multiset α) = f x :=
Quotient.lift_mk _ _ _
#align multiset.lift_coe Multiset.lift_coe
@[simp]
theorem map_comp_coe {α β} (h : α → β) :
Functor.map h ∘ Coe.coe = (Coe.coe ∘ Functor.map h : List α → Multiset β) := by
funext; simp only [Function.comp_apply, Coe.coe, fmap_def, map_coe, List.map_eq_map]
#align multiset.map_comp_coe Multiset.map_comp_coe
theorem id_traverse {α : Type*} (x : Multiset α) : traverse (pure : α → Id α) x = x := by
refine Quotient.inductionOn x ?_
intro
simp [traverse, Coe.coe]
#align multiset.id_traverse Multiset.id_traverse
| Mathlib/Data/Multiset/Functor.lean | 108 | 116 | theorem comp_traverse {G H : Type _ → Type _} [Applicative G] [Applicative H] [CommApplicative G]
[CommApplicative H] {α β γ : Type _} (g : α → G β) (h : β → H γ) (x : Multiset α) :
traverse (Comp.mk ∘ Functor.map h ∘ g) x =
Comp.mk (Functor.map (traverse h) (traverse g x)) := by |
refine Quotient.inductionOn x ?_
intro
simp only [traverse, quot_mk_to_coe, lift_coe, Coe.coe, Function.comp_apply, Functor.map_map,
functor_norm]
simp only [Function.comp, lift_coe]
| 0 |
import Mathlib.Analysis.Complex.CauchyIntegral
import Mathlib.Analysis.Calculus.FDeriv.Analytic
import Mathlib.Analysis.NormedSpace.Completion
#align_import analysis.complex.liouville from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open TopologicalSpace Metric Set Filter Asymptotics Function MeasureTheory Bornology
open scoped Topology Filter NNReal Real
universe u v
variable {E : Type u} [NormedAddCommGroup E] [NormedSpace ℂ E] {F : Type v} [NormedAddCommGroup F]
[NormedSpace ℂ F]
local postfix:100 "̂" => UniformSpace.Completion
namespace Complex
theorem deriv_eq_smul_circleIntegral [CompleteSpace F] {R : ℝ} {c : ℂ} {f : ℂ → F} (hR : 0 < R)
(hf : DiffContOnCl ℂ f (ball c R)) :
deriv f c = (2 * π * I : ℂ)⁻¹ • ∮ z in C(c, R), (z - c) ^ (-2 : ℤ) • f z := by
lift R to ℝ≥0 using hR.le
refine (hf.hasFPowerSeriesOnBall hR).hasFPowerSeriesAt.deriv.trans ?_
simp only [cauchyPowerSeries_apply, one_div, zpow_neg, pow_one, smul_smul, zpow_two, mul_inv]
#align complex.deriv_eq_smul_circle_integral Complex.deriv_eq_smul_circleIntegral
theorem norm_deriv_le_aux [CompleteSpace F] {c : ℂ} {R C : ℝ} {f : ℂ → F} (hR : 0 < R)
(hf : DiffContOnCl ℂ f (ball c R)) (hC : ∀ z ∈ sphere c R, ‖f z‖ ≤ C) :
‖deriv f c‖ ≤ C / R := by
have : ∀ z ∈ sphere c R, ‖(z - c) ^ (-2 : ℤ) • f z‖ ≤ C / (R * R) :=
fun z (hz : abs (z - c) = R) => by
simpa [-mul_inv_rev, norm_smul, hz, zpow_two, ← div_eq_inv_mul] using
(div_le_div_right (mul_pos hR hR)).2 (hC z hz)
calc
‖deriv f c‖ = ‖(2 * π * I : ℂ)⁻¹ • ∮ z in C(c, R), (z - c) ^ (-2 : ℤ) • f z‖ :=
congr_arg norm (deriv_eq_smul_circleIntegral hR hf)
_ ≤ R * (C / (R * R)) :=
(circleIntegral.norm_two_pi_i_inv_smul_integral_le_of_norm_le_const hR.le this)
_ = C / R := by rw [mul_div_left_comm, div_self_mul_self', div_eq_mul_inv]
#align complex.norm_deriv_le_aux Complex.norm_deriv_le_aux
theorem norm_deriv_le_of_forall_mem_sphere_norm_le {c : ℂ} {R C : ℝ} {f : ℂ → F} (hR : 0 < R)
(hd : DiffContOnCl ℂ f (ball c R)) (hC : ∀ z ∈ sphere c R, ‖f z‖ ≤ C) :
‖deriv f c‖ ≤ C / R := by
set e : F →L[ℂ] F̂ := UniformSpace.Completion.toComplL
have : HasDerivAt (e ∘ f) (e (deriv f c)) c :=
e.hasFDerivAt.comp_hasDerivAt c
(hd.differentiableAt isOpen_ball <| mem_ball_self hR).hasDerivAt
calc
‖deriv f c‖ = ‖deriv (e ∘ f) c‖ := by
rw [this.deriv]
exact (UniformSpace.Completion.norm_coe _).symm
_ ≤ C / R :=
norm_deriv_le_aux hR (e.differentiable.comp_diffContOnCl hd) fun z hz =>
(UniformSpace.Completion.norm_coe _).trans_le (hC z hz)
#align complex.norm_deriv_le_of_forall_mem_sphere_norm_le Complex.norm_deriv_le_of_forall_mem_sphere_norm_le
| Mathlib/Analysis/Complex/Liouville.lean | 88 | 101 | theorem liouville_theorem_aux {f : ℂ → F} (hf : Differentiable ℂ f) (hb : IsBounded (range f))
(z w : ℂ) : f z = f w := by |
suffices ∀ c, deriv f c = 0 from is_const_of_deriv_eq_zero hf this z w
clear z w; intro c
obtain ⟨C, C₀, hC⟩ : ∃ C > (0 : ℝ), ∀ z, ‖f z‖ ≤ C := by
rcases isBounded_iff_forall_norm_le.1 hb with ⟨C, hC⟩
exact
⟨max C 1, lt_max_iff.2 (Or.inr zero_lt_one), fun z =>
(hC (f z) (mem_range_self _)).trans (le_max_left _ _)⟩
refine norm_le_zero_iff.1 (le_of_forall_le_of_dense fun ε ε₀ => ?_)
calc
‖deriv f c‖ ≤ C / (C / ε) :=
norm_deriv_le_of_forall_mem_sphere_norm_le (div_pos C₀ ε₀) hf.diffContOnCl fun z _ => hC z
_ = ε := div_div_cancel' C₀.lt.ne'
| 0 |
import Mathlib.Analysis.Convex.Combination
import Mathlib.Analysis.Convex.Extreme
#align_import analysis.convex.independent from "leanprover-community/mathlib"@"fefd8a38be7811574cd2ec2f77d3a393a407f112"
open scoped Classical
open Affine
open Finset Function
variable {𝕜 E ι : Type*}
section OrderedSemiring
variable (𝕜) [OrderedSemiring 𝕜] [AddCommGroup E] [Module 𝕜 E] {s t : Set E}
def ConvexIndependent (p : ι → E) : Prop :=
∀ (s : Set ι) (x : ι), p x ∈ convexHull 𝕜 (p '' s) → x ∈ s
#align convex_independent ConvexIndependent
variable {𝕜}
theorem Subsingleton.convexIndependent [Subsingleton ι] (p : ι → E) : ConvexIndependent 𝕜 p := by
intro s x hx
have : (convexHull 𝕜 (p '' s)).Nonempty := ⟨p x, hx⟩
rw [convexHull_nonempty_iff, Set.image_nonempty] at this
rwa [Subsingleton.mem_iff_nonempty]
#align subsingleton.convex_independent Subsingleton.convexIndependent
protected theorem ConvexIndependent.injective {p : ι → E} (hc : ConvexIndependent 𝕜 p) :
Function.Injective p := by
refine fun i j hij => hc {j} i ?_
rw [hij, Set.image_singleton, convexHull_singleton]
exact Set.mem_singleton _
#align convex_independent.injective ConvexIndependent.injective
theorem ConvexIndependent.comp_embedding {ι' : Type*} (f : ι' ↪ ι) {p : ι → E}
(hc : ConvexIndependent 𝕜 p) : ConvexIndependent 𝕜 (p ∘ f) := by
intro s x hx
rw [← f.injective.mem_set_image]
exact hc _ _ (by rwa [Set.image_image])
#align convex_independent.comp_embedding ConvexIndependent.comp_embedding
protected theorem ConvexIndependent.subtype {p : ι → E} (hc : ConvexIndependent 𝕜 p) (s : Set ι) :
ConvexIndependent 𝕜 fun i : s => p i :=
hc.comp_embedding (Embedding.subtype _)
#align convex_independent.subtype ConvexIndependent.subtype
protected theorem ConvexIndependent.range {p : ι → E} (hc : ConvexIndependent 𝕜 p) :
ConvexIndependent 𝕜 ((↑) : Set.range p → E) := by
let f : Set.range p → ι := fun x => x.property.choose
have hf : ∀ x, p (f x) = x := fun x => x.property.choose_spec
let fe : Set.range p ↪ ι := ⟨f, fun x₁ x₂ he => Subtype.ext (hf x₁ ▸ hf x₂ ▸ he ▸ rfl)⟩
convert hc.comp_embedding fe
ext
rw [Embedding.coeFn_mk, comp_apply, hf]
#align convex_independent.range ConvexIndependent.range
protected theorem ConvexIndependent.mono {s t : Set E} (hc : ConvexIndependent 𝕜 ((↑) : t → E))
(hs : s ⊆ t) : ConvexIndependent 𝕜 ((↑) : s → E) :=
hc.comp_embedding (s.embeddingOfSubset t hs)
#align convex_independent.mono ConvexIndependent.mono
theorem Function.Injective.convexIndependent_iff_set {p : ι → E} (hi : Function.Injective p) :
ConvexIndependent 𝕜 ((↑) : Set.range p → E) ↔ ConvexIndependent 𝕜 p :=
⟨fun hc =>
hc.comp_embedding
(⟨fun i => ⟨p i, Set.mem_range_self _⟩, fun _ _ h => hi (Subtype.mk_eq_mk.1 h)⟩ :
ι ↪ Set.range p),
ConvexIndependent.range⟩
#align function.injective.convex_independent_iff_set Function.Injective.convexIndependent_iff_set
@[simp]
protected theorem ConvexIndependent.mem_convexHull_iff {p : ι → E} (hc : ConvexIndependent 𝕜 p)
(s : Set ι) (i : ι) : p i ∈ convexHull 𝕜 (p '' s) ↔ i ∈ s :=
⟨hc _ _, fun hi => subset_convexHull 𝕜 _ (Set.mem_image_of_mem p hi)⟩
#align convex_independent.mem_convex_hull_iff ConvexIndependent.mem_convexHull_iff
theorem convexIndependent_iff_not_mem_convexHull_diff {p : ι → E} :
ConvexIndependent 𝕜 p ↔ ∀ i s, p i ∉ convexHull 𝕜 (p '' (s \ {i})) := by
refine ⟨fun hc i s h => ?_, fun h s i hi => ?_⟩
· rw [hc.mem_convexHull_iff] at h
exact h.2 (Set.mem_singleton _)
· by_contra H
refine h i s ?_
rw [Set.diff_singleton_eq_self H]
exact hi
#align convex_independent_iff_not_mem_convex_hull_diff convexIndependent_iff_not_mem_convexHull_diff
theorem convexIndependent_set_iff_inter_convexHull_subset {s : Set E} :
ConvexIndependent 𝕜 ((↑) : s → E) ↔ ∀ t, t ⊆ s → s ∩ convexHull 𝕜 t ⊆ t := by
constructor
· rintro hc t h x ⟨hxs, hxt⟩
refine hc { x | ↑x ∈ t } ⟨x, hxs⟩ ?_
rw [Subtype.coe_image_of_subset h]
exact hxt
· intro hc t x h
rw [← Subtype.coe_injective.mem_set_image]
exact hc (t.image ((↑) : s → E)) (Subtype.coe_image_subset s t) ⟨x.prop, h⟩
#align convex_independent_set_iff_inter_convex_hull_subset convexIndependent_set_iff_inter_convexHull_subset
| Mathlib/Analysis/Convex/Independent.lean | 158 | 166 | theorem convexIndependent_set_iff_not_mem_convexHull_diff {s : Set E} :
ConvexIndependent 𝕜 ((↑) : s → E) ↔ ∀ x ∈ s, x ∉ convexHull 𝕜 (s \ {x}) := by |
rw [convexIndependent_set_iff_inter_convexHull_subset]
constructor
· rintro hs x hxs hx
exact (hs _ Set.diff_subset ⟨hxs, hx⟩).2 (Set.mem_singleton _)
· rintro hs t ht x ⟨hxs, hxt⟩
by_contra h
exact hs _ hxs (convexHull_mono (Set.subset_diff_singleton ht h) hxt)
| 0 |
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