mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.LinearAlgebra.TensorProduct.Graded.Internal

Goal state before:
pp: R : Type u_1
ι : Type u_2
A : Type u_3
B : Type u_4
inst✝¹¹ : CommSemiring ι
inst✝¹⁰ : DecidableEq ι
inst✝⁹ : CommRing R
inst✝⁸ : Ring A
inst✝⁷ : Ring B
inst✝⁶ : Algebra R A
inst✝⁵ : Algebra R B
𝒜 : ι → Submodule R A
ℬ : ι → Submodule R B
inst✝⁴ : GradedAlgebra 𝒜
inst✝³ : GradedAlgebra ℬ
inst✝² : Module ι (Additive ℤˣ)
C : Type ?u.46
inst✝¹ : Ring C
inst✝ : Algebra R C
x y : 𝒜 ᵍ⊗[R] ℬ
⊢ (auxEquiv R ℬ 𝒜).symm
      (((gradedMul R (fun i ↦ ↥(ℬ i)) fun i ↦ ↥(𝒜 i))
          ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) x)))
        ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) y))) =
    (auxEquiv R ℬ 𝒜).symm ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) x)) *
      (auxEquiv R ℬ 𝒜).symm ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) y))

Tactic:
LinearEquiv.symm_apply_eq,

Goal state after:
R : Type u_1
ι : Type u_2
A : Type u_3
B : Type u_4
inst✝¹¹ : CommSemiring ι
inst✝¹⁰ : DecidableEq ι
inst✝⁹ : CommRing R
inst✝⁸ : Ring A
inst✝⁷ : Ring B
inst✝⁶ : Algebra R A
inst✝⁵ : Algebra R B
𝒜 : ι → Submodule R A
ℬ : ι → Submodule R B
inst✝⁴ : GradedAlgebra 𝒜
inst✝³ : GradedAlgebra ℬ
inst✝² : Module ι (Additive ℤˣ)
C : Type ?u.46
inst✝¹ : Ring C
inst✝ : Algebra R C
x y : 𝒜 ᵍ⊗[R] ℬ
⊢ ((gradedMul R (fun i ↦ ↥(ℬ i)) fun i ↦ ↥(𝒜 i)) ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) x)))
      ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) y)) =
    (auxEquiv R ℬ 𝒜)
      ((auxEquiv R ℬ 𝒜).symm ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) x)) *
        (auxEquiv R ℬ 𝒜).symm ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) y)))
Module: Mathlib.LinearAlgebra.TensorProduct.Graded.Internal

Goal state before:
pp: R : Type u_1
ι : Type u_2
A : Type u_3
B : Type u_4
inst✝¹¹ : CommSemiring ι
inst✝¹⁰ : DecidableEq ι
inst✝⁹ : CommRing R
inst✝⁸ : Ring A
inst✝⁷ : Ring B
inst✝⁶ : Algebra R A
inst✝⁵ : Algebra R B
𝒜 : ι → Submodule R A
ℬ : ι → Submodule R B
inst✝⁴ : GradedAlgebra 𝒜
inst✝³ : GradedAlgebra ℬ
inst✝² : Module ι (Additive ℤˣ)
C : Type ?u.46
inst✝¹ : Ring C
inst✝ : Algebra R C
x y : 𝒜 ᵍ⊗[R] ℬ
⊢ (auxEquiv R ℬ 𝒜).symm ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) (x * y))) =
    (auxEquiv R ℬ 𝒜).symm ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) x)) *
      (auxEquiv R ℬ 𝒜).symm ((gradedComm R (fun i ↦ ↥(𝒜 i)) fun i ↦ ↥(ℬ i)) ((auxEquiv R 𝒜 ℬ) y))

Tactic:
simp_rw [auxEquiv_mul, gradedComm_gradedMul, LinearEquiv.symm_apply_eq,
        ← gradedComm_gradedMul, auxEquiv_mul, LinearEquiv.apply_symm_apply, gradedComm_gradedMul]

Goal state after:
Module: Mathlib.LinearAlgebra.LinearIndependent.BaseChange

Goal state before:
pp: ι : Type u_1
ι' : Type u_2
inst✝³ : Finite ι'
K : Type u_3
L : Type u_4
inst✝² : Field K
inst✝¹ : Field L
inst✝ : Algebra K L
v : ι → ι' → K
hv : LinearIndependent K v
⊢ LinearIndependent L fun i ↦ ⇑(algebraMap K L) ∘ v i

Tactic:
by
  classical
  let : Fintype ι' := .ofFinite ι'
  let I : Set (ι' → K) := hv.linearIndepOn_id.extend (subset_univ _)
  let b : Module.Basis I K (ι' → K) := .extend hv.linearIndepOn_id
  let b' : Module.Basis I L (ι' → L) := (b.baseChange L).map (TensorProduct.piScalarRight K L L ι')
  let v' (i : ι) : I := ⟨v i, hv.linearIndepOn_id.subset_extend _ <| mem_range_self i⟩
  have hv' : b' ∘ v' = fun i ↦ algebraMap K L ∘ v i := by
    ext; simp [b', b, v', Module.Basis.extend, Algebra.algebraMap_eq_smul_one]
  have h_inj : Injective v' := fun i j hij ↦ by have : Injective v := hv.injective; aesop
  rw [← hv']
  exact b'.linearIndependent.comp _ h_inj

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.Gershgorin

Goal state before:
pp: K : Type u_1
n : Type u_2
inst✝² : NormedField K
inst✝¹ : Fintype n
inst✝ : DecidableEq n
A : Matrix n n K
μ : K
hμ : Module.End.HasEigenvalue (Matrix.toLin' A) μ
h✝ : Nonempty n
v : n → K
h_eg : v ∈ (Module.End.genEigenspace (Matrix.toLin' A) μ) 1
h_nz✝ : v ≠ 0
i : n
h_i : (Finset.univ.sup' ⋯ fun i ↦ ‖v i‖) = ‖v i‖
h_nz : v i ≠ 0
h_le : ∀ (j : n), ‖v j * (v i)⁻¹‖ ≤ 1
⊢ A i i - μ = (A i i * v i - μ * v i) * (v i)⁻¹

Tactic:
field

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.IsDiag

Goal state before:
pp: α : Type u_1
n : Type u_4
inst✝ : AddZeroClass α
A B : Matrix n n α
ha : A.IsDiag
hb : B.IsDiag
⊢ (A + B).IsDiag

Tactic:
intro i j h
  simp [ha h, hb h]

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.IsDiag

Goal state before:
pp: α : Type u_1
n : Type u_4
inst✝ : SubtractionMonoid α
A B : Matrix n n α
ha : A.IsDiag
hb : B.IsDiag
⊢ (A - B).IsDiag

Tactic:
intro i j h
  simp [ha h, hb h]

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.FixedDetMatrices

Goal state before:
pp: A : SL(2, ℤ)
⊢ A ∈ closure {S, T}

Tactic:
induction A using (induction_on one_ne_zero) with

Goal state after:
Module: Mathlib.RingTheory.PiTensorProduct

Goal state before:
pp: ι : Type u_1
R' : Type u_2
R : Type u_3
A : ι → Type u_4
inst✝⁷ : CommSemiring R'
inst✝⁶ : CommSemiring R
inst✝⁵ : (i : ι) → Semiring (A i)
inst✝⁴ : Algebra R' R
inst✝³ : (i : ι) → Algebra R (A i)
inst✝² : (i : ι) → Algebra R' (A i)
inst✝¹ : ∀ (i : ι), IsScalarTower R' R (A i)
r : R'
i : ι
inst✝ : DecidableEq ι
⊢ r • (tprod R) 1 = (tprod R) (Pi.mulSingle i ((algebraMap R' (A i)) r))

Tactic:
have : Pi.mulSingle i (algebraMap R' (A i) r) = update (fun i ↦ 1) i (r • 1) := by
    rw [Algebra.algebraMap_eq_smul_one]; rfl

Goal state after:
ι : Type u_1
R' : Type u_2
R : Type u_3
A : ι → Type u_4
inst✝⁷ : CommSemiring R'
inst✝⁶ : CommSemiring R
inst✝⁵ : (i : ι) → Semiring (A i)
inst✝⁴ : Algebra R' R
inst✝³ : (i : ι) → Algebra R (A i)
inst✝² : (i : ι) → Algebra R' (A i)
inst✝¹ : ∀ (i : ι), IsScalarTower R' R (A i)
r : R'
i : ι
inst✝ : DecidableEq ι
this : Pi.mulSingle i ((algebraMap R' (A i)) r) = update (fun i ↦ 1) i (r • 1)
⊢ r • (tprod R) 1 = (tprod R) (Pi.mulSingle i ((algebraMap R' (A i)) r))
Module: Mathlib.LinearAlgebra.Projectivization.Collinear

Goal state before:
pp: K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
a b : ℙ K V
h : a = b
⊢ IsCollinear {a, b}

Tactic:
then

Goal state after:
K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
a b : ℙ K V
h : a = b
⊢ IsCollinear {a, b}
Module: Mathlib.LinearAlgebra.Projectivization.PSL.PSL2

Goal state before:
pp: case «0».«1»
F : Type u_2
inst✝ : Field F
c : F
hij : (fun i ↦ i) ⟨0, ⋯⟩ ≠ (fun i ↦ i) ⟨1, ⋯⟩
⊢ SpecialLinearGroup.transvection hij c ∈ lineStab (F ∙ Pi.single 0 1) ⊔ lineStab (F ∙ Pi.single 1 1)

Tactic:
exact Subgroup.mem_sup_left <| transvection_mem_lineStab zero_ne_one c

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Lemmas

Goal state before:
pp: case inl
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁸ : CommRing R
inst✝⁷ : CharZero R
inst✝⁶ : IsDomain R
inst✝⁵ : AddCommGroup M
inst✝⁴ : Module R M
inst✝³ : AddCommGroup N
inst✝² : Module R N
P : RootPairing ι R M N
inst✝¹ : Finite ι
inst✝ : P.IsCrystallographic
b : P.Base
i j k : ι
hij : i ≠ j
hi : i ∈ b.support
hj : j ∈ b.support
hk : P.root k + P.root i - P.root j ∈ range ⇑P.root
hkj : k ≠ j
hk' : P.root k + P.root i ∈ range ⇑P.root
hm : 0 < P.pairingIn ℤ j k
⊢ P.root k - P.root j ∈ range ⇑P.root

Tactic:
rw [← neg_mem_range_root_iff, neg_sub]
    exact P.root_sub_root_mem_of_pairingIn_pos hm hkj.symm

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Basic

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommRing R
inst✝⁹ : AddCommGroup M
inst✝⁸ : Module R M
inst✝⁷ : AddCommGroup N
inst✝⁶ : Module R N
P : RootPairing ι R M N
inst✝⁵ : P.IsCrystallographic
b : P.Base
inst✝⁴ : Finite ι
inst✝³ : IsDomain R
inst✝² : CharZero R
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
x : Matrix (↥b.support ⊕ ι) (↥b.support ⊕ ι) R
hx : x ∈ lieAlgebra b
⊢ (ωConj b) x ∈ lieAlgebra b

Tactic:
induction hx using LieSubalgebra.lieSpan_induction with
  | mem u hu =>
    obtain (⟨i, rfl⟩ | ⟨i, rfl⟩ | ⟨i, rfl⟩) : (∃ j, h j = u) ∨ (∃ j, e j = u) ∨ (∃ j, f j = u) := by
      simpa only [mem_union, mem_range, or_assoc] using hu
    · rw [← neg_mem_iff]
      exact LieSubalgebra.subset_lieSpan <| by simp [ω_mul_h, mul_assoc]
    · exact LieSubalgebra.subset_lieSpan <| by simp [ω_mul_e, mul_assoc]
    · exact LieSubalgebra.subset_lieSpan <| by simp [ω_mul_f, mul_assoc]
  | zero => simp
  | add u v _ _ hu hv => simpa [mul_add, add_mul] using add_mem hu hv
  | smul t u _ hu => simpa using SMulMemClass.smul_mem _ hu
  | lie u v _ _ hu hv =>
    rw [LieEquiv.map_lie]
    exact (lieAlgebra b).lie_mem hu hv

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Semisimple

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommRing R
inst✝⁹ : IsDomain R
inst✝⁸ : CharZero R
inst✝⁷ : AddCommGroup M
inst✝⁶ : Module R M
inst✝⁵ : AddCommGroup N
inst✝⁴ : Module R N
P : RootPairing ι R M N
inst✝³ : P.IsCrystallographic
inst✝² : P.IsReduced
b : P.Base
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
i : ↥b.support
n : ℕ
hn : e i ^ n = 0
this : ω b * f i ^ n = 0
⊢ f i ^ n = 0

Tactic:
by simpa [← mul_assoc] using congr_arg (ω b * ·) this

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Relations

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁹ : Finite ι
inst✝⁸ : CommRing R
inst✝⁷ : IsDomain R
inst✝⁶ : CharZero R
inst✝⁵ : AddCommGroup M
inst✝⁴ : Module R M
inst✝³ : AddCommGroup N
inst✝² : Module R N
P : RootPairing ι R M N
inst✝¹ : P.IsCrystallographic
b : P.Base
inst✝ : Fintype ι
i j k : ↥b.support
l : ι
this : InvolutiveNeg ι := P.indexNeg
hl : P.root ↑j = P.root ↑i + P.root l
⊢ P.root (-l) = P.root ↑i - P.root ↑j

Tactic:
by simp [hl]

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Relations

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁹ : Finite ι
inst✝⁸ : CommRing R
inst✝⁷ : IsDomain R
inst✝⁶ : CharZero R
inst✝⁵ : AddCommGroup M
inst✝⁴ : Module R M
inst✝³ : AddCommGroup N
inst✝² : Module R N
P : RootPairing ι R M N
inst✝¹ : P.IsCrystallographic
b : P.Base
inst✝ : Fintype ι
i j k : ↥b.support
l : ι
this : InvolutiveNeg ι := P.indexNeg
aux₁ : ∀ x ∈ Finset.univ, ¬(P.root x = P.root ↑i + P.root l ∧ k = j ∧ x = ↑j)
hl : P.root ↑i = P.root ↑j - P.root l
⊢ P.root (-l) = P.root ↑i - P.root ↑j

Tactic:
by simp [hl]

Goal state after:
Module: Mathlib.LinearAlgebra.SModEq.Pow

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
I : Ideal R
p : ℕ
hpI : ↑p ∈ I
x y : R
h : x ≡ y [SMOD I]
m : ℕ
⊢ x ^ p ^ m ≡ y ^ p ^ m [SMOD I ^ (m + 1)]

Tactic:
induction m with

Goal state after:
Module: Mathlib.LinearAlgebra.SesquilinearForm.Star

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝³ : CommSemiring R
inst✝² : StarRing R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
B : M →ₗ⋆[R] M →ₗ[R] R
ι : Type u_4
b : Basis ι R M
⊢ (∀ (i j : ι), star ((B (b i)) (b j)) = (B (b j)) (b i)) → B.IsSymm

Tactic:
refine fun h ↦ ⟨fun x y ↦ ?_⟩

Goal state after:
R : Type u_1
M : Type u_2
inst✝³ : CommSemiring R
inst✝² : StarRing R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
B : M →ₗ⋆[R] M →ₗ[R] R
ι : Type u_4
b : Basis ι R M
h : ∀ (i j : ι), star ((B (b i)) (b j)) = (B (b j)) (b i)
x y : M
⊢ (starRingEnd R) ((B x) y) = (B y) x
Module: Mathlib.LinearAlgebra.SymmetricAlgebra.Basic

Goal state before:
pp: case algebraMap
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
a : SymmetricAlgebra R M
r : R
⊢ Commute a ((algebraMap R (SymmetricAlgebra R M)) r)

Tactic:
exact Algebra.commute_algebraMap_right _ _

Goal state after:
Module: Mathlib.Logic.Godel.GodelBetaFunction

Goal state before:
pp: case inl
n m a : ℕ
ha : m - n ∣ a
p : ℕ
pp : Prime p
hn : p ∣ n * a + 1
hm : p ∣ m * a + 1
this : p ∣ (m - n) * a
hp : p ∣ m - n
⊢ p ∣ a

pp: case inr
n m a : ℕ
ha : m - n ∣ a
p : ℕ
pp : Prime p
hn : p ∣ n * a + 1
hm : p ∣ m * a + 1
this : p ∣ (m - n) * a
hp : p ∣ a
⊢ p ∣ a

Tactic:
· exact Nat.dvd_trans hp ha

Goal state after:
case inr
n m a : ℕ
ha : m - n ∣ a
p : ℕ
pp : Prime p
hn : p ∣ n * a + 1
hm : p ∣ m * a + 1
this : p ∣ (m - n) * a
hp : p ∣ a
⊢ p ∣ a
Module: Mathlib.Logic.Hydra

Goal state before:
pp: case refine_2
α : Type u_1
r : α → α → Prop
inst✝¹ : DecidableEq α
inst✝ : Std.Irrefl r
s t u : Multiset α
a : α
he : s + {a} = t + u
hr : ∀ (a' : α), ¬r a' a → a' ∉ u
⊢ count a s < count a t

Tactic:
apply_fun count a at he

Goal state after:
case refine_2
α : Type u_1
r : α → α → Prop
inst✝¹ : DecidableEq α
inst✝ : Std.Irrefl r
s t u : Multiset α
a : α
hr : ∀ (a' : α), ¬r a' a → a' ∉ u
he : count a (s + {a}) = count a (t + u)
⊢ count a s < count a t
Module: Mathlib.LinearAlgebra.Transvection.Generation

Goal state before:
pp: case hfv'
K : Type u_1
inst✝³ : DivisionRing K
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Module.Finite K V
e : V ≃ₗ[K] V
f : Dual K V
u : V
hf : (↑e).fixedSubmodule ⊔ K ∙ (e u - u) ≤ ker f
hfu : f u = 1
⊢ e u - u ∈ ker f

Tactic:
refine hf (mem_sup_right ?_)

Goal state after:
case hfv'
K : Type u_1
inst✝³ : DivisionRing K
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Module.Finite K V
e : V ≃ₗ[K] V
f : Dual K V
u : V
hf : (↑e).fixedSubmodule ⊔ K ∙ (e u - u) ≤ ker f
hfu : f u = 1
⊢ e u - u ∈ K ∙ (e u - u)
Module: Mathlib.LinearAlgebra.Transvection.Generation

Goal state before:
pp: K : Type u_1
inst✝³ : DivisionRing K
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Module.Finite K V
n✝ : ℕ
e : V ≃ₗ[K] V
he : e.fixedReduce = 1
n : ℕ
h : finrank K (V ⧸ (↑e).fixedSubmodule) = n + 2
hind :
  ∀ {e : V ≃ₗ[K] V},
    e.fixedReduce = 1 → finrank K (V ⧸ (↑e).fixedSubmodule) = n + 1 → e ∈ transvections K V ^ n * dilatransvections K V
u : V
hu : u ∉ (↑e).fixedSubmodule
f : Dual K V
hfu : f u ≠ 0
hf : map f (↑e).fixedSubmodule = ⊥
v : V := (f u)⁻¹ • u
⊢ ∃ f v, (↑e).fixedSubmodule ≤ ker f ∧ f v = 1

Tactic:
have hv : f v = 1 := by simp [v, inv_mul_cancel₀ hfu]

Goal state after:
K : Type u_1
inst✝³ : DivisionRing K
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Module.Finite K V
n✝ : ℕ
e : V ≃ₗ[K] V
he : e.fixedReduce = 1
n : ℕ
h : finrank K (V ⧸ (↑e).fixedSubmodule) = n + 2
hind :
  ∀ {e : V ≃ₗ[K] V},
    e.fixedReduce = 1 → finrank K (V ⧸ (↑e).fixedSubmodule) = n + 1 → e ∈ transvections K V ^ n * dilatransvections K V
u : V
hu : u ∉ (↑e).fixedSubmodule
f : Dual K V
hfu : f u ≠ 0
hf : map f (↑e).fixedSubmodule = ⊥
v : V := (f u)⁻¹ • u
hv : f v = 1
⊢ ∃ f v, (↑e).fixedSubmodule ≤ ker f ∧ f v = 1
Module: Mathlib.MeasureTheory.Constructions.Projective

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
inst✝¹ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
μ ν : Measure ((i : ι) → α i)
inst✝ : ∀ (i : Finset ι), IsFiniteMeasure (P i)
hμ : IsProjectiveLimit μ P
hν : IsProjectiveLimit ν P
this : IsFiniteMeasure μ
s : Set ((i : ι) → α i)
hs : s ∈ measurableCylinders α
⊢ μ s = ν s

Tactic:
obtain ⟨I, S, hS, rfl⟩ := (mem_measurableCylinders _).mp hs

Goal state after:
ι : Type u_1
α : ι → Type u_2
inst✝¹ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
μ ν : Measure ((i : ι) → α i)
inst✝ : ∀ (i : Finset ι), IsFiniteMeasure (P i)
hμ : IsProjectiveLimit μ P
hν : IsProjectiveLimit ν P
this : IsFiniteMeasure μ
I : Finset ι
S : Set ((i : ↥I) → α ↑i)
hS : MeasurableSet S
hs : cylinder I S ∈ measurableCylinders α
⊢ μ (cylinder I S) = ν (cylinder I S)
Module: Mathlib.MeasureTheory.SetSemiring

Goal state before:
pp: α : Type u_1
C : Set (Set α)
s t : Set α
hC : IsSetRing C
hs : s ∈ C
ht : t ∈ C
⊢ s ∩ t ∈ C

Tactic:
rw [← sdiff_sdiff_right_self]

Goal state after:
α : Type u_1
C : Set (Set α)
s t : Set α
hC : IsSetRing C
hs : s ∈ C
ht : t ∈ C
⊢ s \ (s \ t) ∈ C
Module: Mathlib.MeasureTheory.SetSemiring

Goal state before:
pp: case succ
α : Type u_1
C : Set (Set α)
hC : IsSetRing C
s : ℕ → Set α
hs : ∀ (n : ℕ), s n ∈ C
n : ℕ
hn : ⋂ i, ⋂ (_ : i ≤ n), s i ∈ C
⊢ (⋂ k, ⋂ (_ : k ≤ n), s k) ∩ s (n + 1) ∈ C

Tactic:
exact hC.inter_mem hn (hs _)

Goal state after:
Module: Mathlib.MeasureTheory.Constructions.Cylinders

Goal state before:
pp: case refine_1
ι : Type u_2
α : ι → Type u_1
inst✝ : (i : ι) → MeasurableSpace (α i)
s : Set ((i : ι) → α i)
hs : MeasurableSet s
⊢ ∀ t ∈ squareCylinders fun i ↦ {s | MeasurableSet s}, ∃ I t_1, I.Countable ∧ t = I.domRestrict ⁻¹' t_1

Tactic:
rintro - ⟨I, t, -, rfl⟩
    exact ⟨I, univ.pi (fun i ↦ t i), I.countable_toSet, by ext; simp⟩

Goal state after:
Module: Mathlib.MeasureTheory.Constructions.Cylinders

Goal state before:
pp: case refine_3
ι : Type u_2
α : ι → Type u_1
inst✝ : (i : ι) → MeasurableSpace (α i)
s : Set ((i : ι) → α i)
hs : MeasurableSet s
f : ℕ → Set ((a : ι) → α a)
⊢ Pairwise (Disjoint on f) →
    (∀ (i : ℕ), MeasurableSet (f i)) →
      (∀ (i : ℕ), ∃ I t, I.Countable ∧ f i = I.domRestrict ⁻¹' t) → ∃ I t, I.Countable ∧ ⋃ i, f i = I.domRestrict ⁻¹' t

Tactic:
df

Goal state after:
case refine_3
ι : Type u_2
α : ι → Type u_1
inst✝ : (i : ι) → MeasurableSpace (α i)
s : Set ((i : ι) → α i)
hs : MeasurableSet s
f : ℕ → Set ((a : ι) → α a)
df : Pairwise (Disjoint on f)
⊢ (∀ (i : ℕ), MeasurableSet (f i)) →
    (∀ (i : ℕ), ∃ I t, I.Countable ∧ f i = I.domRestrict ⁻¹' t) → ∃ I t, I.Countable ∧ ⋃ i, f i = I.domRestrict ⁻¹' t
Module: Mathlib.MeasureTheory.SetSemiring

Goal state before:
pp: α : Type u_1
C : Set (Set α)
J : Finset (Set α)
hC : IsSetSemiring C
hJ : ↑J ⊆ C
⊢ ⨆ x, disjointed (fun i ↦ ↑(J.equivFin.symm i)) (J.equivFin x) = J.sup id

Tactic:
J.equivFin.surjective.iSup_comp,

Goal state after:
α : Type u_1
C : Set (Set α)
J : Finset (Set α)
hC : IsSetSemiring C
hJ : ↑J ⊆ C
⊢ ⨆ y, disjointed (fun i ↦ ↑(J.equivFin.symm i)) y = J.sup id
Module: Mathlib.MeasureTheory.SetAlgebra

Goal state before:
pp: α : Type u_1
𝒜 : Set (Set α)
h : 𝒜.Countable
ℬ : Set (Set α) := {s | s ∈ 𝒜} ∪ {s | sᶜ ∈ 𝒜}
count_ℬ : ℬ.Countable
f : Set (Set (Set α)) → Set α := fun A ↦ ⋃ a ∈ A, ⋂ t ∈ a, t
𝒞 : Set (Set (Set α)) := {a | a.Finite ∧ a ⊆ ℬ}
count_𝒞 : 𝒞.Countable
𝒟 : Set (Set (Set (Set α))) := {A | A.Finite ∧ A ⊆ 𝒞}
count_𝒟 : 𝒟.Countable
s : Set α
⊢ s ∈ generateSetAlgebra 𝒜 → s ∈ f '' 𝒟

Tactic:
s_mem

Goal state after:
α : Type u_1
𝒜 : Set (Set α)
h : 𝒜.Countable
ℬ : Set (Set α) := {s | s ∈ 𝒜} ∪ {s | sᶜ ∈ 𝒜}
count_ℬ : ℬ.Countable
f : Set (Set (Set α)) → Set α := fun A ↦ ⋃ a ∈ A, ⋂ t ∈ a, t
𝒞 : Set (Set (Set α)) := {a | a.Finite ∧ a ⊆ ℬ}
count_𝒞 : 𝒞.Countable
𝒟 : Set (Set (Set (Set α))) := {A | A.Finite ∧ A ⊆ 𝒞}
count_𝒟 : 𝒟.Countable
s : Set α
s_mem : s ∈ generateSetAlgebra 𝒜
⊢ s ∈ f '' 𝒟
Module: Mathlib.MeasureTheory.Constructions.ProjectiveFamilyContent

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
mα : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
s t : Set ((i : ι) → α i)
hP : IsProjectiveMeasureFamily P
hs : s ∈ measurableCylinders α
ht : t ∈ measurableCylinders α
hst : Disjoint s t
I : Finset ι
S : Set ((i : ↥I) → α ↑i)
hS : MeasurableSet S
hs_eq : s = cylinder I S
J : Finset ι
T : Set ((i : ↥J) → α ↑i)
hT : MeasurableSet T
ht_eq : t = cylinder J T
S' : Set ((i : ↥(I ∪ J)) → α ↑i) := restrict₂ ⋯ ⁻¹' S
T' : Set ((i : ↥(I ∪ J)) → α ↑i) := restrict₂ ⋯ ⁻¹' T
hS' : MeasurableSet S'
hT' : MeasurableSet T'
h_eq1 : s = cylinder (I ∪ J) S'
⊢ t = cylinder (I ∪ J) T'

Tactic:
ht_eq

Goal state after:
ι : Type u_1
α : ι → Type u_2
mα : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
s t : Set ((i : ι) → α i)
hP : IsProjectiveMeasureFamily P
hs : s ∈ measurableCylinders α
ht : t ∈ measurableCylinders α
hst : Disjoint s t
I : Finset ι
S : Set ((i : ↥I) → α ↑i)
hS : MeasurableSet S
hs_eq : s = cylinder I S
J : Finset ι
T : Set ((i : ↥J) → α ↑i)
hT : MeasurableSet T
ht_eq : t = cylinder J T
S' : Set ((i : ↥(I ∪ J)) → α ↑i) := restrict₂ ⋯ ⁻¹' S
T' : Set ((i : ↥(I ∪ J)) → α ↑i) := restrict₂ ⋯ ⁻¹' T
hS' : MeasurableSet S'
hT' : MeasurableSet T'
h_eq1 : s = cylinder (I ∪ J) S'
⊢ cylinder J T = cylinder (I ∪ J) T'
Module: Mathlib.MeasureTheory.Constructions.ProjectiveFamilyContent

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
mα : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
s t : Set ((i : ι) → α i)
hP : IsProjectiveMeasureFamily P
hs : s ∈ measurableCylinders α
ht : t ∈ measurableCylinders α
hst : Disjoint s t
I : Finset ι
S : Set ((i : ↥I) → α ↑i)
hS : MeasurableSet S
hs_eq : s = cylinder I S
J : Finset ι
T : Set ((i : ↥J) → α ↑i)
hT : MeasurableSet T
ht_eq : t = cylinder J T
S' : Set ((i : ↥(I ∪ J)) → α ↑i) := restrict₂ ⋯ ⁻¹' S
T' : Set ((i : ↥(I ∪ J)) → α ↑i) := restrict₂ ⋯ ⁻¹' T
hS' : MeasurableSet S'
hT' : MeasurableSet T'
h_eq1 : s = cylinder (I ∪ J) S'
h_eq2 : t = cylinder (I ∪ J) T'
⊢ cylinder I S ∪ t = cylinder (I ∪ J) (S' ∪ T')

Tactic:
ht_eq

Goal state after:
ι : Type u_1
α : ι → Type u_2
mα : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
s t : Set ((i : ι) → α i)
hP : IsProjectiveMeasureFamily P
hs : s ∈ measurableCylinders α
ht : t ∈ measurableCylinders α
hst : Disjoint s t
I : Finset ι
S : Set ((i : ↥I) → α ↑i)
hS : MeasurableSet S
hs_eq : s = cylinder I S
J : Finset ι
T : Set ((i : ↥J) → α ↑i)
hT : MeasurableSet T
ht_eq : t = cylinder J T
S' : Set ((i : ↥(I ∪ J)) → α ↑i) := restrict₂ ⋯ ⁻¹' S
T' : Set ((i : ↥(I ∪ J)) → α ↑i) := restrict₂ ⋯ ⁻¹' T
hS' : MeasurableSet S'
hT' : MeasurableSet T'
h_eq1 : s = cylinder (I ∪ J) S'
h_eq2 : t = cylinder (I ∪ J) T'
⊢ cylinder I S ∪ cylinder J T = cylinder (I ∪ J) (S' ∪ T')
Module: Mathlib.MeasureTheory.Measure.AddContent

Goal state before:
pp: case refine_3
α : Type u_1
C : Set (Set α)
s t : Set α
G : Type u_2
inst✝² : AddCommMonoid G
m : AddContent G C
inst✝¹ : PartialOrder G
inst✝ : CanonicallyOrderedAdd G
hC : IsSetSemiring C
hs : s ∈ C
ht : t ∈ C
hst : s ⊆ t
⊢ ∀ s_1 ∈ {s}, s_1 ⊆ t

Tactic:
· simp [hst]

Goal state after:
Module: Mathlib.MeasureTheory.Measure.AddContent

Goal state before:
pp: α : Type u_1
C : Set (Set α)
m : AddContent ℝ≥0∞ C
hC : IsSetSemiring C
m_subadd :
  ∀ (f : ℕ → Set α), (∀ (i : ℕ), f i ∈ C) → ⋃ i, f i ∈ C → Pairwise (Disjoint on f) → m (⋃ i, f i) ≤ ∑' (i : ℕ), m (f i)
f : ℕ → Set α
hf : ∀ (i : ℕ), f i ∈ C
hf_Union : ⋃ i, f i ∈ C
hf_disj : Pairwise (Disjoint on f)
I : Finset ℕ
⊢ ∑ i ∈ I, m (f i) ≤ m (⋃ i, f i)

Tactic:
rw [← Finset.sum_image_of_disjoint addContent_empty (hf_disj.pairwiseDisjoint _)]

Goal state after:
α : Type u_1
C : Set (Set α)
m : AddContent ℝ≥0∞ C
hC : IsSetSemiring C
m_subadd :
  ∀ (f : ℕ → Set α), (∀ (i : ℕ), f i ∈ C) → ⋃ i, f i ∈ C → Pairwise (Disjoint on f) → m (⋃ i, f i) ≤ ∑' (i : ℕ), m (f i)
f : ℕ → Set α
hf : ∀ (i : ℕ), f i ∈ C
hf_Union : ⋃ i, f i ∈ C
hf_disj : Pairwise (Disjoint on f)
I : Finset ℕ
⊢ ∑ s ∈ Finset.image f I, m s ≤ m (⋃ i, f i)