mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.GroupTheory.Perm.ClosureSwap

Goal state before:
pp: case refine_2
α : Type u_2
inst✝ : DecidableEq α
S : Set (Equiv.Perm α)
hS : ∀ f ∈ S, f.IsSwap
supp : Set α
fin : supp.Finite
a : α
s : Set α
ih : ∀ {f : Equiv.Perm α}, (∀ (x : α), f x ∈ orbit (↥(closure S)) x) → (fixedBy α f)ᶜ ⊆ s → f ∈ closure S
f : Equiv.Perm α
hf : ∀ (x : α), f x ∈ orbit (↥(closure S)) x
supp_subset : (fixedBy α f)ᶜ ⊆ insert a s
b : α
hb : b ∉ s
⊢ b ∉ (fixedBy α (Equiv.swap (f a) a * f))ᶜ

Tactic:
simp_rw [notMem_compl_iff, mem_fixedBy, Perm.smul_def, Perm.mul_apply, swap_apply_def,
      apply_eq_iff_eq]

Goal state after:
case refine_2
α : Type u_2
inst✝ : DecidableEq α
S : Set (Equiv.Perm α)
hS : ∀ f ∈ S, f.IsSwap
supp : Set α
fin : supp.Finite
a : α
s : Set α
ih : ∀ {f : Equiv.Perm α}, (∀ (x : α), f x ∈ orbit (↥(closure S)) x) → (fixedBy α f)ᶜ ⊆ s → f ∈ closure S
f : Equiv.Perm α
hf : ∀ (x : α), f x ∈ orbit (↥(closure S)) x
supp_subset : (fixedBy α f)ᶜ ⊆ insert a s
b : α
hb : b ∉ s
⊢ (if b = a then a else if f b = a then f a else f b) = b
Module: Mathlib.GroupTheory.Perm.Centralizer

Goal state before:
pp: α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g : Perm α
a : g.Basis
c : ↥g.cycleFactorsFinset
τ✝ τ : ↥(range_toPermHom' g)
x : α
⊢ a.ofPermHomFun τ (a.ofPermHomFun τ⁻¹ x) = x

Tactic:
by rw [← ofPermHomFun_mul, mul_inv_cancel, ofPermHomFun_one]

Goal state after:
Module: Mathlib.GroupTheory.SpecificGroups.Alternating.Centralizer

Goal state before:
pp: case neg
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
m : Multiset ℕ
hm : ¬Even (m.sum + m.card)
⊢ map (Embedding.subtype fun x ↦ x ∈ alternatingGroup α) {g | (↑g).cycleType = m} = ∅

Tactic:
rw [Finset.eq_empty_iff_forall_notMem]

Goal state after:
case neg
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
m : Multiset ℕ
hm : ¬Even (m.sum + m.card)
⊢ ∀ (x : Perm α), x ∉ map (Embedding.subtype fun x ↦ x ∈ alternatingGroup α) {g | (↑g).cycleType = m}
Module: Mathlib.GroupTheory.PushoutI

Goal state before:
pp: ι : Type u_1
G : ι → Type u_2
H : Type u_3
K : Type u_4
inst✝² : Monoid K
inst✝¹ : (i : ι) → Monoid (G i)
inst✝ : Monoid H
φ : (i : ι) → H →* G i
x✝ : { f // ∀ (i : ι), (f.1 i).comp (φ i) = f.2 }
fst✝ : (i : ι) → G i →* K
snd✝ : H →* K
property✝ : ∀ (i : ι), ((fst✝, snd✝).1 i).comp (φ i) = (fst✝, snd✝).2
⊢ (fun f ↦ ⟨(fun i ↦ f.comp (of i), f.comp (base φ)), ⋯⟩) ((fun f ↦ lift (↑f).1 (↑f).2 ⋯) ⟨(fst✝, snd✝), property✝⟩) =
    ⟨(fst✝, snd✝), property✝⟩

Tactic:
by simp [DFunLike.ext_iff, funext_iff]

Goal state after:
Module: Mathlib.GroupTheory.PushoutI

Goal state before:
pp: case H.inl.mul
ι : Type u_1
G : ι → Type u_2
H : Type u_3
inst✝¹ : (i : ι) → Monoid (G i)
inst✝ : Monoid H
φ : (i : ι) → H →* G i
motive : (con φ).Quotient → Prop
of : ∀ (i : ι) (g : G i), motive (((con φ).mk'.comp (inl.comp CoprodI.of)) g)
base : ∀ (h : H), motive (((con φ).mk'.comp inr) h)
mul : ∀ (x y : (con φ).Quotient), motive x → motive y → motive (x * y)
x y : CoprodI G
ihx : motive ↑(inl x)
ihy : motive ↑(inl y)
⊢ motive ↑(inl (x * y))

Tactic:
rw [map_mul]

Goal state after:
case H.inl.mul
ι : Type u_1
G : ι → Type u_2
H : Type u_3
inst✝¹ : (i : ι) → Monoid (G i)
inst✝ : Monoid H
φ : (i : ι) → H →* G i
motive : (con φ).Quotient → Prop
of : ∀ (i : ι) (g : G i), motive (((con φ).mk'.comp (inl.comp CoprodI.of)) g)
base : ∀ (h : H), motive (((con φ).mk'.comp inr) h)
mul : ∀ (x y : (con φ).Quotient), motive x → motive y → motive (x * y)
x y : CoprodI G
ihx : motive ↑(inl x)
ihy : motive ↑(inl y)
⊢ motive ↑(inl x * inl y)
Module: Mathlib.GroupTheory.PushoutI

Goal state before:
pp: ι : Type u_1
G : ι → Type u_2
H : Type u_3
K : Type u_4
inst✝² : Monoid K
inst✝¹ : (i : ι) → Group (G i)
inst✝ : Group H
φ : (i : ι) → H →* G i
d : Transversal φ
i✝ : ι
g✝ : G i✝
w : NormalWord d
hmw : w.fstIdx ≠ some i✝
hgr : g✝ ∉ (φ i✝).range
n : ↑↑(φ i✝).range × ↑(d.set i✝) := ⋯.equiv (g✝ * (φ i✝) w.head)
w' : Word G := Word.cons (↑n.2) w.toWord hmw ⋯
i : ι
g : G i
h✝ : ⟨i, g⟩ ∈ w.toList
⊢ ⟨i, g⟩ ∈ w.toList

Tactic:
by assumption

Goal state after:
Module: Mathlib.GroupTheory.Perm.Centralizer

Goal state before:
pp: α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g : Perm α
⊢ Nat.card ↥(OnCycleFactors.toPermHom g).ker * ∏ n ∈ g.cycleType.toFinset, (Multiset.count n g.cycleType)! =
    (Fintype.card α - g.cycleType.sum)! * g.cycleType.prod * ∏ n ∈ g.cycleType.toFinset, (Multiset.count n g.cycleType)!

Tactic:
← kerParam_range_card,

Goal state after:
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g : Perm α
⊢ Nat.card ↥(OnCycleFactors.toPermHom g).ker * ∏ n ∈ g.cycleType.toFinset, (Multiset.count n g.cycleType)! =
    Fintype.card ↥(kerParam g).range * ∏ n ∈ g.cycleType.toFinset, (Multiset.count n g.cycleType)!
Module: Mathlib.GroupTheory.SpecificGroups.Alternating.Centralizer

Goal state before:
pp: α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
g : Perm α
h : Subgroup.centralizer {g} ≤ alternatingGroup α
c : Perm α
hc : c ∈ g.cycleFactorsFinset
d : Perm α
hd : d ∈ g.cycleFactorsFinset
hm : #c.support = #d.support
hm' : c ≠ d
τ : Perm ↥g.cycleFactorsFinset := swap ⟨c, hc⟩ ⟨d, hd⟩
a : g.Basis
hτ : τ ∈ range_toPermHom' g
k : ↥(Subgroup.centralizer {g}) := a.toCentralizer ⟨τ, hτ⟩
hk : k = a.toCentralizer ⟨τ, hτ⟩
hk_cT : (↑k).cycleType = Multiset.replicate (↑k).cycleType.card 2
this : (↑k).cycleType.card * 2 = #(↑k).support
that : (↑k).cycleType.card = #c.support
⊢ (↑k).cycleType.card ∈ g.cycleType

Tactic:
rw [that]

Goal state after:
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
g : Perm α
h : Subgroup.centralizer {g} ≤ alternatingGroup α
c : Perm α
hc : c ∈ g.cycleFactorsFinset
d : Perm α
hd : d ∈ g.cycleFactorsFinset
hm : #c.support = #d.support
hm' : c ≠ d
τ : Perm ↥g.cycleFactorsFinset := swap ⟨c, hc⟩ ⟨d, hd⟩
a : g.Basis
hτ : τ ∈ range_toPermHom' g
k : ↥(Subgroup.centralizer {g}) := a.toCentralizer ⟨τ, hτ⟩
hk : k = a.toCentralizer ⟨τ, hτ⟩
hk_cT : (↑k).cycleType = Multiset.replicate (↑k).cycleType.card 2
this : (↑k).cycleType.card * 2 = #(↑k).support
that : (↑k).cycleType.card = #c.support
⊢ #c.support ∈ g.cycleType
Module: Mathlib.GroupTheory.SchurZassenhaus

Goal state before:
pp: G : Type u
inst✝² : Group G
N : Subgroup G
inst✝¹ : N.Normal
h1 : (Nat.card ↥N).Coprime N.index
h2 :
  ∀ (G' : Type u) [inst : Group G'] [Finite G'],
    Nat.card G' < Nat.card G →
      ∀ {N' : Subgroup G'} [N'.Normal], (Nat.card ↥N').Coprime N'.index → ∃ H', N'.IsComplement' H'
h3 : ∀ (H : Subgroup G), ¬N.IsComplement' H
inst✝ : Finite G
this : Fact (Nat.Prime (Nat.card ↥N).minFac)
⊢ IsPGroup (Nat.card ↥N).minFac ↥N

Tactic:
refine Sylow.nonempty.elim fun P => P.2.of_surjective P.1.subtype ?_

Goal state after:
G : Type u
inst✝² : Group G
N : Subgroup G
inst✝¹ : N.Normal
h1 : (Nat.card ↥N).Coprime N.index
h2 :
  ∀ (G' : Type u) [inst : Group G'] [Finite G'],
    Nat.card G' < Nat.card G →
      ∀ {N' : Subgroup G'} [N'.Normal], (Nat.card ↥N').Coprime N'.index → ∃ H', N'.IsComplement' H'
h3 : ∀ (H : Subgroup G), ¬N.IsComplement' H
inst✝ : Finite G
this : Fact (Nat.Prime (Nat.card ↥N).minFac)
P : Sylow (Nat.card ↥N).minFac ↥N
⊢ Function.Surjective ⇑(↑P).subtype
Module: Mathlib.GroupTheory.SchurZassenhaus

Goal state before:
pp: G : Type u
inst✝¹ : Group G
N : Subgroup G
inst✝ : N.Normal
hN : (Nat.card ↥N).Coprime N.index
⊢ ∃ H, N.IsComplement' H

Tactic:
by
  by_cases hN1 : Nat.card N = 0
  · rw [hN1, Nat.coprime_zero_left, index_eq_one] at hN
    rw [hN]
    exact ⟨⊥, isComplement'_top_bot⟩
  by_cases hN2 : N.index = 0
  · rw [hN2, Nat.coprime_zero_right, Nat.card_eq_one_iff_unique] at hN
    have := hN.1
    rw [N.eq_bot_of_subsingleton]
    exact ⟨⊤, isComplement'_bot_top⟩
  have hN3 : Finite G := by
    apply Nat.finite_of_card_ne_zero
    rw [← N.card_mul_index]
    exact mul_ne_zero hN1 hN2
  exact exists_right_complement'_of_coprime_aux' rfl hN

Goal state after:
Module: Mathlib.GroupTheory.SpecificGroups.Alternating.KleinFour

Goal state before:
pp: α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
hα4 : Nat.card α = 4
this : Monoid.exponent ↥(kleinFour α) = 1 ∨ Monoid.exponent ↥(kleinFour α) = 2
⊢ ¬Monoid.exponent ↥(kleinFour α) = 1

Tactic:
Monoid.exp_eq_one_iff,

Goal state after:
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
hα4 : Nat.card α = 4
this : Monoid.exponent ↥(kleinFour α) = 1 ∨ Monoid.exponent ↥(kleinFour α) = 2
⊢ ¬Subsingleton ↥(kleinFour α)
Module: Mathlib.GroupTheory.SpecificGroups.Alternating.Simple

Goal state before:
pp: α : Type u_1
inst✝² : DecidableEq α
inst✝¹ : Fintype α
hα : 5 ≤ Nat.card α
hα' : Nat.card α ≠ 6
N : Subgroup ↥(alternatingGroup α)
inst✝ : N.Normal
⊢ N = ⊥ ∨ N = ⊤

Tactic:
rw [or_iff_not_imp_left, ← ne_eq, ← Subgroup.nontrivial_iff_ne_bot]

Goal state after:
α : Type u_1
inst✝² : DecidableEq α
inst✝¹ : Fintype α
hα : 5 ≤ Nat.card α
hα' : Nat.card α ≠ 6
N : Subgroup ↥(alternatingGroup α)
inst✝ : N.Normal
⊢ Nontrivial ↥N → N = ⊤
Module: Mathlib.GroupTheory.SpecificGroups.Quaternion

Goal state before:
pp: case succ
n k : ℕ
IH : a 1 ^ k = a ↑k
⊢ a ↑k * a 1 = a ↑(k + 1)

Tactic:
a_mul_a

Goal state after:
case succ
n k : ℕ
IH : a 1 ^ k = a ↑k
⊢ a (↑k + 1) = a ↑(k + 1)
Module: Mathlib.GroupTheory.SpecificGroups.Alternating.Simple

Goal state before:
pp: α : Type u_1
inst✝² : DecidableEq α
inst✝¹ : Fintype α
hα : 5 ≤ Nat.card α
hα' : Nat.card α ≠ 8
N : Subgroup ↥(alternatingGroup α)
inst✝ : N.Normal
⊢ N = ⊥ ∨ N = ⊤

Tactic:
rw [or_iff_not_imp_left, ← ne_eq, ← Subgroup.nontrivial_iff_ne_bot]

Goal state after:
α : Type u_1
inst✝² : DecidableEq α
inst✝¹ : Fintype α
hα : 5 ≤ Nat.card α
hα' : Nat.card α ≠ 8
N : Subgroup ↥(alternatingGroup α)
inst✝ : N.Normal
⊢ Nontrivial ↥N → N = ⊤
Module: Mathlib.GroupTheory.PushoutI

Goal state before:
pp: ι : Type u_1
G : ι → Type u_2
H : Type u_3
inst✝¹ : (i : ι) → Group (G i)
inst✝ : Group H
φ : (i : ι) → H →* G i
hφ : ∀ (i : ι), Injective ⇑(φ i)
i j : ι
hij : i ≠ j
⊢ (of i).range ⊓ (of j).range ≤ (base φ).range

Tactic:
intro x ⟨⟨g₁, hg₁⟩, ⟨g₂, hg₂⟩⟩

Goal state after:
ι : Type u_1
G : ι → Type u_2
H : Type u_3
inst✝¹ : (i : ι) → Group (G i)
inst✝ : Group H
φ : (i : ι) → H →* G i
hφ : ∀ (i : ι), Injective ⇑(φ i)
i j : ι
hij : i ≠ j
x : PushoutI φ
g₁ : G i
hg₁ : (of i) g₁ = x
g₂ : G j
hg₂ : (of j) g₂ = x
⊢ x ∈ (base φ).range
Module: Mathlib.GroupTheory.SpecificGroups.ZGroup

Goal state before:
pp: case refine_1
G : Type u_1
inst✝² : Group G
p : ℕ
inst✝¹ : Fact (Nat.Prime p)
P K : Subgroup G
inst✝ : IsCyclic ↥P
hP : IsPGroup p ↥P
hKP : K ≤ Subgroup.normalizer ↑P
hPK : (Nat.card ↥P).Coprime (Nat.card ↥K)
x✝ : MulDistribMulAction ↥K ↥P := MulDistribMulAction.compHom (↥P) (P.normalizerMonoidHom.comp (Subgroup.inclusion hKP))
h : ∀ (g : ↥P) (k : ↥K), k • g * g⁻¹ = 1
⊢ ⁅K, P⁆ = ⊥

pp: case refine_2
G : Type u_1
inst✝² : Group G
p : ℕ
inst✝¹ : Fact (Nat.Prime p)
P K : Subgroup G
inst✝ : IsCyclic ↥P
hP : IsPGroup p ↥P
hKP : K ≤ Subgroup.normalizer ↑P
hPK : (Nat.card ↥P).Coprime (Nat.card ↥K)
x✝ : MulDistribMulAction ↥K ↥P := MulDistribMulAction.compHom (↥P) (P.normalizerMonoidHom.comp (Subgroup.inclusion hKP))
h : ∀ (g : ↥P), ∃ k q, k • q * q⁻¹ = g
⊢ ⁅K, P⁆ = P

Tactic:
· rw [eq_bot_iff, Subgroup.commutator_le]
    exact fun k hk g hg ↦ Subtype.ext_iff.mp (h ⟨g, hg⟩ ⟨k, hk⟩)

Goal state after:
case refine_2
G : Type u_1
inst✝² : Group G
p : ℕ
inst✝¹ : Fact (Nat.Prime p)
P K : Subgroup G
inst✝ : IsCyclic ↥P
hP : IsPGroup p ↥P
hKP : K ≤ Subgroup.normalizer ↑P
hPK : (Nat.card ↥P).Coprime (Nat.card ↥K)
x✝ : MulDistribMulAction ↥K ↥P := MulDistribMulAction.compHom (↥P) (P.normalizerMonoidHom.comp (Subgroup.inclusion hKP))
h : ∀ (g : ↥P), ∃ k q, k • q * q⁻¹ = g
⊢ ⁅K, P⁆ = P
Module: Mathlib.GroupTheory.PushoutI

Goal state before:
pp: ι : Type u_1
G : ι → Type u_2
H : Type u_3
inst✝¹ : (i : ι) → Group (G i)
inst✝ : Group H
φ : (i : ι) → H →* G i
hφ : ∀ (i : ι), Injective ⇑(φ i)
i j : ι
hij : i ≠ j
h : H
⊢ ((of j).comp (φ j)) h ∈ (of j).range

Tactic:
exact MonoidHom.mem_range.2 ⟨φ j h, rfl⟩

Goal state after:
Module: Mathlib.Probability.Kernel.MeasurableLIntegral

Goal state before:
pp: case basic
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ : Kernel α β
t : Set (α × β)
hκs : ∀ (a : α), IsFiniteMeasure (κ a)
t₁ : Set α
ht₁ : MeasurableSet t₁
t₂ : Set β
ht₂ : MeasurableSet t₂
h_eq_ite : (fun a ↦ (κ a) (if a ∈ t₁ then t₂ else ∅)) = fun a ↦ if a ∈ t₁ then (κ a) t₂ else 0
⊢ Measurable fun a ↦ (κ a) (if a ∈ t₁ then t₂ else ∅)

Tactic:
h_eq_ite

Goal state after:
case basic
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ : Kernel α β
t : Set (α × β)
hκs : ∀ (a : α), IsFiniteMeasure (κ a)
t₁ : Set α
ht₁ : MeasurableSet t₁
t₂ : Set β
ht₂ : MeasurableSet t₂
h_eq_ite : (fun a ↦ (κ a) (if a ∈ t₁ then t₂ else ∅)) = fun a ↦ if a ∈ t₁ then (κ a) t₂ else 0
⊢ Measurable fun a ↦ if a ∈ t₁ then (κ a) t₂ else 0
Module: Mathlib.Probability.Kernel.Basic

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ : Kernel α β
μ : Measure α
h : ∀ᵐ (a : α) ∂μ, IsProbabilityMeasure (κ a)
h' : μ ≠ 0
⊢ μ (toMeasurable μ {a | ¬IsProbabilityMeasure (κ a)}) = 0

Tactic:
by simpa [measure_toMeasurable] using! h

Goal state after:
Module: Mathlib.Probability.Kernel.Composition.MeasureCompProd

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
μ : Measure α
inst✝¹ : SFinite μ
κ : Kernel α β
inst✝ : IsMarkovKernel κ
⊢ (μ ⊗ₘ κ).fst = μ

Tactic:
ext s
  rw [compProd, Measure.fst, ← Kernel.fst_apply, Kernel.fst_compProd, Kernel.const_apply]

Goal state after:
Module: Mathlib.Probability.Kernel.Composition.CompMap

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
γ : Type u_4
δ : Type u_5
mγ : MeasurableSpace γ
mδ : MeasurableSpace δ
κ : Kernel α β
η : Kernel γ δ
f : β → γ
hf : Measurable f
⊢ η ∘ₖ κ.map f = η.comap f hf ∘ₖ κ

Tactic:
ext x s ms
  rw [comp_apply' _ _ _ ms, lintegral_map _ hf _ (η.measurable_coe ms), comp_apply' _ _ _ ms]
  simp_rw [comap_apply']

Goal state after:
Module: Mathlib.Probability.Kernel.Composition.MeasureCompProd

Goal state before:
pp: case pos
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
μ ν : Measure α
hμν : μ ⟂ₘ ν
κ η : Kernel α β
hμ : SFinite μ
hν : SFinite ν
hκ : IsSFiniteKernel κ
hη : IsSFiniteKernel η
⊢ μ ⊗ₘ κ ⟂ₘ ν ⊗ₘ η

Tactic:
refine ⟨hμν.nullSet ×ˢ univ, hμν.measurableSet_nullSet.prod .univ, ?_⟩

Goal state after:
case pos
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
μ ν : Measure α
hμν : μ ⟂ₘ ν
κ η : Kernel α β
hμ : SFinite μ
hν : SFinite ν
hκ : IsSFiniteKernel κ
hη : IsSFiniteKernel η
⊢ (μ ⊗ₘ κ) (hμν.nullSet ×ˢ univ) = 0 ∧ (ν ⊗ₘ η) (hμν.nullSet ×ˢ univ)ᶜ = 0
Module: Mathlib.Probability.Kernel.Composition.MeasureComp

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
μ : Measure α
inst✝¹ : SFinite μ
κ : Kernel α β
inst✝ : IsSFiniteKernel κ
s : Set β
hs : MeasurableSet s
⊢ (μ ⊗ₘ κ).snd s = (⇑κ ∘ₘ μ) s

Tactic:
rw [bind_apply hs κ.aemeasurable, snd_apply hs, compProd_apply]

Goal state after:
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
μ : Measure α
inst✝¹ : SFinite μ
κ : Kernel α β
inst✝ : IsSFiniteKernel κ
s : Set β
hs : MeasurableSet s
⊢ ∫⁻ (a : α), (κ a) (Prod.mk a ⁻¹' Prod.snd ⁻¹' s) ∂μ = ∫⁻ (a : α), (κ a) s ∂μ

α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
μ : Measure α
inst✝¹ : SFinite μ
κ : Kernel α β
inst✝ : IsSFiniteKernel κ
s : Set β
hs : MeasurableSet s
⊢ MeasurableSet (Prod.snd ⁻¹' s)
Module: Mathlib.Probability.Kernel.Composition.Prod

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
γ : Type u_4
mγ : MeasurableSpace γ
δ : Type u_6
mδ : MeasurableSpace δ
κ : Kernel α β
inst✝² : IsSFiniteKernel κ
η : Kernel β γ
inst✝¹ : IsSFiniteKernel η
μ : Measure δ
inst✝ : SFinite μ
x : α
s : Set (γ × δ)
ms : MeasurableSet s
⊢ ∫⁻ (b : β), ∫⁻ (b : γ), μ (Prod.mk b ⁻¹' s) ∂η b ∂κ x = ∫⁻ (b : γ), μ (Prod.mk b ⁻¹' s) ∂(η ∘ₖ κ) x

Tactic:
lintegral_comp _ _ _ (measurable_measure_prodMk_left ms)

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Decomposition.IntegralRNDeriv

Goal state before:
pp: 𝓧 : Type u_1
m𝓧 : MeasurableSpace 𝓧
μ ν : Measure 𝓧
𝓨 : Type u_2
m𝓨 : MeasurableSpace 𝓨
κ η : Kernel 𝓧 𝓨
f : ℝ → ℝ
inst✝³ : IsFiniteMeasure μ
inst✝² : IsFiniteMeasure ν
inst✝¹ : IsMarkovKernel κ
inst✝ : IsMarkovKernel η
hf : StronglyMeasurable f
hf_cvx : ConvexOn ℝ (Ici 0) f
hf_cont_at : ContinuousWithinAt f (Ici 0) 0
h_int :
  (∀ᵐ (x : 𝓧) ∂ν, Integrable (fun y ↦ f ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (x, y)).toReal) (η x)) ∧
    Integrable (fun x ↦ ∫ (y : 𝓨), ‖f ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (x, y)).toReal‖ ∂η x) ν
hκη : μ ⊗ₘ κ ≪ μ ⊗ₘ η
hf_cont : ContinuousOn f (Ici 0)
h_lt_top : ∀ᵐ (a : 𝓧) ∂ν, ∀ᵐ (b : 𝓨) ∂η a, (μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (a, b) < ∞
h_integrable :
  (∀ᵐ (x : 𝓧) ∂ν, Integrable (fun y ↦ ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (x, y)).toReal) (η x)) ∧
    Integrable (fun x ↦ ∫ (y : 𝓨), ‖((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (x, y)).toReal‖ ∂η x) ν
h_ae1 : ∀ᵐ (a : 𝓧) ∂ν, μ.rnDeriv ν a * ∫⁻ (b : 𝓨), (μ ⊗ₘ κ).rnDeriv (μ ⊗ₘ η) (a, b) ∂η a = μ.rnDeriv ν a
⊢ (fun a ↦ f (μ.rnDeriv ν a).toReal) ≤ᵐ[ν] fun a ↦ ∫ (b : 𝓨), f ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (a, b)).toReal ∂η a

Tactic:
have h_ae2 : ∀ᵐ a ∂ν, ∀ᵐ b ∂(η a), μ.rnDeriv ν a * (μ ⊗ₘ κ).rnDeriv (μ ⊗ₘ η) (a, b) =
      (μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (a, b) := by
    have h_compProd : (fun p ↦ μ.rnDeriv ν p.1 * (μ ⊗ₘ κ).rnDeriv (μ ⊗ₘ η) p) =ᵐ[ν ⊗ₘ η]
        (μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) := (rnDeriv_compProd hκη ν).symm
    rwa [Filter.EventuallyEq, Measure.ae_compProd_iff] at h_compProd
    simp only [measurableSet_setOfPred]
    fun_prop

Goal state after:
𝓧 : Type u_1
m𝓧 : MeasurableSpace 𝓧
μ ν : Measure 𝓧
𝓨 : Type u_2
m𝓨 : MeasurableSpace 𝓨
κ η : Kernel 𝓧 𝓨
f : ℝ → ℝ
inst✝³ : IsFiniteMeasure μ
inst✝² : IsFiniteMeasure ν
inst✝¹ : IsMarkovKernel κ
inst✝ : IsMarkovKernel η
hf : StronglyMeasurable f
hf_cvx : ConvexOn ℝ (Ici 0) f
hf_cont_at : ContinuousWithinAt f (Ici 0) 0
h_int :
  (∀ᵐ (x : 𝓧) ∂ν, Integrable (fun y ↦ f ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (x, y)).toReal) (η x)) ∧
    Integrable (fun x ↦ ∫ (y : 𝓨), ‖f ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (x, y)).toReal‖ ∂η x) ν
hκη : μ ⊗ₘ κ ≪ μ ⊗ₘ η
hf_cont : ContinuousOn f (Ici 0)
h_lt_top : ∀ᵐ (a : 𝓧) ∂ν, ∀ᵐ (b : 𝓨) ∂η a, (μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (a, b) < ∞
h_integrable :
  (∀ᵐ (x : 𝓧) ∂ν, Integrable (fun y ↦ ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (x, y)).toReal) (η x)) ∧
    Integrable (fun x ↦ ∫ (y : 𝓨), ‖((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (x, y)).toReal‖ ∂η x) ν
h_ae1 : ∀ᵐ (a : 𝓧) ∂ν, μ.rnDeriv ν a * ∫⁻ (b : 𝓨), (μ ⊗ₘ κ).rnDeriv (μ ⊗ₘ η) (a, b) ∂η a = μ.rnDeriv ν a
h_ae2 :
  ∀ᵐ (a : 𝓧) ∂ν, ∀ᵐ (b : 𝓨) ∂η a, μ.rnDeriv ν a * (μ ⊗ₘ κ).rnDeriv (μ ⊗ₘ η) (a, b) = (μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (a, b)
⊢ (fun a ↦ f (μ.rnDeriv ν a).toReal) ≤ᵐ[ν] fun a ↦ ∫ (b : 𝓨), f ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) (a, b)).toReal ∂η a
Module: Mathlib.MeasureTheory.Measure.Decomposition.IntegralRNDeriv

Goal state before:
pp: 𝓧 : Type u_1
m𝓧 : MeasurableSpace 𝓧
μ ν : Measure 𝓧
𝓨 : Type u_2
m𝓨 : MeasurableSpace 𝓨
κ η : Kernel 𝓧 𝓨
f : ℝ → ℝ
inst✝³ : IsFiniteMeasure μ
inst✝² : IsFiniteMeasure ν
inst✝¹ : IsMarkovKernel κ
inst✝ : IsMarkovKernel η
hf : StronglyMeasurable f
hf_cvx : ConvexOn ℝ (Ici 0) f
hf_cont_at : ContinuousWithinAt f (Ici 0) 0
hf_int : Integrable (fun p ↦ f ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) p).toReal) (ν ⊗ₘ η)
hκη : μ ⊗ₘ κ ≪ μ ⊗ₘ η
hf_cont : ContinuousOn f (Ici 0)
⊢ Integrable (fun a ↦ f (μ.rnDeriv ν a).toReal) ν

Tactic:
obtain ⟨c, c', h⟩ : ∃ c c', ∀ x, 0 ≤ x → c * x + c' ≤ f x :=
    hf_cvx.exists_affine_le_real isClosed_Ici hf_cont.lowerSemicontinuousOn

Goal state after:
𝓧 : Type u_1
m𝓧 : MeasurableSpace 𝓧
μ ν : Measure 𝓧
𝓨 : Type u_2
m𝓨 : MeasurableSpace 𝓨
κ η : Kernel 𝓧 𝓨
f : ℝ → ℝ
inst✝³ : IsFiniteMeasure μ
inst✝² : IsFiniteMeasure ν
inst✝¹ : IsMarkovKernel κ
inst✝ : IsMarkovKernel η
hf : StronglyMeasurable f
hf_cvx : ConvexOn ℝ (Ici 0) f
hf_cont_at : ContinuousWithinAt f (Ici 0) 0
hf_int : Integrable (fun p ↦ f ((μ ⊗ₘ κ).rnDeriv (ν ⊗ₘ η) p).toReal) (ν ⊗ₘ η)
hκη : μ ⊗ₘ κ ≪ μ ⊗ₘ η
hf_cont : ContinuousOn f (Ici 0)
c c' : ℝ
h : ∀ (x : ℝ), 0 ≤ x → c * x + c' ≤ f x
⊢ Integrable (fun a ↦ f (μ.rnDeriv ν a).toReal) ν
Module: Mathlib.MeasureTheory.Function.LpSpace.CompleteOfCompleteLp

Goal state before:
pp: α : Type u_1
E : Type u_2
inst✝³ : NormedAddCommGroup E
mα : MeasurableSpace α
p : ℝ≥0∞
μ : Measure α
inst✝² : NormedSpace ℝ E
hp : Fact (1 ≤ p)
inst✝¹ : CompleteSpace ↥(Lp E p μ)
inst✝ : Nontrivial ↥(Lp E p μ)
⊢ ∃ f, f ≠ 0

Tactic:
have : Nontrivial (Lp ℝ p μ) := nontrivial_Lp_real_of_nontrivial_Lp E p μ
    exact exists_ne 0

Goal state after:
Module: Mathlib.MeasureTheory.Function.ConditionalExpectation.CondexpL2

Goal state before:
pp: α : Type u_1
E : Type u_2
𝕜 : Type u_7
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
inst✝ : CompleteSpace E
m m0 : MeasurableSpace α
μ : Measure α
s : Set α
hm : m ≤ m0
hs : MeasurableSet s
hμs : μ s ≠ ∞
c : E
⊢ ↑((condExpL2 E 𝕜 hm) (indicatorConstLp 2 ⋯ hμs c)) = indicatorConstLp 2 ⋯ hμs c

Tactic:
rw [condExpL2]
  have : Fact (m ≤ m0) := ⟨hm⟩
  have h_mem : indicatorConstLp 2 (hm s hs) hμs c ∈ lpMeas E 𝕜 m 2 μ :=
    mem_lpMeas_indicatorConstLp hm hs hμs
  let ind := (⟨indicatorConstLp 2 (hm s hs) hμs c, h_mem⟩ : lpMeas E 𝕜 m 2 μ)
  have h_coe_ind : (ind : α →₂[μ] E) = indicatorConstLp 2 (hm s hs) hμs c := rfl
  have h_orth_mem := Submodule.orthogonalProjectionOnto_mem_subspace_eq_self ind
  rw [← h_coe_ind, h_orth_mem]

Goal state after:
Module: Mathlib.MeasureTheory.Function.ConditionalExpectation.CondexpL1

Goal state before:
pp: case neg
α : Type u_1
G : Type u_4
inst✝² : NormedAddCommGroup G
m m0 : MeasurableSpace α
μ : Measure α
s : Set α
inst✝¹ : NormedSpace ℝ G
hm : m ≤ m0
inst✝ : SigmaFinite (μ.trim hm)
c : ℝ
x : G
hs : ¬MeasurableSet s
⊢ condExpIndL1 hm μ s (c • x) = c • condExpIndL1 hm μ s x

Tactic:
simp_rw [condExpIndL1_of_not_measurableSet hs]; rw [smul_zero]

Goal state after:
Module: Mathlib.MeasureTheory.Function.ConditionalExpectation.CondexpL1

Goal state before:
pp: case neg
α : Type u_1
F : Type u_2
𝕜 : Type u_6
inst✝⁵ : RCLike 𝕜
inst✝⁴ : NormedAddCommGroup F
inst✝³ : NormedSpace 𝕜 F
m m0 : MeasurableSpace α
μ : Measure α
s : Set α
hm : m ≤ m0
inst✝² : SigmaFinite (μ.trim hm)
inst✝¹ : NormedSpace ℝ F
inst✝ : SMulCommClass ℝ 𝕜 F
c : 𝕜
x : F
hs : ¬MeasurableSet s
⊢ condExpIndL1 hm μ s (c • x) = c • condExpIndL1 hm μ s x

Tactic:
simp_rw [condExpIndL1_of_not_measurableSet hs]; rw [smul_zero]

Goal state after:
Module: Mathlib.MeasureTheory.Function.LpSpace.InfiniteSum

Goal state before:
pp: case inr
X : Type u_1
E : Type u_2
x✝ : MeasurableSpace X
μ : Measure X
inst✝¹ : NormedAddCommGroup E
ι : Type u_3
inst✝ : Countable ι
p : ℝ≥0∞
hp : 1 ≤ p
f : ι → X → E
hf : ∀ (n : ι), AEStronglyMeasurable (f n) μ
h'f : ∑' (n : ι), eLpNorm (f n) p μ ≠ ∞
h'p : p < ∞
A : ∀ (s : Set X), MeasurableSet s → μ s ≠ ∞ → ∀ᵐ (x : X) ∂μ, x ∈ s → ∑' (n : ι), ‖f n x‖ₑ < ∞
s : ι → Set X
s_meas : ∀ (n : ι), MeasurableSet (s n)
hs : ∀ (n : ι), f n =ᵐ[μ.restrict (s n)ᶜ] 0
h's : ∀ (n : ι), SigmaFinite (μ.restrict (s n))
⊢ ∀ᵐ (a : X) ∂μ, ∑' (n : ι), ‖f n a‖ₑ < ∞

Tactic:
have C : ∀ᵐ x ∂μ, ∀ n, x ∈ s n → ∑' n, ‖f n x‖ₑ < ∞ := by
    apply ae_all_iff.2 (fun n ↦ ?_)
    have : ∀ᵐ x ∂μ, ∀ i, x ∈ s n ∩ spanningSets (μ.restrict (s n)) i → ∑' n, ‖f n x‖ₑ < ∞ := by
      apply ae_all_iff.2 (fun i ↦ ?_)
      apply A _ ((s_meas n).inter (measurableSet_spanningSets _ _))
      rw [Set.inter_comm, ← Measure.restrict_apply' (s_meas n)]
      exact (measure_spanningSets_lt_top _ _).ne
    filter_upwards [this] with x hx h'x
    obtain ⟨i, hi⟩ : ∃ i, x ∈ spanningSets (μ.restrict (s n)) i := ⟨_, mem_spanningSetsIndex _ _⟩
    exact hx i ⟨h'x, hi⟩

Goal state after:
case inr
X : Type u_1
E : Type u_2
x✝ : MeasurableSpace X
μ : Measure X
inst✝¹ : NormedAddCommGroup E
ι : Type u_3
inst✝ : Countable ι
p : ℝ≥0∞
hp : 1 ≤ p
f : ι → X → E
hf : ∀ (n : ι), AEStronglyMeasurable (f n) μ
h'f : ∑' (n : ι), eLpNorm (f n) p μ ≠ ∞
h'p : p < ∞
A : ∀ (s : Set X), MeasurableSet s → μ s ≠ ∞ → ∀ᵐ (x : X) ∂μ, x ∈ s → ∑' (n : ι), ‖f n x‖ₑ < ∞
s : ι → Set X
s_meas : ∀ (n : ι), MeasurableSet (s n)
hs : ∀ (n : ι), f n =ᵐ[μ.restrict (s n)ᶜ] 0
h's : ∀ (n : ι), SigmaFinite (μ.restrict (s n))
C : ∀ᵐ (x : X) ∂μ, ∀ (n : ι), x ∈ s n → ∑' (n : ι), ‖f n x‖ₑ < ∞
⊢ ∀ᵐ (a : X) ∂μ, ∑' (n : ι), ‖f n a‖ₑ < ∞