mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.MeasureTheory.Measure.Trim

Goal state before:
pp: α : Type u_1
m m0 : MeasurableSpace α
μ : Measure α
s : Set α
hm : m ≤ m0
h : (μ.trim hm) s = 0
⊢ μ s = 0

Tactic:
by
  grw [← nonpos_iff_eq_zero, ← h, le_trim hm]

Goal state after:
Module: Mathlib.Data.Set.MemPartition

Goal state before:
pp: case succ.inr.inr
α : Type u_1
f : ℕ → Set α
n : ℕ
ih : ∀ {u v : Set α}, u ∈ memPartition f n → v ∈ memPartition f n → u ≠ v → Disjoint u v
u' : Set α
hu' : u' ∈ memPartition f n
v' : Set α
hv' : v' ∈ memPartition f n
huv : u' \ f n ≠ v' \ f n
⊢ Disjoint (u' \ f n) (v' \ f n)

Tactic:
refine Disjoint.mono sdiff_subset sdiff_subset (ih hu' hv' ?_)

Goal state after:
case succ.inr.inr
α : Type u_1
f : ℕ → Set α
n : ℕ
ih : ∀ {u v : Set α}, u ∈ memPartition f n → v ∈ memPartition f n → u ≠ v → Disjoint u v
u' : Set α
hu' : u' ∈ memPartition f n
v' : Set α
hv' : v' ∈ memPartition f n
huv : u' \ f n ≠ v' \ f n
⊢ u' ≠ v'
Module: Mathlib.MeasureTheory.Measure.Restrict

Goal state before:
pp: α : Type u_2
δ : Type u_4
m0 : MeasurableSpace α
μ : Measure α
f g : α → δ
s : Set α
hfg : f =ᵐ[μ] g
⊢ f =ᵐ[μ.restrict s] g

Tactic:
refine hfg.filter_mono ?_

Goal state after:
α : Type u_2
δ : Type u_4
m0 : MeasurableSpace α
μ : Measure α
f g : α → δ
s : Set α
hfg : f =ᵐ[μ] g
⊢ ae (μ.restrict s) ≤ ae μ
Module: Mathlib.Order.Filter.CountableSeparatingOn

Goal state before:
pp: case refine_2
α : Type u_1
l : Filter α
inst✝ : CountableInterFilter l
p : Set α → Prop
s : Set α
h : HasCountableSeparatingOn α p s
hs : s ∈ l
hl : ∀ (U : Set α), p U → U ∈ l ∨ Uᶜ ∈ l
S : Set (Set α)
hSc : S.Countable
hSp : ∀ s ∈ S, p s
hS : ∀ x ∈ s, ∀ y ∈ s, (∀ s ∈ S, x ∈ s ↔ y ∈ s) → x = y
x : α
⊢ x ∈ s ∩ ⋂₀ (S ∩ l.sets) ∩ ⋂ U ∈ S, ⋂ (_ : Uᶜ ∈ l), Uᶜ →
    ∀ ⦃y : α⦄, y ∈ s ∩ ⋂₀ (S ∩ l.sets) ∩ ⋂ U ∈ S, ⋂ (_ : Uᶜ ∈ l), Uᶜ → x = y

Tactic:
hx

Goal state after:
case refine_2
α : Type u_1
l : Filter α
inst✝ : CountableInterFilter l
p : Set α → Prop
s : Set α
h : HasCountableSeparatingOn α p s
hs : s ∈ l
hl : ∀ (U : Set α), p U → U ∈ l ∨ Uᶜ ∈ l
S : Set (Set α)
hSc : S.Countable
hSp : ∀ s ∈ S, p s
hS : ∀ x ∈ s, ∀ y ∈ s, (∀ s ∈ S, x ∈ s ↔ y ∈ s) → x = y
x : α
hx : x ∈ s ∩ ⋂₀ (S ∩ l.sets) ∩ ⋂ U ∈ S, ⋂ (_ : Uᶜ ∈ l), Uᶜ
⊢ ∀ ⦃y : α⦄, y ∈ s ∩ ⋂₀ (S ∩ l.sets) ∩ ⋂ U ∈ S, ⋂ (_ : Uᶜ ∈ l), Uᶜ → x = y
Module: Mathlib.Order.Filter.CountableSeparatingOn

Goal state before:
pp: α : Type u_1
β : Type u_2
l : Filter α
inst✝ : CountableInterFilter l
f g : α → β
p : Set β → Prop
s : Set β
h' : HasCountableSeparatingOn β p s
hf : ∀ᶠ (x : α) in l, f x ∈ s
hg : ∀ᶠ (x : α) in l, g x ∈ s
h : ∀ (U : Set β), p U → ∀ᶠ (x : α) in l, f x ∈ U ↔ g x ∈ U
S : Set (Set β)
hSc : S.Countable
hSp : ∀ s ∈ S, p s
hS : ∀ x ∈ s, ∀ y ∈ s, (∀ s ∈ S, x ∈ s ↔ y ∈ s) → x = y
H : ∀ᶠ (x : α) in l, ∀ s ∈ S, f x ∈ s ↔ g x ∈ s
x : α
⊢ (∀ s ∈ S, f x ∈ s ↔ g x ∈ s) → f x ∈ s → g x ∈ s → f x = g x

Tactic:
hx

Goal state after:
α : Type u_1
β : Type u_2
l : Filter α
inst✝ : CountableInterFilter l
f g : α → β
p : Set β → Prop
s : Set β
h' : HasCountableSeparatingOn β p s
hf : ∀ᶠ (x : α) in l, f x ∈ s
hg : ∀ᶠ (x : α) in l, g x ∈ s
h : ∀ (U : Set β), p U → ∀ᶠ (x : α) in l, f x ∈ U ↔ g x ∈ U
S : Set (Set β)
hSc : S.Countable
hSp : ∀ s ∈ S, p s
hS : ∀ x ∈ s, ∀ y ∈ s, (∀ s ∈ S, x ∈ s ↔ y ∈ s) → x = y
H : ∀ᶠ (x : α) in l, ∀ s ∈ S, f x ∈ s ↔ g x ∈ s
x : α
hx : ∀ s ∈ S, f x ∈ s ↔ g x ∈ s
⊢ f x ∈ s → g x ∈ s → f x = g x
Module: Mathlib.MeasureTheory.Measure.Restrict

Goal state before:
pp: α : Type u_2
m0 : MeasurableSpace α
μ : Measure α
s t : Set α
ht : t ⊆ s
h : NullMeasurableSet t (μ.restrict s)
t' : Set α
t'_subs : t' ⊆ t
ht' : MeasurableSet t'
t't : t' =ᵐ[μ.restrict s] t
x : α
⊢ t' x = t x → (x ∈ t' ↔ x ∈ t)

Tactic:
hx

Goal state after:
α : Type u_2
m0 : MeasurableSpace α
μ : Measure α
s t : Set α
ht : t ⊆ s
h : NullMeasurableSet t (μ.restrict s)
t' : Set α
t'_subs : t' ⊆ t
ht' : MeasurableSet t'
t't : t' =ᵐ[μ.restrict s] t
x : α
hx : t' x = t x
⊢ x ∈ t' ↔ x ∈ t
Module: Mathlib.MeasureTheory.Measure.Restrict

Goal state before:
pp: α : Type u_2
m0 : MeasurableSpace α
μ : Measure α
s t : Set α
ht : t ⊆ s
h : NullMeasurableSet t (μ.restrict s)
t' : Set α
t'_subs : t' ⊆ t
ht' : MeasurableSet t'
t't : t' =ᵐ[μ.restrict s] t
this : ∀ᵐ (x : α) ∂μ, x ∈ s → (x ∈ t' ↔ x ∈ t)
x : α
⊢ (x ∈ s → (x ∈ t' ↔ x ∈ t)) → t' x = t x

Tactic:
hx

Goal state after:
α : Type u_2
m0 : MeasurableSpace α
μ : Measure α
s t : Set α
ht : t ⊆ s
h : NullMeasurableSet t (μ.restrict s)
t' : Set α
t'_subs : t' ⊆ t
ht' : MeasurableSet t'
t't : t' =ᵐ[μ.restrict s] t
this : ∀ᵐ (x : α) ∂μ, x ∈ s → (x ∈ t' ↔ x ∈ t)
x : α
hx : x ∈ s → (x ∈ t' ↔ x ∈ t)
⊢ t' x = t x
Module: Mathlib.MeasureTheory.MeasurableSpace.CountablyGenerated

Goal state before:
pp: case h₁
α : Type u_1
β : Type u_2
inst✝¹ : MeasurableSpace α
inst✝ : Countable α
s : Set α
hs : MeasurableSet s
x : α
⊢ x ∈ s → x ∈ ⋃ y ∈ s, measurableAtom y

Tactic:
hx

Goal state after:
case h₁
α : Type u_1
β : Type u_2
inst✝¹ : MeasurableSpace α
inst✝ : Countable α
s : Set α
hs : MeasurableSet s
x : α
hx : x ∈ s
⊢ x ∈ ⋃ y ∈ s, measurableAtom y
Module: Mathlib.MeasureTheory.MeasurableSpace.CountablyGenerated

Goal state before:
pp: case h₂
α : Type u_1
β : Type u_2
inst✝¹ : MeasurableSpace α
inst✝ : Countable α
s : Set α
hs : MeasurableSet s
x : α
⊢ x ∈ s → measurableAtom x ⊆ s

Tactic:
hx

Goal state after:
case h₂
α : Type u_1
β : Type u_2
inst✝¹ : MeasurableSpace α
inst✝ : Countable α
s : Set α
hs : MeasurableSet s
x : α
hx : x ∈ s
⊢ measurableAtom x ⊆ s
Module: Mathlib.MeasureTheory.Measure.Typeclasses.SFinite

Goal state before:
pp: α : Type u_1
μ : Measure α
h this : SigmaFinite μ
s : ℕ → Set α := spanningSets μ
hs_meas : ∀ (i : ℕ), s i = ∅ ∨ s i = univ
h_univ_empty : ¬univ = ∅
h_not_univ : ∀ (i : ℕ), s i ≠ univ
h_empty : ∀ (i : ℕ), s i = ∅
hs_univ : ∅ = univ
⊢ False

Tactic:
exact h_univ_empty hs_univ.symm

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

Goal state before:
pp: α : Type u_2
β : Type u_3
inst✝¹ : MeasurableSpace α
μ : Measure α
s : Set α
f : α → β
inst✝ : Zero β
hs : MeasurableSet s
hf : ∀ᵐ (x : α) ∂μ, x ∈ sᶜ → f x = 0 x
x : α
⊢ (x ∈ sᶜ → f x = 0 x) → s.indicator f x = f x

Tactic:
hx

Goal state after:
α : Type u_2
β : Type u_3
inst✝¹ : MeasurableSpace α
μ : Measure α
s : Set α
f : α → β
inst✝ : Zero β
hs : MeasurableSet s
hf : ∀ᵐ (x : α) ∂μ, x ∈ sᶜ → f x = 0 x
x : α
hx : x ∈ sᶜ → f x = 0 x
⊢ s.indicator f x = f x
Module: Mathlib.MeasureTheory.Measure.Restrict

Goal state before:
pp: α : Type u_2
β : Type u_3
inst✝¹ : MeasurableSpace α
μ : Measure α
s : Set α
f : α → β
inst✝ : Zero β
hs : MeasurableSet s
hf : ∀ᵐ (x : α) ∂μ, x ∈ s → f x = 0 x
x : α
⊢ (x ∈ s → f x = 0 x) → s.indicator f x = 0 x

Tactic:
hx

Goal state after:
α : Type u_2
β : Type u_3
inst✝¹ : MeasurableSpace α
μ : Measure α
s : Set α
f : α → β
inst✝ : Zero β
hs : MeasurableSet s
hf : ∀ᵐ (x : α) ∂μ, x ∈ s → f x = 0 x
x : α
hx : x ∈ s → f x = 0 x
⊢ s.indicator f x = 0 x
Module: Mathlib.MeasureTheory.Measure.Restrict

Goal state before:
pp: α : Type u_2
β : Type u_3
inst✝¹ : MeasurableSpace α
μ : Measure α
s : Set α
f : α → β
inst✝ : Zero β
g : α → β
hs : MeasurableSet s
h : ∀ᵐ (x : α) ∂μ, x ∈ s → f x = g x
x : α
⊢ (x ∈ s → f x = g x) → s.indicator f x = s.indicator g x

Tactic:
hx

Goal state after:
α : Type u_2
β : Type u_3
inst✝¹ : MeasurableSpace α
μ : Measure α
s : Set α
f : α → β
inst✝ : Zero β
g : α → β
hs : MeasurableSet s
h : ∀ᵐ (x : α) ∂μ, x ∈ s → f x = g x
x : α
hx : x ∈ s → f x = g x
⊢ s.indicator f x = s.indicator g x
Module: Mathlib.MeasureTheory.Measure.Restrict

Goal state before:
pp: α : Type u_2
β : Type u_3
inst✝¹ : MeasurableSpace α
μ : Measure α
s : Set α
f : α → β
inst✝ : Zero β
g : α → β
hs : MeasurableSet s
h : s.indicator f =ᵐ[μ] s.indicator g
x : α
⊢ s.indicator f x = s.indicator g x → x ∈ s → f x = g x

Tactic:
hx

Goal state after:
α : Type u_2
β : Type u_3
inst✝¹ : MeasurableSpace α
μ : Measure α
s : Set α
f : α → β
inst✝ : Zero β
g : α → β
hs : MeasurableSet s
h : s.indicator f =ᵐ[μ] s.indicator g
x : α
hx : s.indicator f x = s.indicator g x
⊢ x ∈ s → f x = g x
Module: Mathlib.MeasureTheory.Measure.Restrict

Goal state before:
pp: α : Type u_2
ι : Type u_6
x✝ : MeasurableSpace α
μ : Measure α
s : ι → Set α
M : ℕ
hs_meas : ∀ (i : ι), MeasurableSet (s i)
hs : ∀ (y : α), {i | y ∈ s i}.encard ≤ ↑M
t : Set α
ht : MeasurableSet t
F : Finset ι
P : Finset ι → Set α := fun C ↦ (⋂ i ∈ C, s i) ∩ ⋂ i ∈ F \ C, (s i)ᶜ
Cs : Finset (Finset ι) := F.powerset \ {∅}
G : ι → Set (Finset ι) := fun i ↦ {C | C ∈ F.powerset ∧ i ∈ C}
P_meas : ∀ (C : Finset ι), MeasurableSet (P C)
P_cover : ∀ {i : ι}, i ∈ F → s i ⊆ ⋃ C ∈ G i, P C
x : α
⊢ x ∈ ⋃ C ∈ Cs, P C → x ∈ ⋃ i, s i

Tactic:
hx

Goal state after:
α : Type u_2
ι : Type u_6
x✝ : MeasurableSpace α
μ : Measure α
s : ι → Set α
M : ℕ
hs_meas : ∀ (i : ι), MeasurableSet (s i)
hs : ∀ (y : α), {i | y ∈ s i}.encard ≤ ↑M
t : Set α
ht : MeasurableSet t
F : Finset ι
P : Finset ι → Set α := fun C ↦ (⋂ i ∈ C, s i) ∩ ⋂ i ∈ F \ C, (s i)ᶜ
Cs : Finset (Finset ι) := F.powerset \ {∅}
G : ι → Set (Finset ι) := fun i ↦ {C | C ∈ F.powerset ∧ i ∈ C}
P_meas : ∀ (C : Finset ι), MeasurableSet (P C)
P_cover : ∀ {i : ι}, i ∈ F → s i ⊆ ⋃ C ∈ G i, P C
x : α
hx : x ∈ ⋃ C ∈ Cs, P C
⊢ x ∈ ⋃ i, s i
Module: Mathlib.MeasureTheory.Measure.Typeclasses.SFinite

Goal state before:
pp: α : Type u_1
m0 : MeasurableSpace α
μ ν : Measure α
inst✝¹ : SigmaFinite μ
inst✝ : SigmaFinite ν
P : α → Prop
h : ∀ (s : Set α), MeasurableSet s → μ s < ∞ → ν s < ∞ → ∀ᵐ (x : α) ∂μ.restrict s, P x
this : ∀ (n : ℕ), ∀ᵐ (x : α) ∂μ, x ∈ spanningSets (μ + ν) n → P x
a✝ : α
⊢ (∀ (i : ℕ), a✝ ∈ spanningSets (μ + ν) i → P a✝) → P a✝

Tactic:
hx

Goal state after:
α : Type u_1
m0 : MeasurableSpace α
μ ν : Measure α
inst✝¹ : SigmaFinite μ
inst✝ : SigmaFinite ν
P : α → Prop
h : ∀ (s : Set α), MeasurableSet s → μ s < ∞ → ν s < ∞ → ∀ᵐ (x : α) ∂μ.restrict s, P x
this : ∀ (n : ℕ), ∀ᵐ (x : α) ∂μ, x ∈ spanningSets (μ + ν) n → P x
a✝ : α
hx : ∀ (i : ℕ), a✝ ∈ spanningSets (μ + ν) i → P a✝
⊢ P a✝
Module: Mathlib.MeasureTheory.Measure.Restrict

Goal state before:
pp: α : Type u_2
ι : Type u_6
x✝ : MeasurableSpace α
μ : Measure α
s : ι → Set α
M : ℕ
hs_meas : ∀ (i : ι), MeasurableSet (s i)
hs : ∀ (y : α), {i | y ∈ s i}.encard ≤ ↑M
t : Set α
ht : MeasurableSet t
F : Finset ι
P : Finset ι → Set α := fun C ↦ (⋂ i ∈ C, s i) ∩ ⋂ i ∈ F \ C, (s i)ᶜ
Cs : Finset (Finset ι) := F.powerset \ {∅}
G : ι → Set (Finset ι) := fun i ↦ {C | C ∈ F.powerset ∧ i ∈ C}
P_meas : ∀ (C : Finset ι), MeasurableSet (P C)
P_cover : ∀ {i : ι}, i ∈ F → s i ⊆ ⋃ C ∈ G i, P C
iUnion_P : ⋃ C ∈ Cs, P C ⊆ ⋃ i, s i
i : ι
C : Finset ι
hiC : i ∈ C
x : α
⊢ x ∈ P C → x ∈ s i

Tactic:
hx

Goal state after:
α : Type u_2
ι : Type u_6
x✝ : MeasurableSpace α
μ : Measure α
s : ι → Set α
M : ℕ
hs_meas : ∀ (i : ι), MeasurableSet (s i)
hs : ∀ (y : α), {i | y ∈ s i}.encard ≤ ↑M
t : Set α
ht : MeasurableSet t
F : Finset ι
P : Finset ι → Set α := fun C ↦ (⋂ i ∈ C, s i) ∩ ⋂ i ∈ F \ C, (s i)ᶜ
Cs : Finset (Finset ι) := F.powerset \ {∅}
G : ι → Set (Finset ι) := fun i ↦ {C | C ∈ F.powerset ∧ i ∈ C}
P_meas : ∀ (C : Finset ι), MeasurableSet (P C)
P_cover : ∀ {i : ι}, i ∈ F → s i ⊆ ⋃ C ∈ G i, P C
iUnion_P : ⋃ C ∈ Cs, P C ⊆ ⋃ i, s i
i : ι
C : Finset ι
hiC : i ∈ C
x : α
hx : x ∈ P C
⊢ x ∈ s i
Module: Mathlib.MeasureTheory.Measure.AEMeasurable

Goal state before:
pp: ι : Type u_1
α : Type u_2
β : Type u_3
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
f : α → β
inst✝ : Countable ι
μ : ι → Measure α
h : ∀ (i : ι), AEMeasurable f (μ i)
a✝ : Nontrivial β
inhabited_h : Inhabited β
s : ι → Set α := fun i ↦ toMeasurable (μ i) {x | f x ≠ mk f ⋯ x}
hsμ : ∀ (i : ι), (μ i) (s i) = 0
hsm : MeasurableSet (⋂ i, s i)
i : ι
x : α
⊢ x ∉ s i → f x = mk f ⋯ x

Tactic:
hx

Goal state after:
ι : Type u_1
α : Type u_2
β : Type u_3
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
f : α → β
inst✝ : Countable ι
μ : ι → Measure α
h : ∀ (i : ι), AEMeasurable f (μ i)
a✝ : Nontrivial β
inhabited_h : Inhabited β
s : ι → Set α := fun i ↦ toMeasurable (μ i) {x | f x ≠ mk f ⋯ x}
hsμ : ∀ (i : ι), (μ i) (s i) = 0
hsm : MeasurableSet (⋂ i, s i)
i : ι
x : α
hx : x ∉ s i
⊢ f x = mk f ⋯ x
Module: Mathlib.MeasureTheory.MeasurableSpace.CountablyGenerated

Goal state before:
pp: case inr
β : Type u_2
α : Type u_3
γ : Type u_4
inst✝¹ : MeasurableSpace γ
inst✝ : Nonempty β
h✝ : CountableOrCountablyGenerated (α × β) γ
h : CountablyGenerated γ
⊢ CountableOrCountablyGenerated α γ

Tactic:
· infer_instance

Goal state after:
Module: Mathlib.MeasureTheory.MeasurableSpace.CountablyGenerated

Goal state before:
pp: case inr
β : Type u_2
α : Type u_3
γ : Type u_4
inst✝¹ : MeasurableSpace γ
inst✝ : Nonempty α
h✝ : CountableOrCountablyGenerated (α × β) γ
h : CountablyGenerated γ
⊢ CountableOrCountablyGenerated β γ

Tactic:
· infer_instance

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

Goal state before:
pp: α : Type u_2
β : Type u_3
m0 : MeasurableSpace α
inst✝ : MeasurableSpace β
f : α → β
μ : Measure α
H : AEMeasurable f μ
t : Set β
ht : ∀ᵐ (x : α) ∂μ, f x ∈ t
h₀ : t.Nonempty
s : Set α := toMeasurable μ {x | f x = mk f H x ∧ f x ∈ t}ᶜ
g : α → β := s.piecewise (fun x ↦ h₀.some) (mk f H)
A : μ (toMeasurable μ {x | f x = mk f H x ∧ f x ∈ t}ᶜ) = 0
x : α
⊢ x ∈ (toMeasurable μ {x | f x = mk f H x ∧ f x ∈ t}ᶜ)ᶜ → f x = g x

Tactic:
hx

Goal state after:
α : Type u_2
β : Type u_3
m0 : MeasurableSpace α
inst✝ : MeasurableSpace β
f : α → β
μ : Measure α
H : AEMeasurable f μ
t : Set β
ht : ∀ᵐ (x : α) ∂μ, f x ∈ t
h₀ : t.Nonempty
s : Set α := toMeasurable μ {x | f x = mk f H x ∧ f x ∈ t}ᶜ
g : α → β := s.piecewise (fun x ↦ h₀.some) (mk f H)
A : μ (toMeasurable μ {x | f x = mk f H x ∧ f x ∈ t}ᶜ) = 0
x : α
hx : x ∈ (toMeasurable μ {x | f x = mk f H x ∧ f x ∈ t}ᶜ)ᶜ
⊢ f x = g x
Module: Mathlib.MeasureTheory.Measure.AEMeasurable

Goal state before:
pp: α : Type u_2
β : Type u_3
m0 : MeasurableSpace α
inst✝ : MeasurableSpace β
f : α → β
μ : Measure α
h : AEMeasurable f μ
s : Set β
hfs : ∀ (x : α), f x ∈ s
a✝ : Nontrivial α
inhabited_h : Inhabited α
g : α → β
g_meas : Measurable g
hg : range g ⊆ s
fg : f =ᵐ[μ] g
x : α
⊢ f x = g x → codRestrict f s hfs x = codRestrict g s ⋯ x

Tactic:
hx

Goal state after:
α : Type u_2
β : Type u_3
m0 : MeasurableSpace α
inst✝ : MeasurableSpace β
f : α → β
μ : Measure α
h : AEMeasurable f μ
s : Set β
hfs : ∀ (x : α), f x ∈ s
a✝ : Nontrivial α
inhabited_h : Inhabited α
g : α → β
g_meas : Measurable g
hg : range g ⊆ s
fg : f =ᵐ[μ] g
x : α
hx : f x = g x
⊢ codRestrict f s hfs x = codRestrict g s ⋯ x
Module: Mathlib.MeasureTheory.Measure.MeasureSpace

Goal state before:
pp: α : Type u_1
ι : Type u_5
m0 : MeasurableSpace α
s : Set ι
μ : ι → Measure α
t : Set α
ht : MeasurableSet t
⊢ ∑' (i : ↑s), (μ ↑i) t + ∑' (i : ↑sᶜ), (μ ↑i) t = ∑' (i : ι), (μ i) t

Tactic:
exact ENNReal.summable.tsum_add_tsum_compl (f := fun i => μ i t) ENNReal.summable

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s : Set α
r : ℝ≥0∞
h : r < infEDist x s
y : α
hy : edist y x ≤ r
h'y : y ∈ s
⊢ edist x y ≤ r

Tactic:
edist_comm

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s : Set α
r : ℝ≥0∞
h : r < infEDist x s
y : α
hy : edist x y ≤ r
h'y : y ∈ s
⊢ edist x y ≤ r
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s : Set α
r : ℝ≥0∞
h : r < infEDist x s
⊢ Disjoint (closedEBall x r) s

Tactic:
by
  rw [disjoint_left]
  intro y hy h'y
  apply lt_irrefl (infEDist x s)
  calc
    infEDist x s ≤ edist x y := infEDist_le_edist_of_mem h'y
    _ ≤ r := by rwa [Metric.mem_closedEBall, edist_comm] at hy
    _ < infEDist x s := h

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: case refine_2
α : Type u
inst✝ : PseudoEMetricSpace α
U : Set α
hU : IsOpen[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] U
a : ℝ≥0∞
a_pos : 0 < a
a_lt_one : a < 1
F : ℕ → Set α := fun n ↦ (fun x ↦ infEDist x Uᶜ) ⁻¹' Ici (a ^ n)
F_subset : ∀ (n : ℕ), F n ⊆ U
m n : ℕ
hmn : m ≤ n
x : α
⊢ x ∈ F m → x ∈ F n

Tactic:
hx

Goal state after:
case refine_2
α : Type u
inst✝ : PseudoEMetricSpace α
U : Set α
hU : IsOpen[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] U
a : ℝ≥0∞
a_pos : 0 < a
a_lt_one : a < 1
F : ℕ → Set α := fun n ↦ (fun x ↦ infEDist x Uᶜ) ⁻¹' Ici (a ^ n)
F_subset : ∀ (n : ℕ), F n ⊆ U
m n : ℕ
hmn : m ≤ n
x : α
hx : x ∈ F m
⊢ x ∈ F n
Module: Mathlib.MeasureTheory.Constructions.BorelSpace.Basic

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s t u : Set α
inst✝¹² : TopologicalSpace α
inst✝¹¹ : MeasurableSpace α
inst✝¹⁰ : OpensMeasurableSpace α
inst✝⁹ : TopologicalSpace β
inst✝⁸ : MeasurableSpace β
inst✝⁷ : OpensMeasurableSpace β
inst✝⁶ : TopologicalSpace γ
inst✝⁵ : MeasurableSpace γ
inst✝⁴ : BorelSpace γ
inst✝³ : TopologicalSpace γ₂
inst✝² : MeasurableSpace γ₂
inst✝¹ : BorelSpace γ₂
inst✝ : MeasurableSpace δ
h : SecondCountableTopologyEither α β
⊢ OpensMeasurableSpace (α × β)

Tactic:
by
  apply opensMeasurableSpace_iff_forall_measurableSet.2 (fun s hs ↦ ?_)
  rcases h.out with hα | hβ
  · let F : Set α → Set β := fun a ↦ {y | ∃ b, IsOpen b ∧ y ∈ b ∧ a ×ˢ b ⊆ s}
    have A : ∀ a, IsOpen (F a) := by
      intro a
      apply isOpen_iff_forall_mem_open.2
      rintro y ⟨b, b_open, yb, hb⟩
      exact ⟨b, fun z zb ↦ ⟨b, b_open, zb, hb⟩, b_open, yb⟩
    have : s = ⋃ a ∈ countableBasis α, a ×ˢ F a := by
      apply Subset.antisymm
      · rintro ⟨y1, y2⟩ hy
        rcases isOpen_prod_iff.1 hs y1 y2 hy with ⟨u, v, u_open, v_open, yu, yv, huv⟩
        obtain ⟨a, ha, ya, au⟩ : ∃ a ∈ countableBasis α, y1 ∈ a ∧ a ⊆ u :=
          IsTopologicalBasis.exists_subset_of_mem_open (isBasis_countableBasis α) yu u_open
        simp only [mem_iUnion, mem_prod, exists_and_left, exists_prop]
        exact ⟨a, ya, ha, v, v_open, yv, (Set.prod_mono_left au).trans huv⟩
      · rintro ⟨y1, y2⟩ hy
        simp only [mem_iUnion, mem_prod, exists_and_left, exists_prop] at hy
        rcases hy with ⟨a, ya, -, b, -, yb, hb⟩
        exact hb (mem_prod.2 ⟨ya, yb⟩)
    rw [this]
    apply MeasurableSet.biUnion (countable_countableBasis α) (fun a ha ↦ ?_)
    exact (isOpen_of_mem_countableBasis ha).measurableSet.prod (A a).measurableSet
  · let F : Set β → Set α := fun a ↦ {y | ∃ b, IsOpen b ∧ y ∈ b ∧ b ×ˢ a ⊆ s}
    have A : ∀ a, IsOpen (F a) := by
      intro a
      apply isOpen_iff_forall_mem_open.2
      rintro y ⟨b, b_open, yb, hb⟩
      exact ⟨b, fun z zb ↦ ⟨b, b_open, zb, hb⟩, b_open, yb⟩
    have : s = ⋃ a ∈ countableBasis β, F a ×ˢ a := by
      apply Subset.antisymm
      · rintro ⟨y1, y2⟩ hy
        rcases isOpen_prod_iff.1 hs y1 y2 hy with ⟨u, v, u_open, v_open, yu, yv, huv⟩
        obtain ⟨a, ha, ya, au⟩ : ∃ a ∈ countableBasis β, y2 ∈ a ∧ a ⊆ v :=
          IsTopologicalBasis.exists_subset_of_mem_open (isBasis_countableBasis β) yv v_open
        simp only [mem_iUnion, mem_prod, exists_and_left, exists_prop]
        exact ⟨a, ⟨u, u_open, yu, (Set.prod_mono_right au).trans huv⟩, ha, ya⟩
      · rintro ⟨y1, y2⟩ hy
        simp only [mem_iUnion, mem_prod, exists_and_left, exists_prop] at hy
        rcases hy with ⟨a, ⟨b, -, yb, hb⟩, -, ya⟩
        exact hb (mem_prod.2 ⟨yb, ya⟩)
    rw [this]
    apply MeasurableSet.biUnion (countable_countableBasis β) (fun a ha ↦ ?_)
    exact (A a).measurableSet.prod (isOpen_of_mem_countableBasis ha).measurableSet

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
x y : α
⊢ max (edist x y) (edist y x) = edist x y

Tactic:
edist_comm

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
x y : α
⊢ max (edist x y) (edist x y) = edist x y
Module: Mathlib.MeasureTheory.Constructions.BorelSpace.Order

Goal state before:
pp: α : Type u_5
inst✝³ : TopologicalSpace α
inst✝² : LinearOrder α
inst✝¹ : OrderTopology α
inst✝ : SecondCountableTopology α
s : Set α
hd : Dense s
hbot : ∀ (x : α), IsBot x → x ∈ s
hIoo : ∀ (x y : α), x < y → Ioo x y = ∅ → y ∈ s
S : Set (Set α) := {S | ∃ l ∈ s, ∃ u ∈ s, l < u ∧ Ico l u = S}
this : MeasurableSpace α := MeasurableSpace.generateFrom S
a : α
t : Set α
hts : t ⊆ s
hc : t.Countable
htd : Dense t
htb : ∀ (x : α), IsBot x → x ∈ s → x ∈ t
ha : a ∈ s
x : α
⊢ x < a → ∃ i, ∃ (_ : i ∈ t) (_ : i < a), i ≤ x

Tactic:
hx

Goal state after:
α : Type u_5
inst✝³ : TopologicalSpace α
inst✝² : LinearOrder α
inst✝¹ : OrderTopology α
inst✝ : SecondCountableTopology α
s : Set α
hd : Dense s
hbot : ∀ (x : α), IsBot x → x ∈ s
hIoo : ∀ (x y : α), x < y → Ioo x y = ∅ → y ∈ s
S : Set (Set α) := {S | ∃ l ∈ s, ∃ u ∈ s, l < u ∧ Ico l u = S}
this : MeasurableSpace α := MeasurableSpace.generateFrom S
a : α
t : Set α
hts : t ⊆ s
hc : t.Countable
htd : Dense t
htb : ∀ (x : α), IsBot x → x ∈ s → x ∈ t
ha : a ∈ s
x : α
hx : x < a
⊢ ∃ i, ∃ (_ : i ∈ t) (_ : i < a), i ≤ x
Module: Mathlib.Topology.MetricSpace.Thickening

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
E : Set α
x : α
⊢ x ∈ thickening δ E → x ∈ cthickening δ E

Tactic:
hx

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
E : Set α
x : α
hx : x ∈ thickening δ E
⊢ x ∈ cthickening δ E
Module: Mathlib.Topology.MetricSpace.Thickening

Goal state before:
pp: case h₂
α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
s : Set ℝ
hsδ : s ⊆ Ioi δ
hs : ∀ (ε : ℝ), δ < ε → (s ∩ Ioc δ ε).Nonempty
E : Set α
x : α
⊢ x ∈ ⋂ ε ∈ s, {x | infEDist x E ≤ ENNReal.ofReal ε} → x ∈ {x | infEDist x E ≤ ENNReal.ofReal δ}

Tactic:
hx

Goal state after:
case h₂
α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
s : Set ℝ
hsδ : s ⊆ Ioi δ
hs : ∀ (ε : ℝ), δ < ε → (s ∩ Ioc δ ε).Nonempty
E : Set α
x : α
hx : x ∈ ⋂ ε ∈ s, {x | infEDist x E ≤ ENNReal.ofReal ε}
⊢ x ∈ {x | infEDist x E ≤ ENNReal.ofReal δ}
Module: Mathlib.Topology.MetricSpace.Thickening

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
s : Set α
x : α
r : ℝ≥0∞
h : ∃ y ∈ cthickening δ s, edist x y < r - ENNReal.ofReal δ
⊢ infEDist x s < r

Tactic:
mem_cthickening_iff

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
s : Set α
x : α
r : ℝ≥0∞
h : ∃ y, infEDist y s ≤ ENNReal.ofReal δ ∧ edist x y < r - ENNReal.ofReal δ
⊢ infEDist x s < r
Module: Mathlib.Topology.MetricSpace.Thickening

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
δ ε : ℝ
hδ : 0 ≤ δ
s : Set α
⊢ thickening ε (cthickening δ s) ⊆ thickening (ε + δ) s

Tactic:
by
  obtain hε | hε := le_total ε 0
  · simp only [thickening_of_nonpos hε, empty_subset]
  intro x
  simp_rw [mem_thickening_iff_exists_edist_lt, mem_cthickening_iff, ← infEDist_lt_iff,
    ENNReal.ofReal_add hε hδ]
  rintro ⟨y, hy, hxy⟩
  exact infEDist_le_edist_add_infEDist.trans_lt
    (ENNReal.add_lt_add_of_lt_of_le (hy.trans_lt ENNReal.ofReal_lt_top).ne hxy hy)

Goal state after:
Module: Mathlib.Topology.MetricSpace.Thickening

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
ε : ℝ
hε : 0 ≤ ε
δ : ℝ
s : Set α
hδ : 0 ≤ δ
x : α
hx : infEDist x (thickening δ s) ≤ ENNReal.ofReal ε
⊢ infEDist x (thickening (?m.52 hx) s) + ENNReal.ofReal (?m.52 hx) ≤ ENNReal.ofReal ε + ENNReal.ofReal δ

Tactic:
hx

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
ε : ℝ
hε : 0 ≤ ε
δ : ℝ
s : Set α
hδ : 0 ≤ δ
x : α
hx : infEDist x (thickening δ s) ≤ ENNReal.ofReal ε
⊢ ENNReal.ofReal ε + ENNReal.ofReal δ ≤ ENNReal.ofReal ε + ENNReal.ofReal δ
Module: Mathlib.Topology.MetricSpace.Thickening

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
δ ε : ℝ
hε : 0 ≤ ε
hδ : 0 ≤ δ
s : Set α
x : α
hx : infEDist x (cthickening δ s) ≤ ENNReal.ofReal ε
⊢ infEDist x (cthickening (?m.38 hx) s) + ENNReal.ofReal (?m.38 hx) ≤ ENNReal.ofReal ε + ENNReal.ofReal δ

Tactic:
hx

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
δ ε : ℝ
hε : 0 ≤ ε
hδ : 0 ≤ δ
s : Set α
x : α
hx : infEDist x (cthickening δ s) ≤ ENNReal.ofReal ε
⊢ ENNReal.ofReal ε + ENNReal.ofReal δ ≤ ENNReal.ofReal ε + ENNReal.ofReal δ
Module: Mathlib.MeasureTheory.MeasurableSpace.Prod

Goal state before:
pp: α : Type u_1
inst✝¹ : MeasurableSpace α
β : Type u_3
γ : Type u_4
inst✝ : MeasurableSingletonClass α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
x : α
f : γ → β
hf : MeasurableEmbedding f
y y' : γ
⊢ f y = f y' → y = y'

Tactic:
exact fun h ↦ hf.injective h

Goal state after: