mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Topology.UnitInterval

Goal state before:
pp: a b : ℝ
x y z : ↑(Icc a b)
s t : ↑unitInterval
⊢ convexComb x (convexComb y z t) s =
    convexComb (convexComb x y (convexComb_assoc_coeff₁ s t)) z (convexComb_assoc_coeff₂ s t)

Tactic:
simp only [convexComb, coe_mul, Subtype.mk.injEq]
  by_cases hs : (s : ℝ) = 1
  · simp only [hs]
    by_cases ht : (t : ℝ) = 1
    · simp [ht]
    · have : (1 - t : ℝ) ≠ 0 := by grind
      field_simp
      simp
  · by_cases ht : (t : ℝ) = 1
    · simp [ht]
    · have : (1 - s * t : ℝ) ≠ 0 := by
        intro h
        have : 1 ≤ (t : ℝ) := by nlinarith [s.2.2, t.2.1]
        grind
      field_simp
      ring_nf

Goal state after:
Module: Mathlib.Topology.UnitInterval

Goal state before:
pp: a b : ℝ
x y z : ↑(Icc a b)
s t : ↑unitInterval
⊢ convexComb x (convexComb z y (convexComb_assoc_coeff₁ (unitInterval.symm t) (unitInterval.symm s)))
      (unitInterval.symm (convexComb_assoc_coeff₂ (unitInterval.symm t) (unitInterval.symm s))) =
    convexComb x (convexComb z y (unitInterval.symm (convexComb_assoc_coeff₂' s t)))
      (unitInterval.symm (convexComb_assoc_coeff₂ (unitInterval.symm t) (unitInterval.symm s)))

Tactic:
convexComb_assoc_coeff₂',

Goal state after:
a b : ℝ
x y z : ↑(Icc a b)
s t : ↑unitInterval
⊢ convexComb x (convexComb z y (convexComb_assoc_coeff₁ (unitInterval.symm t) (unitInterval.symm s)))
      (unitInterval.symm (convexComb_assoc_coeff₂ (unitInterval.symm t) (unitInterval.symm s))) =
    convexComb x
      (convexComb z y
        (unitInterval.symm (unitInterval.symm (convexComb_assoc_coeff₁ (unitInterval.symm t) (unitInterval.symm s)))))
      (unitInterval.symm (convexComb_assoc_coeff₂ (unitInterval.symm t) (unitInterval.symm s)))
Module: Mathlib.Topology.MetricSpace.PiNat

Goal state before:
pp: E : ℕ → Type u_1
x : (n : ℕ) → E n
⊢ dist x x = 0

Tactic:
by simp [dist]

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

Goal state before:
pp: E : ℕ → Type u_1
inst✝¹ : (n : ℕ) → TopologicalSpace (E n)
inst✝ : ∀ (n : ℕ), DiscreteTopology (E n)
x : (n : ℕ) → E n
n : ℕ
⊢ IsOpen[Pi.topologicalSpace] (cylinder x n)

Tactic:
by
  rw [PiNat.cylinder_eq_pi]
  exact isOpen_set_pi (Finset.range n).finite_toSet fun a _ => isOpen_discrete _

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

Goal state before:
pp: β : Type u_1
α : Type u_2
A : List β → Set α
inst✝¹ : PseudoMetricSpace α
inst✝ : CompleteSpace α
hdiam : VanishingDiam A
hanti : ClosureAntitone A
hnonempty : ∀ (l : List β), (A l).Nonempty
x : ℕ → β
u : ℕ → α
hu : ∀ (n : ℕ), u n ∈ A (res x n)
this : Antitone fun n ↦ A (res x n)
⊢ ∀ (n m : ℕ), n ≤ m → u m ∈ A (res x n)

Tactic:
intro n m hnm

Goal state after:
β : Type u_1
α : Type u_2
A : List β → Set α
inst✝¹ : PseudoMetricSpace α
inst✝ : CompleteSpace α
hdiam : VanishingDiam A
hanti : ClosureAntitone A
hnonempty : ∀ (l : List β), (A l).Nonempty
x : ℕ → β
u : ℕ → α
hu : ∀ (n : ℕ), u n ∈ A (res x n)
this : Antitone fun n ↦ A (res x n)
n m : ℕ
hnm : n ≤ m
⊢ u m ∈ A (res x n)
Module: Mathlib.Topology.MetricSpace.CantorScheme

Goal state before:
pp: case h
β : Type u_1
α : Type u_2
A : List β → Set α
inst✝¹ : PseudoMetricSpace α
inst✝ : CompleteSpace α
hdiam : VanishingDiam A
hanti : ClosureAntitone A
hnonempty : ∀ (l : List β), (A l).Nonempty
x : ℕ → β
u : ℕ → α
hu : ∀ (n : ℕ), u n ∈ A (res x n)
umem : ∀ (n m : ℕ), n ≤ m → u m ∈ A (res x n)
ε : ℝ
ε_pos : ε > 0
n : ℕ
hn : ∀ y ∈ A (res x n), ∀ z ∈ A (res x n), dist y z < ε
m₀ : ℕ
hm₀ : m₀ ≥ n
⊢ ∀ n_1 ≥ n, dist (u m₀) (u n_1) < ε

Tactic:
m₁

Goal state after:
case h
β : Type u_1
α : Type u_2
A : List β → Set α
inst✝¹ : PseudoMetricSpace α
inst✝ : CompleteSpace α
hdiam : VanishingDiam A
hanti : ClosureAntitone A
hnonempty : ∀ (l : List β), (A l).Nonempty
x : ℕ → β
u : ℕ → α
hu : ∀ (n : ℕ), u n ∈ A (res x n)
umem : ∀ (n m : ℕ), n ≤ m → u m ∈ A (res x n)
ε : ℝ
ε_pos : ε > 0
n : ℕ
hn : ∀ y ∈ A (res x n), ∀ z ∈ A (res x n), dist y z < ε
m₀ : ℕ
hm₀ : m₀ ≥ n
m₁ : ℕ
⊢ m₁ ≥ n → dist (u m₀) (u m₁) < ε
Module: Mathlib.Topology.MetricSpace.CantorScheme

Goal state before:
pp: case h.x
β : Type u_1
α : Type u_2
A : List β → Set α
inst✝¹ : PseudoMetricSpace α
inst✝ : CompleteSpace α
hdiam : VanishingDiam A
hanti : ClosureAntitone A
hnonempty : ∀ (l : List β), (A l).Nonempty
x : ℕ → β
u : ℕ → α
hu : ∀ (n : ℕ), u n ∈ A (res x n)
umem : ∀ (n m : ℕ), n ≤ m → u m ∈ A (res x n)
ε : ℝ
ε_pos : ε > 0
n : ℕ
hn : ∀ y ∈ A (res x n), ∀ z ∈ A (res x n), dist y z < ε
m₀ : ℕ
hm₀ : m₀ ≥ n
m₁ : ℕ
hm₁ : m₁ ≥ n
⊢ n ≤ m₀

Tactic:
assumption

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

Goal state before:
pp: case h.x
β : Type u_1
α : Type u_2
A : List β → Set α
inst✝¹ : PseudoMetricSpace α
inst✝ : CompleteSpace α
hdiam : VanishingDiam A
hanti : ClosureAntitone A
hnonempty : ∀ (l : List β), (A l).Nonempty
x : ℕ → β
u : ℕ → α
hu : ∀ (n : ℕ), u n ∈ A (res x n)
umem : ∀ (n m : ℕ), n ≤ m → u m ∈ A (res x n)
ε : ℝ
ε_pos : ε > 0
n : ℕ
hn : ∀ y ∈ A (res x n), ∀ z ∈ A (res x n), dist y z < ε
m₀ : ℕ
hm₀ : m₀ ≥ n
m₁ : ℕ
hm₁ : m₁ ≥ n
⊢ n ≤ m₁

Tactic:
assumption

Goal state after:
Module: Mathlib.Topology.Separation.CountableSeparatingOn

Goal state before:
pp: X : Type u_1
inst✝² : TopologicalSpace X
s : Set X
inst✝¹ : T0Space ↑s
inst✝ : SecondCountableTopology ↑s
⊢ HasCountableSeparatingOn X IsOpen s

Tactic:
suffices HasCountableSeparatingOn s IsOpen univ from .of_subtype fun _ ↦ isOpen_induced_iff.1
  refine ⟨⟨countableBasis s, countable_countableBasis _, fun _ ↦ isOpen_of_mem_countableBasis,
    fun x _ y _ h ↦ ?_⟩⟩
  exact ((isBasis_countableBasis _).inseparable_iff.2 h).eq

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

Goal state before:
pp: α : Type u_1
inst✝ : MetricSpace α
C : Set α
ε : ℝ≥0∞
hC : Perfect C
hnonempty : C.Nonempty
ε_pos : 0 < ε
D₀ D₁ : Set α
perf0 : Perfect D₀
sub0 : D₀ ⊆ C
hdisj : Disjoint D₀ D₁
perf1 : Perfect D₁
sub1 : D₁ ⊆ C
x₀ : α
hx₀ : x₀ ∈ D₀
x₁ : α
hx₁ : x₁ ∈ D₁
perf0' : Perfect (closure (eball x₀ (ε / 2) ∩ D₀))
non0' : (closure (eball x₀ (ε / 2) ∩ D₀)).Nonempty
sub0' : closure (eball x₀ (ε / 2) ∩ D₀) ⊆ D₀
diam0 : ediam (closure (eball x₀ (ε / 2) ∩ D₀)) ≤ ε
perf1' : Perfect (closure (eball x₁ (ε / 2) ∩ D₁))
non1' : (closure (eball x₁ (ε / 2) ∩ D₁)).Nonempty
sub1' : closure (eball x₁ (ε / 2) ∩ D₁) ⊆ D₁
diam1 : ediam (closure (eball x₁ (ε / 2) ∩ D₁)) ≤ ε
⊢ closure (eball x₀ (ε / 2) ∩ D₀) ⊆ D₀

Tactic:
assumption

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

Goal state before:
pp: α : Type u_1
inst✝ : MetricSpace α
C : Set α
ε : ℝ≥0∞
hC : Perfect C
hnonempty : C.Nonempty
ε_pos : 0 < ε
D₀ D₁ : Set α
perf0 : Perfect D₀
sub0 : D₀ ⊆ C
hdisj : Disjoint D₀ D₁
perf1 : Perfect D₁
sub1 : D₁ ⊆ C
x₀ : α
hx₀ : x₀ ∈ D₀
x₁ : α
hx₁ : x₁ ∈ D₁
perf0' : Perfect (closure (eball x₀ (ε / 2) ∩ D₀))
non0' : (closure (eball x₀ (ε / 2) ∩ D₀)).Nonempty
sub0' : closure (eball x₀ (ε / 2) ∩ D₀) ⊆ D₀
diam0 : ediam (closure (eball x₀ (ε / 2) ∩ D₀)) ≤ ε
perf1' : Perfect (closure (eball x₁ (ε / 2) ∩ D₁))
non1' : (closure (eball x₁ (ε / 2) ∩ D₁)).Nonempty
sub1' : closure (eball x₁ (ε / 2) ∩ D₁) ⊆ D₁
diam1 : ediam (closure (eball x₁ (ε / 2) ∩ D₁)) ≤ ε
⊢ closure (eball x₁ (ε / 2) ∩ D₁) ⊆ D₁

Tactic:
assumption

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

Goal state before:
pp: E : ℕ → Type u_1
inst✝¹ : (n : ℕ) → TopologicalSpace (E n)
inst✝ : ∀ (n : ℕ), DiscreteTopology (E n)
s : Set ((n : ℕ) → E n)
hs : IsClosed[Pi.topologicalSpace] s
hne : s.Nonempty
f : ((n : ℕ) → E n) → (n : ℕ) → E n := fun x ↦ if x ∈ s then x else ⋯.some
⊢ ∃ f, (∀ x ∈ s, f x = x) ∧ range f = s ∧ LipschitzWith 1 f

Tactic:
have fs : ∀ x ∈ s, f x = x := fun x xs => by simp [f, xs]

Goal state after:
E : ℕ → Type u_1
inst✝¹ : (n : ℕ) → TopologicalSpace (E n)
inst✝ : ∀ (n : ℕ), DiscreteTopology (E n)
s : Set ((n : ℕ) → E n)
hs : IsClosed[Pi.topologicalSpace] s
hne : s.Nonempty
f : ((n : ℕ) → E n) → (n : ℕ) → E n := fun x ↦ if x ∈ s then x else ⋯.some
fs : ∀ x ∈ s, f x = x
⊢ ∃ f, (∀ x ∈ s, f x = x) ∧ range f = s ∧ LipschitzWith 1 f
Module: Mathlib.MeasureTheory.Integral.Lebesgue.Map

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSpace β
μ : Measure α
g : α → β
hg : MeasurableEmbedding g
f : β → ℝ≥0∞
⊢ ⨆ g_1, ⨆ (_ : ⇑g_1 ≤ fun a ↦ f a), g_1.lintegral (Measure.map g μ) =
    ⨆ g_1, ⨆ (_ : ⇑g_1 ≤ fun a ↦ f (g a)), g_1.lintegral μ

Tactic:
refine le_antisymm (iSup₂_le fun f₀ hf₀ => ?_) (iSup₂_le fun f₀ hf₀ => ?_)

Goal state after:
case refine_1
α : Type u_1
β : Type u_2
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSpace β
μ : Measure α
g : α → β
hg : MeasurableEmbedding g
f : β → ℝ≥0∞
f₀ : SimpleFunc β ℝ≥0∞
hf₀ : ⇑f₀ ≤ fun a ↦ f a
⊢ f₀.lintegral (Measure.map g μ) ≤ ⨆ g_1, ⨆ (_ : ⇑g_1 ≤ fun a ↦ f (g a)), g_1.lintegral μ

case refine_2
α : Type u_1
β : Type u_2
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSpace β
μ : Measure α
g : α → β
hg : MeasurableEmbedding g
f : β → ℝ≥0∞
f₀ : SimpleFunc α ℝ≥0∞
hf₀ : ⇑f₀ ≤ fun a ↦ f (g a)
⊢ f₀.lintegral μ ≤ ⨆ g_1, ⨆ (_ : ⇑g_1 ≤ fun a ↦ f a), g_1.lintegral (Measure.map g μ)
Module: Mathlib.MeasureTheory.Constructions.Polish.Basic

Goal state before:
pp: α : Type u_1
inst✝ : TopologicalSpace α
⊢ AnalyticSet ∅

Tactic:
by
  rw [AnalyticSet]
  exact Or.inl rfl

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

Goal state before:
pp: α : Type u_1
inst✝¹ : MetricSpace α
C : Set α
hC : Perfect C
hnonempty : C.Nonempty
inst✝ : CompleteSpace α
⊢ ∃ f, range f ⊆ C ∧ Continuous f ∧ Injective f

Tactic:
obtain ⟨u, -, upos', hu⟩ := exists_seq_strictAnti_tendsto' (zero_lt_one' ℝ≥0∞)
  have upos := fun n => (upos' n).1
  let P := Subtype fun E : Set α => Perfect E ∧ E.Nonempty
  choose C0 C1 h0 h1 hdisj using
    fun {C : Set α} (hC : Perfect C) (hnonempty : C.Nonempty) {ε : ℝ≥0∞} (hε : 0 < ε) =>
    hC.small_diam_splitting hnonempty hε
  let DP : List Bool → P := fun l => by
    induction l with
    | nil => exact ⟨C, ⟨hC, hnonempty⟩⟩
    | cons a l ih =>
      cases a
      · use C0 ih.property.1 ih.property.2 (upos (l.length + 1))
        exact ⟨(h0 _ _ _).1, (h0 _ _ _).2.1⟩
      use C1 ih.property.1 ih.property.2 (upos (l.length + 1))
      exact ⟨(h1 _ _ _).1, (h1 _ _ _).2.1⟩
  let D : List Bool → Set α := fun l => (DP l).val
  have hanti : ClosureAntitone D := by
    refine Antitone.closureAntitone ?_ fun l => (DP l).property.1.closed
    intro l a
    cases a
    · exact (h0 _ _ _).2.2.1
    exact (h1 _ _ _).2.2.1
  have hdiam : VanishingDiam D := by
    intro x
    apply tendsto_of_tendsto_of_tendsto_of_le_of_le' tendsto_const_nhds hu
    · simp
    rw [eventually_atTop]
    refine ⟨1, fun m (hm : 1 ≤ m) => ?_⟩
    rw [Nat.one_le_iff_ne_zero] at hm
    rcases Nat.exists_eq_succ_of_ne_zero hm with ⟨n, rfl⟩
    dsimp
    cases x n
    · convert! (h0 _ _ _).2.2.2
      rw [PiNat.res_length]
    convert! (h1 _ _ _).2.2.2
    rw [PiNat.res_length]
  have hdisj' : CantorScheme.Disjoint D := by
    rintro l (a | a) (b | b) hab <;> try contradiction
    · exact hdisj _ _ _
    exact (hdisj _ _ _).symm
  have hdom : ∀ {x : ℕ → Bool}, x ∈ (inducedMap D).1 := fun {x} => by
    rw [hanti.map_of_vanishingDiam hdiam fun l => (DP l).property.2]
    apply mem_univ
  refine ⟨fun x => (inducedMap D).2 ⟨x, hdom⟩, ?_, ?_, ?_⟩
  · rintro y ⟨x, rfl⟩
    exact map_mem ⟨_, hdom⟩ 0
  · apply hdiam.map_continuous.comp
    fun_prop
  intro x y hxy
  simpa only [← Subtype.val_inj] using hdisj'.map_injective hxy

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

Goal state before:
pp: case pos
α : Type u_1
inst✝¹ : MeasurableSpace α
s : Set α
a : α
hs : MeasurableSet s
inst✝ : Decidable (a ∈ s)
has : a ∈ s
⊢ a ∈ s

Tactic:
assumption

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

Goal state before:
pp: case pos
α : Type u_1
inst✝¹ : MeasurableSpace α
s : Set α
a : α
hs : MeasurableSet s
inst✝ : Decidable (a ∈ s)
has : a ∈ s
⊢ MeasurableSet {x | x ∈ s}

Tactic:
assumption

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

Goal state before:
pp: α : Type u_1
mα : MeasurableSpace α
m : Measure (Measure α)
s : Set α
⊢ ∫⁻ (μ : Measure α), μ s ∂m ≤ m.join s

Tactic:
measure_eq_iInf

Goal state after:
α : Type u_1
mα : MeasurableSpace α
m : Measure (Measure α)
s : Set α
⊢ ∫⁻ (μ : Measure α), μ s ∂m ≤ ⨅ t, ⨅ (_ : s ⊆ t), ⨅ (_ : MeasurableSet t), m.join t
Module: Mathlib.MeasureTheory.Measure.GiryMonad

Goal state before:
pp: α : Type u_1
mα : MeasurableSpace α
⊢ join 0 = 0

Tactic:
ext1 s hs
  simp [hs]

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

Goal state before:
pp: α : Type u_1
mα : MeasurableSpace α
μ : Measure (Measure (Measure α))
⊢ (map join μ).join = μ.join.join

Tactic:
by
  change bind μ join = join (join μ)
  rw [join_eq_bind, join_eq_bind, bind_bind aemeasurable_id aemeasurable_id]
  apply congr_arg (bind μ)
  funext ν
  exact join_eq_bind ν

Goal state after:
Module: Mathlib.MeasureTheory.Group.Convolution

Goal state before:
pp: M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
⊢ ∫⁻ (a : M), f a ∂(μ ∗ₘ ν) ∗ₘ ρ = ∫⁻ (a : M), f a ∂μ ∗ₘ ν ∗ₘ ρ

Tactic:
rw [lintegral_mconv (by fun_prop)]

Goal state after:
M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
⊢ ∫⁻ (x : M), ∫⁻ (y : M), f (x * y) ∂ρ ∂μ ∗ₘ ν = ∫⁻ (a : M), f a ∂μ ∗ₘ ν ∗ₘ ρ
Module: Mathlib.MeasureTheory.Group.Convolution

Goal state before:
pp: M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
⊢ ∫⁻ (x : M), ∫⁻ (y : M), f (x * y) ∂ρ ∂μ ∗ₘ ν = ∫⁻ (a : M), f a ∂μ ∗ₘ ν ∗ₘ ρ

Tactic:
rw [lintegral_mconv (by fun_prop)]

Goal state after:
M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
⊢ ∫⁻ (x : M), ∫⁻ (y : M), ∫⁻ (y_1 : M), f (x * y * y_1) ∂ρ ∂ν ∂μ = ∫⁻ (a : M), f a ∂μ ∗ₘ ν ∗ₘ ρ
Module: Mathlib.MeasureTheory.Group.Convolution

Goal state before:
pp: M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
⊢ ∫⁻ (x : M), ∫⁻ (y : M), ∫⁻ (y_1 : M), f (x * y * y_1) ∂ρ ∂ν ∂μ = ∫⁻ (a : M), f a ∂μ ∗ₘ ν ∗ₘ ρ

Tactic:
rw [lintegral_mconv (by fun_prop)]

Goal state after:
M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
⊢ ∫⁻ (x : M), ∫⁻ (y : M), ∫⁻ (y_1 : M), f (x * y * y_1) ∂ρ ∂ν ∂μ = ∫⁻ (x : M), ∫⁻ (y : M), f (x * y) ∂ν ∗ₘ ρ ∂μ
Module: Mathlib.MeasureTheory.Group.Convolution

Goal state before:
pp: M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
⊢ ∫⁻ (x : M), ∫⁻ (y : M), ∫⁻ (y_1 : M), f (x * y * y_1) ∂ρ ∂ν ∂μ = ∫⁻ (x : M), ∫⁻ (y : M), f (x * y) ∂ν ∗ₘ ρ ∂μ

Tactic:
rw [lintegral_mconv (by fun_prop)]

Goal state after:
M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
⊢ ∫⁻ (x : M), ∫⁻ (y : M), ∫⁻ (y_1 : M), f (x * y * y_1) ∂ρ ∂ν ∂μ = ∫⁻ (x : M), ∫⁻ (y : M), f (x * y) ∂ν ∗ₘ ρ ∂μ
Module: Mathlib.MeasureTheory.Group.Convolution

Goal state before:
pp: M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
x : M
⊢ ∫⁻ (y : M), ∫⁻ (y_1 : M), f (x * y * y_1) ∂ρ ∂ν = ∫⁻ (y : M), f (x * y) ∂ν ∗ₘ ρ

Tactic:
rw [lintegral_mconv (by fun_prop)]

Goal state after:
M : Type u_1
inst✝⁴ : Monoid M
inst✝³ : MeasurableSpace M
inst✝² : MeasurableMul₂ M
μ ν ρ : Measure M
inst✝¹ : SFinite ν
inst✝ : SFinite ρ
f : M → ℝ≥0∞
hf : Measurable f
x : M
⊢ ∫⁻ (y : M), ∫⁻ (y_1 : M), f (x * y * y_1) ∂ρ ∂ν = ∫⁻ (x_1 : M), ∫⁻ (y : M), f (x * (x_1 * y)) ∂ρ ∂ν
Module: Mathlib.MeasureTheory.Measure.Prod

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : MeasurableSpace α
inst✝¹ : MeasurableSpace β
μ : Measure α
ν : Measure β
inst✝ : SFinite ν
s : Set α
t : Set β
ST : Set (α × β) := toMeasurable (μ.prod ν) (s ×ˢ t)
hSTm : MeasurableSet ST
hST : s ×ˢ t ⊆ ST
⊢ μ s * ν t ≤ (μ.prod ν) (s ×ˢ t)

Tactic:
set f : α → ℝ≥0∞ := fun x => ν (Prod.mk x ⁻¹' ST)

Goal state after:
α : Type u_1
β : Type u_2
inst✝² : MeasurableSpace α
inst✝¹ : MeasurableSpace β
μ : Measure α
ν : Measure β
inst✝ : SFinite ν
s : Set α
t : Set β
ST : Set (α × β) := toMeasurable (μ.prod ν) (s ×ˢ t)
hSTm : MeasurableSet ST
hST : s ×ˢ t ⊆ ST
f : α → ℝ≥0∞ := fun x ↦ ν (Prod.mk x ⁻¹' ST)
⊢ μ s * ν t ≤ (μ.prod ν) (s ×ˢ t)
Module: Mathlib.MeasureTheory.Measure.Prod

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝³ : MeasurableSpace α
inst✝² : MeasurableSpace β
ι' : Type u_4
inst✝¹ : Countable ι'
m : Measure α
m' : ι' → Measure β
inst✝ : ∀ (n : ι'), SFinite (m' n)
s : Set (α × β)
hs : MeasurableSet s
⊢ (m.prod (sum m')) s = (sum fun p ↦ m.prod (m' p)) s

Tactic:
simp only [prod_apply hs, hs, sum_apply]

Goal state after:
α : Type u_1
β : Type u_2
inst✝³ : MeasurableSpace α
inst✝² : MeasurableSpace β
ι' : Type u_4
inst✝¹ : Countable ι'
m : Measure α
m' : ι' → Measure β
inst✝ : ∀ (n : ι'), SFinite (m' n)
s : Set (α × β)
hs : MeasurableSet s
⊢ ∫⁻ (x : α), (sum m') (Prod.mk x ⁻¹' s) ∂m = ∑' (i : ι'), ∫⁻ (x : α), (m' i) (Prod.mk x ⁻¹' s) ∂m
Module: Mathlib.GroupTheory.Complement

Goal state before:
pp: G : Type u_1
inst✝ : Group G
S T : Set G
hst : IsComplement S T
a : G
ha : a ∈ S
b : G
hb : b ∈ S
hab : a ≠ b
c : G
hc : c ∈ T
d : G
hd : d ∈ T
⊢ (⟨a, ha⟩, ⟨c, hc⟩) ≠ (⟨b, hb⟩, ⟨d, hd⟩)

Tactic:
simp [hab]

Goal state after:
Module: Mathlib.GroupTheory.Complement

Goal state before:
pp: G : Type u_1
inst✝ : Group G
H' H : Subgroup G
h : H' ≤ H
⊢ ∃ S, ↑H' * S = ↑H ∧ Nat.card ↥H' * Nat.card ↑S = Nat.card ↥H

Tactic:
let H'' : Subgroup H := H'.comap H.subtype
  have : H' = H''.map H.subtype := by simp [H'', h]
  rw [this]
  obtain ⟨S, cmem, -⟩ := H''.exists_isComplement_right 1
  refine ⟨H.subtype '' S, ?_, ?_⟩
  · have : H.subtype '' (H'' * S) = H''.map H.subtype * H.subtype '' S := image_mul H.subtype
    rw [← this, cmem.mul_eq]
    simp
  · have : Nat.card H'' * Nat.card S = Nat.card H := cmem.card_mul_card
    rw [← this]
    refine congr_arg₂ (· * ·) ?_ ?_ <;>
      exact Nat.card_congr (Equiv.Set.image _ _ <| subtype_injective H).symm

Goal state after:
Module: Mathlib.MeasureTheory.Constructions.Polish.Basic

Goal state before:
pp: case h₂
γ : Type u_3
β : Type u_4
inst✝⁵ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : OpensMeasurableSpace β
f : γ → β
f_cont : Continuous[inst✝⁵, inst✝³] f
f_inj : Injective f
this✝ : UpgradedIsCompletelyMetrizableSpace γ := upgradeIsCompletelyMetrizable γ
b : Set (Set γ)
b_count : b.Countable
b_nonempty : ∅ ∉ b
hb : IsTopologicalBasis b
this : Encodable ↑b
A : Type (max 0 u_3) := { p // Disjoint ↑p.1 ↑p.2 }
q : A → Set β
hq1 : ∀ (p : A), f '' ↑(↑p).1 ⊆ q p
hq2 : ∀ (p : A), Disjoint (f '' ↑(↑p).2) (q p)
q_meas : ∀ (p : A), MeasurableSet (q p)
E : ↑b → Set β := fun s ↦ closure[inst✝³] (f '' ↑s) ∩ ⋂ t, ⋂ (ht : Disjoint ↑s ↑t), q ⟨(s, t), ht⟩ \ q ⟨(t, s), ⋯⟩
u : ℕ → ℝ
u_anti : StrictAnti u
u_pos : ∀ (n : ℕ), 0 < u n
u_lim : Tendsto u atTop (𝓝 0)
F : ℕ → Set β := fun n ↦ ⋃ s, ⋃ (_ : Bornology.IsBounded ↑s ∧ diam ↑s ≤ u n), E s
x : β
hx : x ∈ ⋂ n, F n
s : ℕ → ↑b
hs : ∀ (n : ℕ), Bornology.IsBounded ↑(s n) ∧ diam ↑(s n) ≤ u n
hxs : ∀ (n : ℕ), x ∈ E (s n)
y : ℕ → γ
hy : ∀ (n : ℕ), y n ∈ ↑(s n)
I : ∀ (m n : ℕ), (↑(s m) ∩ ↑(s n)).Nonempty
⊢ x ∈ range f

Tactic:
have cauchy_y : CauchySeq y := by
      have : Tendsto (fun n => 2 * u n) atTop (𝓝 0) := by
        simpa only [mul_zero] using u_lim.const_mul 2
      refine cauchySeq_of_le_tendsto_0' (fun n => 2 * u n) (fun m n hmn => ?_) this
      rcases I m n with ⟨z, zsm, zsn⟩
      calc
        dist (y m) (y n) ≤ dist (y m) z + dist z (y n) := dist_triangle _ _ _
        _ ≤ u m + u n :=
          (add_le_add ((dist_le_diam_of_mem (hs m).1 (hy m) zsm).trans (hs m).2)
            ((dist_le_diam_of_mem (hs n).1 zsn (hy n)).trans (hs n).2))
        _ ≤ 2 * u m := by linarith [u_anti.antitone hmn]

Goal state after:
case h₂
γ : Type u_3
β : Type u_4
inst✝⁵ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : OpensMeasurableSpace β
f : γ → β
f_cont : Continuous[inst✝⁵, inst✝³] f
f_inj : Injective f
this✝ : UpgradedIsCompletelyMetrizableSpace γ := upgradeIsCompletelyMetrizable γ
b : Set (Set γ)
b_count : b.Countable
b_nonempty : ∅ ∉ b
hb : IsTopologicalBasis b
this : Encodable ↑b
A : Type (max 0 u_3) := { p // Disjoint ↑p.1 ↑p.2 }
q : A → Set β
hq1 : ∀ (p : A), f '' ↑(↑p).1 ⊆ q p
hq2 : ∀ (p : A), Disjoint (f '' ↑(↑p).2) (q p)
q_meas : ∀ (p : A), MeasurableSet (q p)
E : ↑b → Set β := fun s ↦ closure[inst✝³] (f '' ↑s) ∩ ⋂ t, ⋂ (ht : Disjoint ↑s ↑t), q ⟨(s, t), ht⟩ \ q ⟨(t, s), ⋯⟩
u : ℕ → ℝ
u_anti : StrictAnti u
u_pos : ∀ (n : ℕ), 0 < u n
u_lim : Tendsto u atTop (𝓝 0)
F : ℕ → Set β := fun n ↦ ⋃ s, ⋃ (_ : Bornology.IsBounded ↑s ∧ diam ↑s ≤ u n), E s
x : β
hx : x ∈ ⋂ n, F n
s : ℕ → ↑b
hs : ∀ (n : ℕ), Bornology.IsBounded ↑(s n) ∧ diam ↑(s n) ≤ u n
hxs : ∀ (n : ℕ), x ∈ E (s n)
y : ℕ → γ
hy : ∀ (n : ℕ), y n ∈ ↑(s n)
I : ∀ (m n : ℕ), (↑(s m) ∩ ↑(s n)).Nonempty
cauchy_y : CauchySeq y
⊢ x ∈ range f
Module: Mathlib.MeasureTheory.Group.Action

Goal state before:
pp: G : Type u
α : Type w
m : MeasurableSpace α
inst✝² : Group G
inst✝¹ : MulAction G α
μ : Measure α
inst✝ : SMulInvariantMeasure G α μ
c : G
s t : Set α
⊢ μ (c⁻¹ • s ∩ t) = μ (s ∩ c • t)

Tactic:
by
  simpa [inv_inv] using (measure_inter_inv_smul _ c⁻¹ _ _).symm

Goal state after:
Module: Mathlib.MeasureTheory.Group.Action

Goal state before:
pp: G : Type u
α : Type w
m : MeasurableSpace α
inst✝² : Group G
inst✝¹ : MulAction G α
μ : Measure α
inst✝ : SMulInvariantMeasure G α μ
c : G
s t : Set α
⊢ μ (s \ c⁻¹ • t) = μ (c • s \ t)

Tactic:
rw [← measure_smul _ c, smul_set_sdiff, smul_smul, mul_inv_cancel, one_smul]

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

Goal state before:
pp: α : Type u_1
inst✝ : MeasurableSpace α
p : Set α → Prop
μ : Measure α
s : ℕ → Set α
h : ∀ (n : ℕ), (μ.restrict (s n)).InnerRegularWRT p MeasurableSet
hs : univ ⊆ ⋃ n, s n
hmono : Monotone s
F : Set α
hF : MeasurableSet F
r : ℝ≥0∞
hr : r < ⨆ n, μ (F ∩ s n)
hBU : ⋃ n, F ∩ s n = F
this : μ F = ⨆ n, μ (F ∩ s n)
n : ℕ
hn : r < μ (F ∩ s n)
⊢ ∃ K ⊆ F, p K ∧ r < μ K

Tactic:
← restrict_apply hF

Goal state after:
α : Type u_1
inst✝ : MeasurableSpace α
p : Set α → Prop
μ : Measure α
s : ℕ → Set α
h : ∀ (n : ℕ), (μ.restrict (s n)).InnerRegularWRT p MeasurableSet
hs : univ ⊆ ⋃ n, s n
hmono : Monotone s
F : Set α
hF : MeasurableSet F
r : ℝ≥0∞
hr : r < ⨆ n, μ (F ∩ s n)
hBU : ⋃ n, F ∩ s n = F
this : μ F = ⨆ n, μ (F ∩ s n)
n : ℕ
hn : r < (μ.restrict (s n)) F
⊢ ∃ K ⊆ F, p K ∧ r < μ K
Module: Mathlib.Topology.ContinuousMap.CocompactMap

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝¹ : TopologicalSpace α
inst✝ : TopologicalSpace β
f : α ≃ₜ β
K : Set β
hK : IsCompact K
⊢ IsCompact (⇑f ⁻¹' K)

Tactic:
have := f.toEquiv.image_symm_eq_preimage K

Goal state after:
α : Type u_1
β : Type u_2
inst✝¹ : TopologicalSpace α
inst✝ : TopologicalSpace β
f : α ≃ₜ β
K : Set β
hK : IsCompact K
this : ⇑f.symm '' K = ⇑f.toEquiv ⁻¹' K
⊢ IsCompact (⇑f ⁻¹' K)