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

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
μ ν s : Measure α
f : α → ℝ≥0∞
hf : Measurable f
hadd : μ.singularPart ν + ν.withDensity (μ.rnDeriv ν) = s + ν.withDensity f
this : μ.HaveLebesgueDecomposition ν
hmeas : Measurable (μ.rnDeriv ν)
hadd' : μ = μ.singularPart ν + ν.withDensity (μ.rnDeriv ν)
S : Set α
hS₁ : MeasurableSet S
hS₂ : s S = 0
hS₃ : ν Sᶜ = 0
T : Set α
hT₁ : MeasurableSet T
hT₂ : (μ.singularPart ν) T = 0
hT₃ : ν Tᶜ = 0
hνinter : ν (S ∩ T)ᶜ = 0
A : Set α
hA : MeasurableSet A
hs : s (A ∩ (S ∩ T)) = 0
hsing : (μ.singularPart ν) (A ∩ (S ∩ T)) = 0
⊢ (μ.singularPart ν) (A ∩ (S ∩ T)) + (ν.withDensity (μ.rnDeriv ν)) (A ∩ (S ∩ T)) =
    (ν.withDensity (μ.rnDeriv ν)) (A ∩ (S ∩ T))

Tactic:
hsing,

Goal state after:
α : Type u_1
m : MeasurableSpace α
μ ν s : Measure α
f : α → ℝ≥0∞
hf : Measurable f
hadd : μ.singularPart ν + ν.withDensity (μ.rnDeriv ν) = s + ν.withDensity f
this : μ.HaveLebesgueDecomposition ν
hmeas : Measurable (μ.rnDeriv ν)
hadd' : μ = μ.singularPart ν + ν.withDensity (μ.rnDeriv ν)
S : Set α
hS₁ : MeasurableSet S
hS₂ : s S = 0
hS₃ : ν Sᶜ = 0
T : Set α
hT₁ : MeasurableSet T
hT₂ : (μ.singularPart ν) T = 0
hT₃ : ν Tᶜ = 0
hνinter : ν (S ∩ T)ᶜ = 0
A : Set α
hA : MeasurableSet A
hs : s (A ∩ (S ∩ T)) = 0
hsing : (μ.singularPart ν) (A ∩ (S ∩ T)) = 0
⊢ 0 + (ν.withDensity (μ.rnDeriv ν)) (A ∩ (S ∩ T)) = (ν.withDensity (μ.rnDeriv ν)) (A ∩ (S ∩ T))
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: case refine_3
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
p q : ℝ≥0
hpq : p < q
s : Set α := {x | ∃ c, Tendsto (fun a ↦ ρ a / μ a) (v.filterAt x) (𝓝 c)}
o : ℕ → Set α := spanningSets (ρ + μ)
u : ℕ → Set α := fun n ↦ s ∩ {x | v.limRatio ρ x < ↑p} ∩ o n
w : ℕ → Set α := fun n ↦ s ∩ {x | ↑q < v.limRatio ρ x} ∩ o n
x : α
hx : x ∈ {x | v.limRatio ρ x < ↑p}
⊢ x ∈ toMeasurable μ sᶜ ∪ ⋃ n, toMeasurable (ρ + μ) (u n)

Tactic:
by_cases h : x ∈ s

Goal state after:
case pos
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
p q : ℝ≥0
hpq : p < q
s : Set α := {x | ∃ c, Tendsto (fun a ↦ ρ a / μ a) (v.filterAt x) (𝓝 c)}
o : ℕ → Set α := spanningSets (ρ + μ)
u : ℕ → Set α := fun n ↦ s ∩ {x | v.limRatio ρ x < ↑p} ∩ o n
w : ℕ → Set α := fun n ↦ s ∩ {x | ↑q < v.limRatio ρ x} ∩ o n
x : α
hx : x ∈ {x | v.limRatio ρ x < ↑p}
h : x ∈ s
⊢ x ∈ toMeasurable μ sᶜ ∪ ⋃ n, toMeasurable (ρ + μ) (u n)

case neg
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
p q : ℝ≥0
hpq : p < q
s : Set α := {x | ∃ c, Tendsto (fun a ↦ ρ a / μ a) (v.filterAt x) (𝓝 c)}
o : ℕ → Set α := spanningSets (ρ + μ)
u : ℕ → Set α := fun n ↦ s ∩ {x | v.limRatio ρ x < ↑p} ∩ o n
w : ℕ → Set α := fun n ↦ s ∩ {x | ↑q < v.limRatio ρ x} ∩ o n
x : α
hx : x ∈ {x | v.limRatio ρ x < ↑p}
h : x ∉ s
⊢ x ∈ toMeasurable μ sᶜ ∪ ⋃ n, toMeasurable (ρ + μ) (u n)
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: case refine_4
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
p q : ℝ≥0
hpq : p < q
s : Set α := {x | ∃ c, Tendsto (fun a ↦ ρ a / μ a) (v.filterAt x) (𝓝 c)}
o : ℕ → Set α := spanningSets (ρ + μ)
u : ℕ → Set α := fun n ↦ s ∩ {x | v.limRatio ρ x < ↑p} ∩ o n
w : ℕ → Set α := fun n ↦ s ∩ {x | ↑q < v.limRatio ρ x} ∩ o n
x : α
hx : x ∈ {x | ↑q < v.limRatio ρ x}
⊢ x ∈ toMeasurable μ sᶜ ∪ ⋃ n, toMeasurable (ρ + μ) (w n)

Tactic:
by_cases h : x ∈ s

Goal state after:
case pos
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
p q : ℝ≥0
hpq : p < q
s : Set α := {x | ∃ c, Tendsto (fun a ↦ ρ a / μ a) (v.filterAt x) (𝓝 c)}
o : ℕ → Set α := spanningSets (ρ + μ)
u : ℕ → Set α := fun n ↦ s ∩ {x | v.limRatio ρ x < ↑p} ∩ o n
w : ℕ → Set α := fun n ↦ s ∩ {x | ↑q < v.limRatio ρ x} ∩ o n
x : α
hx : x ∈ {x | ↑q < v.limRatio ρ x}
h : x ∈ s
⊢ x ∈ toMeasurable μ sᶜ ∪ ⋃ n, toMeasurable (ρ + μ) (w n)

case neg
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
p q : ℝ≥0
hpq : p < q
s : Set α := {x | ∃ c, Tendsto (fun a ↦ ρ a / μ a) (v.filterAt x) (𝓝 c)}
o : ℕ → Set α := spanningSets (ρ + μ)
u : ℕ → Set α := fun n ↦ s ∩ {x | v.limRatio ρ x < ↑p} ∩ o n
w : ℕ → Set α := fun n ↦ s ∩ {x | ↑q < v.limRatio ρ x} ∩ o n
x : α
hx : x ∈ {x | ↑q < v.limRatio ρ x}
h : x ∉ s
⊢ x ∈ toMeasurable μ sᶜ ∪ ⋃ n, toMeasurable (ρ + μ) (w n)
Module: Mathlib.MeasureTheory.Measure.Decomposition.Lebesgue

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
ν : Measure α
inst✝¹ : SigmaFinite ν
μ : Measure α
inst✝ : SFinite μ
hμ : IsFiniteMeasure μ
s : ℕ → Set α := disjointed (spanningSets ν)
hsm : ∀ (n : ℕ), MeasurableSet (s n)
hs : ∀ (n : ℕ), Fact (ν (s n) < ∞)
ξ : ℕ → Measure α := fun n ↦ (μ.restrict (s n)).singularPart (ν.restrict (s n))
⊢ μ.HaveLebesgueDecomposition ν

Tactic:
set f : ℕ → α → ℝ≥0∞ := fun n ↦ (s n).indicator (rnDeriv (.restrict μ (s n)) (.restrict ν (s n)))

Goal state after:
α : Type u_1
m : MeasurableSpace α
ν : Measure α
inst✝¹ : SigmaFinite ν
μ : Measure α
inst✝ : SFinite μ
hμ : IsFiniteMeasure μ
s : ℕ → Set α := disjointed (spanningSets ν)
hsm : ∀ (n : ℕ), MeasurableSet (s n)
hs : ∀ (n : ℕ), Fact (ν (s n) < ∞)
ξ : ℕ → Measure α := fun n ↦ (μ.restrict (s n)).singularPart (ν.restrict (s n))
f : ℕ → α → ℝ≥0∞ := fun n ↦ (s n).indicator ((μ.restrict (s n)).rnDeriv (ν.restrict (s n)))
⊢ μ.HaveLebesgueDecomposition ν
Module: Mathlib.Topology.EMetricSpace.BoundedVariation

Goal state before:
pp: α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
s : Set α
f : α →ᵤ[singleton '' s] E
⊢ SemicontinuousAt (fun x1 x2 ↦ (fun f ↦ eVariationOn f s) x1 > x2) f

Tactic:
apply @lowerSemicontinuous_aux _ _ _ _ (UniformOnFun α E (s.image singleton)) id (𝓝 f) f s _

Goal state after:
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
s : Set α
f : α →ᵤ[singleton '' s] E
⊢ ∀ x ∈ s, Tendsto (fun i ↦ id i x) (𝓝 f) (𝓝 (f x))
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
x : α
x✝ : x ∈ {x | v.limRatioMeas hρ x = ∞}
o : Set α
xo : x ∈ o
o_open : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] o
μo : ρ o < ∞
s : Set α := {x | v.limRatioMeas hρ x = ∞} ∩ o
ρs : ρ s ≠ ∞
A : ∀ (q : ℝ≥0), 1 ≤ q → μ s ≤ (↑q)⁻¹ * ρ s
⊢ Tendsto (fun q ↦ (↑q)⁻¹ * ρ s) atTop (𝓝 (∞⁻¹ * ρ s))

Tactic:
apply ENNReal.Tendsto.mul_const _ (Or.inr ρs)

Goal state after:
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
x : α
x✝ : x ∈ {x | v.limRatioMeas hρ x = ∞}
o : Set α
xo : x ∈ o
o_open : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] o
μo : ρ o < ∞
s : Set α := ⋯
ρs : ρ s ≠ ∞
A : ∀ (q : ℝ≥0), 1 ≤ q → μ s ≤ (↑q)⁻¹ * ρ s
⊢ Tendsto (fun x ↦ (↑x)⁻¹) atTop (𝓝 ∞⁻¹)
Module: Mathlib.Topology.EMetricSpace.VariationOnFromTo

Goal state before:
pp: α : Type u_1
inst✝² : LinearOrder α
E : Type u_3
inst✝¹ : PseudoMetricSpace E
inst✝ : CompleteSpace E
f : α → E
a b : α
hf : BoundedVariationOn f univ
this : TopologicalSpace α := Preorder.topology α
⊢ Function.leftLim (variationOnFromTo f univ a) b = variationOnFromTo f univ a b - dist (f b) (Function.leftLim f b)

Tactic:
have : OrderTopology α := ⟨rfl⟩

Goal state after:
α : Type u_1
inst✝² : LinearOrder α
E : Type u_3
inst✝¹ : PseudoMetricSpace E
inst✝ : CompleteSpace E
f : α → E
a b : α
hf : BoundedVariationOn f univ
this✝ : TopologicalSpace α := Preorder.topology α
this : OrderTopology α
⊢ Function.leftLim (variationOnFromTo f univ a) b = variationOnFromTo f univ a b - dist (f b) (Function.leftLim f b)
Module: Mathlib.Topology.EMetricSpace.VariationOnFromTo

Goal state before:
pp: α : Type u_1
inst✝² : LinearOrder α
E : Type u_3
inst✝¹ : PseudoMetricSpace E
inst✝ : CompleteSpace E
f : α → E
a b : α
hf : BoundedVariationOn f univ
this : TopologicalSpace α := Preorder.topology α
⊢ Function.rightLim (variationOnFromTo f univ a) b = variationOnFromTo f univ a b + dist (f b) (Function.rightLim f b)

Tactic:
have : OrderTopology α := ⟨rfl⟩

Goal state after:
α : Type u_1
inst✝² : LinearOrder α
E : Type u_3
inst✝¹ : PseudoMetricSpace E
inst✝ : CompleteSpace E
f : α → E
a b : α
hf : BoundedVariationOn f univ
this✝ : TopologicalSpace α := Preorder.topology α
this : OrderTopology α
⊢ Function.rightLim (variationOnFromTo f univ a) b = variationOnFromTo f univ a b + dist (f b) (Function.rightLim f b)
Module: Mathlib.Topology.EMetricSpace.VariationOnFromTo

Goal state before:
pp: α : Type u_1
inst✝³ : LinearOrder α
E : Type u_2
inst✝² : PseudoEMetricSpace E
f : α → E
inst✝¹ : TopologicalSpace α
inst✝ : OrderTopology α
hf : BoundedVariationOn f univ
a x : α
hx : ContinuousWithinAt f (Ici x) x
this : variationOnFromTo f univ a = fun y ↦ variationOnFromTo f univ a x + variationOnFromTo f univ x y
⊢ ContinuousWithinAt (fun y ↦ variationOnFromTo f univ a x + variationOnFromTo f univ x y) (Ici x) x

Tactic:
apply continuousWithinAt_const.add

Goal state after:
α : Type u_1
inst✝³ : LinearOrder α
E : Type u_2
inst✝² : PseudoEMetricSpace E
f : α → E
inst✝¹ : TopologicalSpace α
inst✝ : OrderTopology α
hf : BoundedVariationOn f univ
a x : α
hx : ContinuousWithinAt f (Ici x) x
this : variationOnFromTo f univ a = fun y ↦ variationOnFromTo f univ a x + variationOnFromTo f univ x y
⊢ ContinuousWithinAt (variationOnFromTo f univ x) (Ici x) x
Module: Mathlib.Topology.EMetricSpace.VariationOnFromTo

Goal state before:
pp: α : Type u_1
inst✝³ : LinearOrder α
E : Type u_2
inst✝² : PseudoEMetricSpace E
f : α → E
inst✝¹ : TopologicalSpace α
inst✝ : OrderTopology α
hf : BoundedVariationOn f univ
a x : α
hx : ContinuousWithinAt f (Ici x) x
this : variationOnFromTo f univ a = fun y ↦ variationOnFromTo f univ a x + variationOnFromTo f univ x y
⊢ ContinuousWithinAt f (univ ∩ Ici x) x

Tactic:
by simpa using hx

Goal state after:
Module: Mathlib.Topology.EMetricSpace.BoundedVariation

Goal state before:
pp: α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f : α → E
s : Set α
x : α
hx : x ∈ s
u : ℕ → α
hu : Monotone u
us : ∀ (i : ℕ), u i ∈ s
n : ℕ
h : x < u n
exists_N : ∃ N ≤ n, x < u N
N : ℕ := Nat.find exists_N
hN : N ≤ n ∧ x < u N
w : ℕ → α := fun i ↦ if i < N then u i else if i = N then x else u (i - 1)
hw : Monotone w
Npos : N = 0
⊢ ∑ i ∈ Finset.range n, edist (f (w (1 + i + 1))) (f (w (1 + i))) =
    ∑ i ∈ Finset.Ico 1 (n + 1), edist (f (w (i + 1))) (f (w i))

Tactic:
by
        rw [Finset.range_eq_Ico]
        exact Finset.sum_Ico_add (fun i => edist (f (w (i + 1))) (f (w i))) 0 n 1

Goal state after:
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝³ : NormedAddCommGroup E
inst✝² : SecondCountableTopology α
inst✝¹ : BorelSpace α
inst✝ : IsLocallyFiniteMeasure μ
f : α → E
hf : LocallyIntegrable f μ
x : α
hx : Tendsto (fun a ↦ (∫⁻ (y : α) in a, ‖f y - f x‖ₑ ∂μ) / μ a) (v.filterAt x) (𝓝 0)
this : Tendsto (ENNReal.toReal ∘ fun a ↦ (∫⁻ (y : α) in a, ‖f y - f x‖ₑ ∂μ) / μ a) (v.filterAt x) (𝓝 0)
a : Set α
h'a : μ a < ∞
h''a : IntegrableOn f a μ
A : IntegrableOn (fun y ↦ ↑‖f y - f x‖₊) a μ
⊢ (μ a).toReal⁻¹ * (ENNReal.ofReal (∫ (a : α) in a, ↑‖f a - f x‖₊ ∂μ)).toReal =
    (μ.real a)⁻¹ * ∫ (y : α) in a, ‖f y - f x‖ ∂μ

Tactic:
ENNReal.toReal_ofReal (by positivity)

Goal state after:
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝³ : NormedAddCommGroup E
inst✝² : SecondCountableTopology α
inst✝¹ : BorelSpace α
inst✝ : IsLocallyFiniteMeasure μ
f : α → E
hf : LocallyIntegrable f μ
x : α
hx : Tendsto (fun a ↦ (∫⁻ (y : α) in a, ‖f y - f x‖ₑ ∂μ) / μ a) (v.filterAt x) (𝓝 0)
this : Tendsto (ENNReal.toReal ∘ fun a ↦ (∫⁻ (y : α) in a, ‖f y - f x‖ₑ ∂μ) / μ a) (v.filterAt x) (𝓝 0)
a : Set α
h'a : μ a < ∞
h''a : IntegrableOn f a μ
A : IntegrableOn (fun y ↦ ↑‖f y - f x‖₊) a μ
⊢ (μ a).toReal⁻¹ * ∫ (a : α) in a, ↑‖f a - f x‖₊ ∂μ = (μ.real a)⁻¹ * ∫ (y : α) in a, ‖f y - f x‖ ∂μ
Module: Mathlib.Topology.EMetricSpace.BoundedVariation

Goal state before:
pp: α : Type u_1
inst✝³ : LinearOrder α
E : Type u_2
inst✝² : PseudoEMetricSpace E
inst✝¹ : CompleteSpace E
inst✝ : DenselyOrdered α
f : α → E
a : α
hf : BoundedVariationOn f univ
this : TopologicalSpace α := Preorder.topology α
⊢ eVariationOn f (Iic a) = eVariationOn f (Iio a) + edist (f a) (Function.leftLim f a)

Tactic:
have : OrderTopology α := ⟨rfl⟩

Goal state after:
α : Type u_1
inst✝³ : LinearOrder α
E : Type u_2
inst✝² : PseudoEMetricSpace E
inst✝¹ : CompleteSpace E
inst✝ : DenselyOrdered α
f : α → E
a : α
hf : BoundedVariationOn f univ
this✝ : TopologicalSpace α := Preorder.topology α
this : OrderTopology α
⊢ eVariationOn f (Iic a) = eVariationOn f (Iio a) + edist (f a) (Function.leftLim f a)
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.Restrict

Goal state before:
pp: R : Type u_1
S : Type u_2
A : Type u_3
p q : A → Prop
inst✝²³ : Semifield R
inst✝²² : StarRing R
inst✝²¹ : MetricSpace R
inst✝²⁰ : IsTopologicalSemiring R
inst✝¹⁹ : ContinuousStar R
inst✝¹⁸ : Field S
inst✝¹⁷ : StarRing S
inst✝¹⁶ : MetricSpace S
inst✝¹⁵ : IsTopologicalRing S
inst✝¹⁴ : ContinuousStar S
inst✝¹³ : NonUnitalRing A
inst✝¹² : StarRing A
inst✝¹¹ : Module S A
inst✝¹⁰ : IsScalarTower S A A
inst✝⁹ : SMulCommClass S A A
inst✝⁸ : Algebra R S
inst✝⁷ : Module R A
inst✝⁶ : IsScalarTower R S A
inst✝⁵ : StarModule R S
inst✝⁴ : ContinuousSMul R S
inst✝³ : TopologicalSpace A
inst✝² : NonUnitalContinuousFunctionalCalculus S A q
inst✝¹ : IsScalarTower R A A
inst✝ : SMulCommClass R A A
f : C(S, R)
halg : IsClosedEmbedding ⇑(algebraMap R S)
h0 : p 0
h : ∀ (a : A), p a ↔ q a ∧ QuasispectrumRestricts a ⇑f
a : A
ha : p a
⊢ Function.Injective ⇑(nonUnitalStarAlgHom (cfcₙHom ⋯) ⋯)

Tactic:
exact nonUnitalStarAlgHom_injective (cfcₙHom_injective _) _ halg.injective

Goal state after:
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.NonUnital

Goal state before:
pp: R : Type u_1
A : Type u_2
p : A → Prop
inst✝¹¹ : CommSemiring R
inst✝¹⁰ : Nontrivial R
inst✝⁹ : StarRing R
inst✝⁸ : MetricSpace R
inst✝⁷ : IsTopologicalSemiring R
inst✝⁶ : ContinuousStar R
inst✝⁵ : NonUnitalRing A
inst✝⁴ : StarRing A
inst✝³ : TopologicalSpace A
inst✝² : Module R A
inst✝¹ : IsScalarTower R A A
inst✝ : SMulCommClass R A A
instCFCₙ : NonUnitalContinuousFunctionalCalculus R A p
f : R → R
a : A
ha : ¬p a
⊢ cfcₙ f a = 0

Tactic:
by
  rw [cfcₙ_def, dif_neg (not_and_of_not_left _ ha)]

Goal state after:
Module: Mathlib.Topology.Algebra.NonUnitalAlgebra

Goal state before:
pp: R : Type u_1
A : Type u_2
inst✝⁷ : CommSemiring R
inst✝⁶ : NonUnitalSemiring A
inst✝⁵ : Module R A
inst✝⁴ : IsScalarTower R A A
inst✝³ : SMulCommClass R A A
inst✝² : TopologicalSpace A
inst✝¹ : IsSemitopologicalSemiring A
inst✝ : ContinuousConstSMul R A
x : A
s : NonUnitalSubalgebra R A
hs : IsClosed ↑s
hx : x ∈ s
⊢ {x} ⊆ ↑s

Tactic:
by simpa using hx

Goal state after:
Module: Mathlib.Topology.Algebra.NonUnitalStarAlgebra

Goal state before:
pp: R : Type u_1
A : Type u_2
inst✝¹¹ : CommSemiring R
inst✝¹⁰ : StarRing R
inst✝⁹ : NonUnitalSemiring A
inst✝⁸ : StarRing A
inst✝⁷ : Module R A
inst✝⁶ : IsScalarTower R A A
inst✝⁵ : SMulCommClass R A A
inst✝⁴ : StarModule R A
inst✝³ : TopologicalSpace A
inst✝² : IsSemitopologicalSemiring A
inst✝¹ : ContinuousConstSMul R A
inst✝ : ContinuousStar A
x : A
s : NonUnitalStarSubalgebra R A
hs : IsClosed ↑s
hx : x ∈ s
⊢ {x} ⊆ ↑s

Tactic:
by simpa using hx

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Polynomial

Goal state before:
pp: case mpr.refine_2
a b : ℝ
h : a < b
p : ℝ[X]
q : ℝ[X] := p.comp ((b - a) • X + Polynomial.C a)
⊢ ↑(toContinuousMapOnAlgHom I) q =
    ↑(compRightAlgHom ℝ ℝ ↑(iccHomeoI a b h).symm) (↑(toContinuousMapOnAlgHom (Set.Icc a b)) p)

Tactic:
· ext x
      simp [q, mul_comm]

Goal state after:
Module: Mathlib.Topology.ContinuousMap.StoneWeierstrass

Goal state before:
pp: X : Type u_1
inst✝¹ : TopologicalSpace X
inst✝ : CompactSpace X
A : Subalgebra ℝ C(X, ℝ)
f : ↥A
p : C(↑(Set.Icc (-‖f‖) ‖f‖), ℝ)
⊢ p.comp (↑f).attachBound ∈ A.topologicalClosure

Tactic:
by
  -- `p` itself is in the closure of polynomials, by the Weierstrass theorem,
  have mem_closure : p ∈ (polynomialFunctions (Set.Icc (-‖f‖) ‖f‖)).topologicalClosure :=
    continuousMap_mem_polynomialFunctions_closure _ _ p
  -- and so there are polynomials arbitrarily close.
  have frequently_mem_polynomials := mem_closure_iff_frequently.mp mem_closure
  -- To prove `p.comp (attachBound f)` is in the closure of `A`,
  -- we show there are elements of `A` arbitrarily close.
  apply mem_closure_iff_frequently.mpr
  -- To show that, we pull back the polynomials close to `p`,
  refine
    ((compRightContinuousMap ℝ (attachBound (f : C(X, ℝ)))).continuousAt
            p).tendsto.frequently_map
      _ ?_ frequently_mem_polynomials
  -- but need to show that those pullbacks are actually in `A`.
  rintro _ ⟨g, ⟨-, rfl⟩⟩
  simp only [SetLike.mem_coe, AlgHom.coe_toRingHom,
    Polynomial.toContinuousMapOnAlgHom_apply]
  apply polynomial_comp_attachBound_mem

Goal state after:
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.Unique

Goal state before:
pp: X : Type u_1
inst✝⁵ : TopologicalSpace X
A : Type u_2
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : Algebra ℝ A
inst✝¹ : TopologicalSpace A
inst✝ : IsSemitopologicalRing A
φ : C(X, ℝ≥0) →⋆ₐ[ℝ≥0] A
r : ℝ
⊢ φ ((algebraMap ℝ C(X, ℝ)) r).toNNReal - φ (-(algebraMap ℝ C(X, ℝ)) r).toNNReal = (algebraMap ℝ A) r

Tactic:
obtain (hr | hr) := le_total 0 r
    · lift r to ℝ≥0 using hr
      simpa only [ContinuousMap.toNNReal_algebraMap, ContinuousMap.toNNReal_neg_algebraMap,
        map_zero, sub_zero] using! AlgHomClass.commutes φ r
    · rw [← neg_neg r, ← map_neg, neg_neg (-r)]
      rw [← neg_nonneg] at hr
      lift -r to ℝ≥0 using hr with r
      simpa only [map_neg, ContinuousMap.toNNReal_neg_algebraMap, map_zero,
        ContinuousMap.toNNReal_algebraMap, zero_sub, neg_inj] using! AlgHomClass.commutes φ r

Goal state after:
Module: Mathlib.Analysis.Normed.Algebra.Unitization

Goal state before:
pp: 𝕜 : Type u_1
A : Type u_2
inst✝⁵ : NontriviallyNormedField 𝕜
inst✝⁴ : NonUnitalNormedRing A
inst✝³ : NormedSpace 𝕜 A
inst✝² : IsScalarTower 𝕜 A A
inst✝¹ : SMulCommClass 𝕜 A A
inst✝ : RegularNormedAlgebra 𝕜 A
x : Unitization 𝕜 A
a✝ : Nontrivial A
⊢ ‖(algebraMap 𝕜 (A →L[𝕜] A)) x.toProd.1‖ + ‖(mul 𝕜 A) x.toProd.2‖ = ‖x.toProd.1‖ + ‖x.toProd.2‖

Tactic:
by
        rw [norm_algebraMap', (AddMonoidHomClass.isometry_iff_norm (mul 𝕜 A)).mp (isometry_mul 𝕜 A)]

Goal state after:
Module: Mathlib.Topology.ContinuousMap.StoneWeierstrass

Goal state before:
pp: 𝕜 : Type u_1
inst✝² : RCLike 𝕜
s : Set 𝕜
inst✝¹ : Fact (0 ∈ s)
inst✝ : CompactSpace ↑s
h0' : 0 ∈ s
f : C(↑s, 𝕜)₀
⊢ f ∈ _root_.toContinuousMap ⁻¹' ↑(RingHom.ker (ContinuousMap.evalStarAlgHom 𝕜 𝕜 ⟨0, h0'⟩))

Tactic:
simp only [Set.mem_preimage, SetLike.mem_coe, RingHom.mem_ker,
    ContinuousMap.evalStarAlgHom_apply, ContinuousMap.coe_coe]

Goal state after:
𝕜 : Type u_1
inst✝² : RCLike 𝕜
s : Set 𝕜
inst✝¹ : Fact (0 ∈ s)
inst✝ : CompactSpace ↑s
h0' : 0 ∈ s
f : C(↑s, 𝕜)₀
⊢ f ⟨0, h0'⟩ = 0
Module: Mathlib.Topology.Semicontinuity.Hemicontinuity

Goal state before:
pp: α : Type u_3
β : Type u_4
inst✝¹ : TopologicalSpace α
inst✝ : TopologicalSpace β
f : α → Set β
hf : UpperHemicontinuous f
x : α
hx : f x = ∅
⊢ {a | f a = ∅} ∈ 𝓝 x

Tactic:
upperHemicontinuous_iff,

Goal state after:
α : Type u_3
β : Type u_4
inst✝¹ : TopologicalSpace α
inst✝ : TopologicalSpace β
f : α → Set β
x : α
hx : f x = ∅
hf : ∀ (x : α), UpperHemicontinuousAt f x
⊢ {a | f a = ∅} ∈ 𝓝 x
Module: Mathlib.Topology.Semicontinuity.Hemicontinuity

Goal state before:
pp: α : Type u_3
β : Type u_4
inst✝² : TopologicalSpace α
inst✝¹ : TopologicalSpace β
f : α → Set β
x₀ : α
inst✝ : (𝓝 x₀).IsCountablyGenerated
h : ∀ (x : ℕ → α), Tendsto x atTop (𝓝 x₀) → ∀ y₀ ∈ f x₀, ∃ y, (∀ (n : ℕ), y n ∈ f (x n)) ∧ Tendsto y atTop (𝓝 y₀)
⊢ ∀ (u : Set β), IsOpen[inst✝¹] u → (f x₀ ∩ u).Nonempty → ∀ᶠ (x' : α) in 𝓝 x₀, (f x' ∩ u).Nonempty

Tactic:
intro U hU ⟨y₀, hy₀f, hy₀U⟩

Goal state after:
α : Type u_3
β : Type u_4
inst✝² : TopologicalSpace α
inst✝¹ : TopologicalSpace β
f : α → Set β
x₀ : α
inst✝ : (𝓝 x₀).IsCountablyGenerated
h : ∀ (x : ℕ → α), Tendsto x atTop (𝓝 x₀) → ∀ y₀ ∈ f x₀, ∃ y, (∀ (n : ℕ), y n ∈ f (x n)) ∧ Tendsto y atTop (𝓝 y₀)
U : Set β
hU : IsOpen[inst✝¹] U
y₀ : β
hy₀f : y₀ ∈ f x₀
hy₀U : y₀ ∈ U
⊢ ∀ᶠ (x' : α) in 𝓝 x₀, (f x' ∩ U).Nonempty
Module: Mathlib.Topology.UniformSpace.Closeds

Goal state before:
pp: case a
α : Type u_1
U V : SetRel α α
s t : Set α
hst : (s, t).1 ⊆ (U ○ V).preimage (s, t).2
hts : (s, t).2 ⊆ (U ○ V).image (s, t).1
⊢ (s, t) ∈ hausdorffEntourage U ○ hausdorffEntourage V

Tactic:
simp only [mem_comp, mem_hausdorffEntourage] at *

Goal state after:
case a
α : Type u_1
U V : SetRel α α
s t : Set α
hst : s ⊆ (U ○ V).preimage t
hts : t ⊆ (U ○ V).image s
⊢ ∃ b, (s ⊆ U.preimage b ∧ b ⊆ U.image s) ∧ b ⊆ V.preimage t ∧ t ⊆ V.image b
Module: Mathlib.Topology.UniformSpace.Closeds

Goal state before:
pp: case a
α : Type u_1
U V : SetRel α α
s₁ s₃ s₂ : Set α
h₁₂ : s₁ ⊆ U.preimage s₂
h₂₁ : s₂ ⊆ U.image s₁
h₂₃ : s₂ ⊆ V.preimage s₃
h₃₂ : s₃ ⊆ V.image s₂
⊢ s₁ ⊆ U.preimage s₂ ∧ s₃ ⊆ (U ○ V).image s₁

Tactic:
← h₁₂,

Goal state after:
case a
α : Type u_1
U V : SetRel α α
s₁ s₃ s₂ : Set α
h₁₂ : s₁ ⊆ U.preimage s₂
h₂₁ : s₂ ⊆ U.image s₁
h₂₃ : s₂ ⊆ V.preimage s₃
h₃₂ : s₃ ⊆ V.image s₂
⊢ s₁ ⊆ s₁ ∧ s₃ ⊆ (U ○ V).image s₁
Module: Mathlib.Topology.UniformSpace.Closeds

Goal state before:
pp: α : Type u_1
inst✝ : UniformSpace α
s : Set α
hs : TotallyBounded s
U : SetRel α α
hU : U ∈ 𝓤 α
t : Finset α
ht₂ : s ⊆ ⋃ y ∈ ↑t, {x | (x, y) ∈ Prod.swap ⁻¹' U}
x : α
hx : x ∈ ({x | x ∈ t ∧ ∃ y ∈ s, (x, y) ∈ U}, s).2
y : α
hy : y ∈ ↑t
hxy : x ∈ {x | (x, y) ∈ Prod.swap ⁻¹' U}
⊢ x ∈ U.image ({x | x ∈ t ∧ ∃ y ∈ s, (x, y) ∈ U}, s).1

Tactic:
exact ⟨y, ⟨hy, x, hx, hxy⟩, hxy⟩

Goal state after:
Module: Mathlib.Topology.Sets.VietorisTopology

Goal state before:
pp: α : Type u_1
inst✝ : TopologicalSpace α
K : Set α
hK : IsCompact K
s : Set (Set α)
hsK : s ⊆ 𝒫 K
hs : ∀ L ∈ s, IsCompact L
S : Set (Set (Set α))
hS : S ⊆ powerset '' {U | IsOpen[inst✝] U} ∪ (fun V ↦ {s | (s ∩ V).Nonempty}) '' {V | IsOpen[inst✝] V}
hKS : {t | t ⊆ K ∧ ∀ L ∈ s, (t ∩ L).Nonempty} ⊆ ⋃₀ S
u : Set (Set α) := {U | IsOpen[inst✝] U ∧ {s | (s ∩ U).Nonempty} ∈ S}
L : Set α
hL : L ∈ s
hLu : L ⊆ ⋃ i ∈ u, i
T : Set (Set α)
hTS : T ⊆ u
hT : T.Finite
hLT : L ⊆ ⋃ i ∈ T, i
⊢ (fun U ↦ {s | (s ∩ U).Nonempty}) '' T ⊆ S

Tactic:
by grind [image_subset_iff]

Goal state after:
Module: Mathlib.Topology.Sets.VietorisTopology

Goal state before:
pp: case e'_3
α : Type u_1
inst✝ : TopologicalSpace α
⊢ {⊥} = SetLike.coe ⁻¹' {↑⊥}

Tactic:
← image_singleton (f := SetLike.coe),

Goal state after:
case e'_3
α : Type u_1
inst✝ : TopologicalSpace α
⊢ {⊥} = SetLike.coe ⁻¹' SetLike.coe '' {⊥}