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

Goal state before:
pp: ι : Type u_1
inst✝¹ : Fintype ι
inst✝ : Nonempty ι
p : ℝ
hp : 1 ≤ p
r : ℝ
h₁ : 0 < p
this✝ : (ENNReal.ofReal p).toReal = p
eq_norm : ∀ (x : ι → ℝ), ‖toLp (ENNReal.ofReal p) x‖ = (∑ i, |x i| ^ p) ^ (1 / p)
this : Fact (1 ≤ ENNReal.ofReal p)
nm_zero : ‖toLp (ENNReal.ofReal p) 0‖ = 0
eq_zero : ∀ (x : ι → ℝ), ‖toLp (ENNReal.ofReal p) x‖ = 0 ↔ x = 0
nm_neg : ∀ (x : ι → ℝ), ‖toLp (ENNReal.ofReal p) (-x)‖ = ‖toLp (ENNReal.ofReal p) x‖
nm_add : ∀ (x y : ι → ℝ), ‖toLp (ENNReal.ofReal p) (x + y)‖ ≤ ‖toLp (ENNReal.ofReal p) x‖ + ‖toLp (ENNReal.ofReal p) y‖
nm_smul : ∀ (r : ℝ) (x : ι → ℝ), ‖toLp (ENNReal.ofReal p) (r • x)‖ ≤ ‖r‖ * ‖toLp (ENNReal.ofReal p) x‖
⊢ volume {x | (∑ i, |x i| ^ p) ^ (1 / p) ≤ r} =
    ENNReal.ofReal r ^ card ι * ENNReal.ofReal ((2 * Gamma (1 / p + 1)) ^ card ι / Gamma (↑(card ι) / p + 1))

Tactic:
eq_norm,

Goal state after:
ι : Type u_1
inst✝¹ : Fintype ι
inst✝ : Nonempty ι
p : ℝ
hp : 1 ≤ p
r : ℝ
h₁ : 0 < p
this✝ : (ENNReal.ofReal p).toReal = p
eq_norm : ∀ (x : ι → ℝ), ‖toLp (ENNReal.ofReal p) x‖ = (∑ i, |x i| ^ p) ^ (1 / p)
this : Fact (1 ≤ ENNReal.ofReal p)
eq_zero : ∀ (x : ι → ℝ), (∑ i, |x i| ^ p) ^ (1 / p) = 0 ↔ x = 0
nm_zero : (∑ i, |0 i| ^ p) ^ (1 / p) = 0
nm_neg : ∀ (x : ι → ℝ), (∑ i, |(-x) i| ^ p) ^ (1 / p) = (∑ i, |x i| ^ p) ^ (1 / p)
nm_add : ∀ (x y : ι → ℝ), (∑ i, |(x + y) i| ^ p) ^ (1 / p) ≤ (∑ i, |x i| ^ p) ^ (1 / p) + (∑ i, |y i| ^ p) ^ (1 / p)
nm_smul : ∀ (r : ℝ) (x : ι → ℝ), (∑ i, |(r • x) i| ^ p) ^ (1 / p) ≤ ‖r‖ * (∑ i, |x i| ^ p) ^ (1 / p)
⊢ volume {x | (∑ i, |x i| ^ p) ^ (1 / p) ≤ r} =
    ENNReal.ofReal r ^ card ι * ENNReal.ofReal ((2 * Gamma (1 / p + 1)) ^ card ι / Gamma (↑(card ι) / p + 1))
Module: Mathlib.MeasureTheory.Measure.MeasuredSets

Goal state before:
pp: α : Type u_1
mα : MeasurableSpace α
μ : Measure α
inst✝ : IsFiniteMeasure μ
C : Set (Set α)
hC : IsSetRing C
h'C : ∃ D, D.Countable ∧ D ⊆ C ∧ μ (⋃₀ D)ᶜ = 0
h : mα = generateFrom C
s : Set α
hs : MeasurableSet s
ε✝ : ℝ≥0∞
hε : 0 < ε✝
f : ℕ → Set α
f_disj : Pairwise (Function.onFun Disjoint f)
f_meas : ∀ (i : ℕ), MeasurableSet (f i)
hf : ∀ (i : ℕ) (ε : ℝ≥0∞), 0 < ε → ∃ t ∈ C, μ (t ∆ f i) < ε
ε : ℝ≥0∞
εpos : 0 < ε
⊢ ∃ t ∈ C, μ (t ∆ ⋃ i, f i) < ε

Tactic:
rcases ENNReal.exists_pos_sum_of_countable' (ENNReal.half_pos εpos.ne').ne' ℕ with ⟨δ, δpos, hδ⟩

Goal state after:
α : Type u_1
mα : MeasurableSpace α
μ : Measure α
inst✝ : IsFiniteMeasure μ
C : Set (Set α)
hC : IsSetRing C
h'C : ∃ D, D.Countable ∧ D ⊆ C ∧ μ (⋃₀ D)ᶜ = 0
h : mα = generateFrom C
s : Set α
hs : MeasurableSet s
ε✝ : ℝ≥0∞
hε : 0 < ε✝
f : ℕ → Set α
f_disj : Pairwise (Function.onFun Disjoint f)
f_meas : ∀ (i : ℕ), MeasurableSet (f i)
hf : ∀ (i : ℕ) (ε : ℝ≥0∞), 0 < ε → ∃ t ∈ C, μ (t ∆ f i) < ε
ε : ℝ≥0∞
εpos : 0 < ε
δ : ℕ → ℝ≥0∞
δpos : ∀ (i : ℕ), 0 < δ i
hδ : ∑' (i : ℕ), δ i < ε / 2
⊢ ∃ t ∈ C, μ (t ∆ ⋃ i, f i) < ε
Module: Mathlib.MeasureTheory.Measure.MeasuredSets

Goal state before:
pp: α : Type u_1
mα : MeasurableSpace α
μ : Measure α
inst✝ : IsFiniteMeasure μ
C : Set (Set α)
hC : IsSetSemiring C
h'C : ∃ D, D.Countable ∧ D ⊆ C ∧ μ (⋃₀ D)ᶜ = 0
h : mα = generateFrom C
⊢ Dense (SetLike.coe ⁻¹' supClosure C)

Tactic:
rw [EMetric.dense_iff]
  rintro s ε εpos
  rcases exists_measure_symmDiff_lt_of_generateFrom_isSetSemiring hC h'C h s.2 εpos
    with ⟨t, tC, ht⟩
  refine ⟨⟨t, ?_⟩, by simpa [MeasuredSets.edist_def] using! ht, tC⟩
  rw [h]
  exact measurableSet_generateFrom_of_mem_supClosure tC

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

Goal state before:
pp: case inl
X : Type u_1
inst✝ : MeasurableSpace X
f : Set X → ℝ≥0∞
s : Set X
hs : MeasurableSet s
ε : ℝ≥0
hε : 0 < ε
h : preVariationFun f s ≠ ∞
ε' : ℝ≥0 := min ε (preVariationFun f s).toNNReal
hε' : ↑ε' ≤ preVariationFun f s
this : ε' ≤ ε
hw : preVariationFun f s ≠ 0
⊢ ∃ P, preVariationFun f s ≤ ∑ p ∈ P.parts, f ↑p + ↑ε

Tactic:
have : 0 < ε' := by
      simp only [lt_inf_iff, ε']
      exact ⟨hε, toNNReal_pos hw h⟩
    let a := preVariationFun f s - ε'
    have ha : a < preVariationFun f s := ENNReal.sub_lt_self h hw (by positivity)
    obtain ⟨P, hP⟩ := exists_Finpartition_sum_gt f hs ha
    use P
    calc preVariationFun f s
      _ = a + ε' := (tsub_add_cancel_of_le hε').symm
      _ ≤ ∑ p ∈ P.parts, f p + ε' := by
        exact (ENNReal.add_le_add_iff_right coe_ne_top).mpr (le_of_lt hP)
      _ ≤ ∑ p ∈ P.parts, f p + ε := by gcongr

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

Goal state before:
pp: κ : Type u_2
Z : Type u_3
Y : κ → Type u_6
mY : (j : κ) → MeasurableSpace (Y j)
inst✝⁸ : (j : κ) → TopologicalSpace (Y j)
inst✝⁷ : ∀ (j : κ), BorelSpace (Y j)
inst✝⁶ : ∀ (j : κ), HasOuterApproxClosed (Y j)
mZ : MeasurableSpace Z
inst✝⁵ : TopologicalSpace Z
inst✝⁴ : BorelSpace Z
inst✝³ : HasOuterApproxClosed Z
inst✝² : Fintype κ
μ ν : Measure (Z × ((j : κ) → Y j))
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteMeasure ν
h :
  ∀ (f : Z →ᵇ ℝ) (g : (j : κ) → Y j →ᵇ ℝ),
    ∫ (p : Z × ((j : κ) → Y j)), f p.1 * ∏ j, (g j) (p.2 j) ∂μ =
      ∫ (p : Z × ((j : κ) → Y j)), f p.1 * ∏ j, (g j) (p.2 j) ∂ν
e : Z × ((i : κ) → Y i) ≃ᵐ ((i : κ) → Y i) × Z := MeasurableEquiv.prodComm
⊢ Measure.map (⇑e) μ = Measure.map (⇑e) ν

Tactic:
refine ext_of_integral_prod_mul_boundedContinuousFunction fun f g ↦ ?_

Goal state after:
κ : Type u_2
Z : Type u_3
Y : κ → Type u_6
mY : (j : κ) → MeasurableSpace (Y j)
inst✝⁸ : (j : κ) → TopologicalSpace (Y j)
inst✝⁷ : ∀ (j : κ), BorelSpace (Y j)
inst✝⁶ : ∀ (j : κ), HasOuterApproxClosed (Y j)
mZ : MeasurableSpace Z
inst✝⁵ : TopologicalSpace Z
inst✝⁴ : BorelSpace Z
inst✝³ : HasOuterApproxClosed Z
inst✝² : Fintype κ
μ ν : Measure (Z × ((j : κ) → Y j))
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteMeasure ν
h :
  ∀ (f : Z →ᵇ ℝ) (g : (j : κ) → Y j →ᵇ ℝ),
    ∫ (p : Z × ((j : κ) → Y j)), f p.1 * ∏ j, (g j) (p.2 j) ∂μ =
      ∫ (p : Z × ((j : κ) → Y j)), f p.1 * ∏ j, (g j) (p.2 j) ∂ν
e : Z × ((i : κ) → Y i) ≃ᵐ ((i : κ) → Y i) × Z := MeasurableEquiv.prodComm
f : (i : κ) → Y i →ᵇ ℝ
g : Z →ᵇ ℝ
⊢ ∫ (p : ((i : κ) → Y i) × Z), (∏ i, (f i) (p.1 i)) * g p.2 ∂Measure.map (⇑e) μ =
    ∫ (p : ((i : κ) → Y i) × Z), (∏ i, (f i) (p.1 i)) * g p.2 ∂Measure.map (⇑e) ν
Module: Mathlib.MeasureTheory.Measure.HasOuterApproxClosedProd

Goal state before:
pp: ι : Type u_1
T : Type u_4
X : ι → Type u_5
mX : (i : ι) → MeasurableSpace (X i)
inst✝⁸ : (i : ι) → TopologicalSpace (X i)
inst✝⁷ : ∀ (i : ι), BorelSpace (X i)
inst✝⁶ : ∀ (i : ι), HasOuterApproxClosed (X i)
mT : MeasurableSpace T
inst✝⁵ : TopologicalSpace T
inst✝⁴ : BorelSpace T
inst✝³ : HasOuterApproxClosed T
inst✝² : Finite ι
μ ν : Measure (((i : ι) → X i) × T)
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteMeasure ν
h :
  ∀ (f : ((i : ι) → X i) →ᵇ ℝ) (g : T →ᵇ ℝ),
    ∫ (p : ((i : ι) → X i) × T), f p.1 * g p.2 ∂μ = ∫ (p : ((i : ι) → X i) × T), f p.1 * g p.2 ∂ν
this : Fintype ι
⊢ μ = ν

Tactic:
refine ext_of_integral_prod_mul_boundedContinuousFunction fun f g ↦ ?_

Goal state after:
ι : Type u_1
T : Type u_4
X : ι → Type u_5
mX : (i : ι) → MeasurableSpace (X i)
inst✝⁸ : (i : ι) → TopologicalSpace (X i)
inst✝⁷ : ∀ (i : ι), BorelSpace (X i)
inst✝⁶ : ∀ (i : ι), HasOuterApproxClosed (X i)
mT : MeasurableSpace T
inst✝⁵ : TopologicalSpace T
inst✝⁴ : BorelSpace T
inst✝³ : HasOuterApproxClosed T
inst✝² : Finite ι
μ ν : Measure (((i : ι) → X i) × T)
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteMeasure ν
h :
  ∀ (f : ((i : ι) → X i) →ᵇ ℝ) (g : T →ᵇ ℝ),
    ∫ (p : ((i : ι) → X i) × T), f p.1 * g p.2 ∂μ = ∫ (p : ((i : ι) → X i) × T), f p.1 * g p.2 ∂ν
this : Fintype ι
f : (i : ι) → X i →ᵇ ℝ
g : T →ᵇ ℝ
⊢ ∫ (p : ((i : ι) → X i) × T), (∏ i, (f i) (p.1 i)) * g p.2 ∂μ =
    ∫ (p : ((i : ι) → X i) × T), (∏ i, (f i) (p.1 i)) * g p.2 ∂ν
Module: Mathlib.MeasureTheory.Measure.Support

Goal state before:
pp: X : Type u_1
inst✝² : TopologicalSpace X
inst✝¹ : MeasurableSpace X
μ : Measure X
inst✝ : OpensMeasurableSpace X
s : Set X
x : X
⊢ x ∈ (μ.restrict s).support ↔ ∃ᶠ (u : Set X) in (𝓝[s] x).smallSets, 0 < μ u

Tactic:
rw [nhds_basis_opens x |>.mem_measureSupport,
    (nhdsWithin_basis_open x s).frequently_smallSets pos_mono]
  grind [IsOpen.measurableSet, restrict_apply]

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

Goal state before:
pp: 𝕜 : Type u_2
inst✝⁴ : RCLike 𝕜
E : Type u_3
inst✝³ : MeasurableSpace E
inst✝² : TopologicalSpace E
inst✝¹ : PolishSpace E
inst✝ : BorelSpace E
ι : Type u_4
𝓕 : Filter ι
μ : ι → ProbabilityMeasure E
h_tight : IsTightMeasureSet {x | ∃ n, ↑(μ n) = x}
μ₀ : ProbabilityMeasure E
A : StarSubalgebra 𝕜 (E →ᵇ 𝕜)
hA : (StarSubalgebra.map (toContinuousMapStarₐ 𝕜) A).SeparatesPoints
hμ : ∀ g ∈ A, Tendsto (fun n ↦ ∫ (x : E), g x ∂↑(μ n)) 𝓕 (𝓝 (∫ (x : E), g x ∂↑μ₀))
this✝ : TopologicalSpace.UpgradedIsCompletelyMetrizableSpace E := TopologicalSpace.upgradeIsCompletelyMetrizable E
h✝ : 𝓕.NeBot
U : Ultrafilter ι
hU : ↑U ≤ 𝓕
h_compact : IsCompact (closure[instTopologicalSpace] {x | ∃ n, μ n = x})
μ' : ProbabilityMeasure E
hμ' : Tendsto μ (↑U) (𝓝 μ')
this : ↑μ' = ↑μ₀
⊢ Tendsto μ (↑U) (𝓝 μ₀)

Tactic:
convert! hμ'

Goal state after:
𝕜 : Type u_2
inst✝⁴ : RCLike 𝕜
E : Type u_3
inst✝³ : MeasurableSpace E
inst✝² : TopologicalSpace E
inst✝¹ : PolishSpace E
inst✝ : BorelSpace E
ι : Type u_4
𝓕 : Filter ι
μ : ι → ProbabilityMeasure E
h_tight : IsTightMeasureSet {x | ∃ n, ↑(μ n) = x}
μ₀ : ProbabilityMeasure E
A : StarSubalgebra 𝕜 (E →ᵇ 𝕜)
hA : (StarSubalgebra.map (toContinuousMapStarₐ 𝕜) A).SeparatesPoints
hμ : ∀ g ∈ A, Tendsto (fun n ↦ ∫ (x : E), g x ∂↑(μ n)) 𝓕 (𝓝 (∫ (x : E), g x ∂↑μ₀))
this✝ : TopologicalSpace.UpgradedIsCompletelyMetrizableSpace E := TopologicalSpace.upgradeIsCompletelyMetrizable E
h✝ : 𝓕.NeBot
U : Ultrafilter ι
hU : ↑U ≤ 𝓕
h_compact : IsCompact (closure[instTopologicalSpace] {x | ∃ n, μ n = x})
μ' : ProbabilityMeasure E
hμ' : Tendsto μ (↑U) (𝓝 μ')
this : ↑μ' = ↑μ₀
⊢ μ₀ = μ'
Module: Mathlib.MeasureTheory.Measure.LevyConvergence

Goal state before:
pp: E : Type u_1
inst✝³ : NormedAddCommGroup E
inst✝² : InnerProductSpace ℝ E
inst✝¹ : MeasurableSpace E
inst✝ : BorelSpace E
ι : Type u_2
𝓕 : Filter ι
μ₀ : ProbabilityMeasure E
μ✝ : ι → ProbabilityMeasure E
h : ∀ (t : E), Tendsto (fun n ↦ charFun (↑(μ✝ n)) t) 𝓕 (𝓝 (charFun (↑μ₀) t))
g : E →ᵇ ℂ
w : AddMonoidAlgebra ℂ E
hw : ⇑g = fun x ↦ w.coeff.sum fun a z ↦ z * ↑(probChar (((innerₗ E) x) a))
μ : Measure E
hμ : IsProbabilityMeasure μ
⊢ ∫ (x : E), ∑ x_1 ∈ w.coeff.support, w.coeff x_1 * ↑(probChar (((innerₗ E) x) x_1)) ∂μ =
    ∑ x ∈ w.coeff.support, w.coeff x * ∫ (x_1 : E), ↑(probChar (((innerₗ E) x_1) x)) ∂μ

Tactic:
integral_finsetSum

Goal state after:
E : Type u_1
inst✝³ : NormedAddCommGroup E
inst✝² : InnerProductSpace ℝ E
inst✝¹ : MeasurableSpace E
inst✝ : BorelSpace E
ι : Type u_2
𝓕 : Filter ι
μ₀ : ProbabilityMeasure E
μ✝ : ι → ProbabilityMeasure E
h : ∀ (t : E), Tendsto (fun n ↦ charFun (↑(μ✝ n)) t) 𝓕 (𝓝 (charFun (↑μ₀) t))
g : E →ᵇ ℂ
w : AddMonoidAlgebra ℂ E
hw : ⇑g = fun x ↦ w.coeff.sum fun a z ↦ z * ↑(probChar (((innerₗ E) x) a))
μ : Measure E
hμ : IsProbabilityMeasure μ
⊢ ∑ i ∈ w.coeff.support, ∫ (a : E), w.coeff i * ↑(probChar (((innerₗ E) a) i)) ∂μ =
    ∑ x ∈ w.coeff.support, w.coeff x * ∫ (x_1 : E), ↑(probChar (((innerₗ E) x_1) x)) ∂μ

case hf
E : Type u_1
inst✝³ : NormedAddCommGroup E
inst✝² : InnerProductSpace ℝ E
inst✝¹ : MeasurableSpace E
inst✝ : BorelSpace E
ι : Type u_2
𝓕 : Filter ι
μ₀ : ProbabilityMeasure E
μ✝ : ι → ProbabilityMeasure E
h : ∀ (t : E), Tendsto (fun n ↦ charFun (↑(μ✝ n)) t) 𝓕 (𝓝 (charFun (↑μ₀) t))
g : E →ᵇ ℂ
w : AddMonoidAlgebra ℂ E
hw : ⇑g = fun x ↦ w.coeff.sum fun a z ↦ z * ↑(probChar (((innerₗ E) x) a))
μ : Measure E
hμ : IsProbabilityMeasure μ
⊢ ∀ i ∈ w.coeff.support, Integrable (fun x ↦ w.coeff i * ↑(probChar (((innerₗ E) x) i))) μ
Module: Mathlib.MeasureTheory.Measure.SeparableMeasure

Goal state before:
pp: X : Type u_1
m : MeasurableSpace X
μ : Measure X
𝒜 : Set (Set X)
inst✝ : IsFiniteMeasure μ
h𝒜 : IsSetAlgebra 𝒜
hgen : m = MeasurableSpace.generateFrom 𝒜
s : Set X
f : ℕ → Set X
hs✝ : ∀ (n : ℕ), MeasurableSet (f n)
hf : ∀ (n : ℕ), MeasurableSet (f n) ∧ ∀ (ε : ℝ), 0 < ε → ∃ t ∈ 𝒜, μ.real (f n ∆ t) < ε
ε : ℝ
ε_pos : 0 < ε
this : Filter.Tendsto (fun n ↦ (μ (accumulate f n)).toReal) Filter.atTop (nhds (μ (⋃ i, f i)).toReal)
N : ℕ
hN : ∀ n ≥ N, dist (μ (accumulate f n)).toReal (μ (⋃ i, f i)).toReal < ε / 2
g : ℕ → Set X
g_mem : ∀ (n : ℕ), g n ∈ 𝒜
hg : ∀ (n : ℕ), μ.real (f n ∆ g n) < ε / (2 * (↑N + 1))
⊢ μ.real (⋃ n ∈ Finset.range (N + 1), f n ∆ g n) ≤ ∑ n ∈ Finset.range (N + 1), μ.real (f n ∆ g n)

Tactic:
simp_rw [measureReal_def, ← toReal_sum (fun _ _ ↦ measure_ne_top _ _)]

Goal state after:
X : Type u_1
m : MeasurableSpace X
μ : Measure X
𝒜 : Set (Set X)
inst✝ : IsFiniteMeasure μ
h𝒜 : IsSetAlgebra 𝒜
hgen : m = MeasurableSpace.generateFrom 𝒜
s : Set X
f : ℕ → Set X
hs✝ : ∀ (n : ℕ), MeasurableSet (f n)
hf : ∀ (n : ℕ), MeasurableSet (f n) ∧ ∀ (ε : ℝ), 0 < ε → ∃ t ∈ 𝒜, μ.real (f n ∆ t) < ε
ε : ℝ
ε_pos : 0 < ε
this : Filter.Tendsto (fun n ↦ (μ (accumulate f n)).toReal) Filter.atTop (nhds (μ (⋃ i, f i)).toReal)
N : ℕ
hN : ∀ n ≥ N, dist (μ (accumulate f n)).toReal (μ (⋃ i, f i)).toReal < ε / 2
g : ℕ → Set X
g_mem : ∀ (n : ℕ), g n ∈ 𝒜
hg : ∀ (n : ℕ), μ.real (f n ∆ g n) < ε / (2 * (↑N + 1))
⊢ (μ (⋃ n ∈ Finset.range (N + 1), f n ∆ g n)).toReal ≤ (∑ a ∈ Finset.range (N + 1), μ (f a ∆ g a)).toReal
Module: Mathlib.MeasureTheory.Measure.SeparableMeasure

Goal state before:
pp: X : Type u_1
m : MeasurableSpace X
μ : Measure X
𝒜 : Set (Set X)
h𝒜 : IsSetAlgebra 𝒜
S : μ.FiniteSpanningSetsIn 𝒜
hgen : m = MeasurableSpace.generateFrom 𝒜
s : Set X
ms : MeasurableSet s
hμs : μ s ≠ ∞
ε : ℝ
ε_pos : 0 < ε
T : ℕ → Set X := accumulate S.set
T_mem : ∀ (n : ℕ), T n ∈ 𝒜
T_finite : ∀ (n : ℕ), μ (T n) < ∞
T_spanning : ⋃ n, T n = univ
mono : Monotone fun n ↦ T n ∩ s
this✝ : Filter.Tendsto (fun n ↦ ((⇑μ ∘ fun n ↦ T n ∩ s) n).toReal) Filter.atTop (nhds (μ (⋃ n, T n ∩ s)).toReal)
N : ℕ
hN : ∀ n ≥ N, dist ((⇑μ ∘ fun n ↦ T n ∩ s) n).toReal (μ (⋃ n, T n ∩ s)).toReal < ε / 2
this : Fact (μ (T N) < ∞)
t : Set X
t_mem : t ∈ 𝒜
ht : (μ.restrict (T N)) (s ∆ t) < ENNReal.ofReal (ε / 2)
⊢ ENNReal.ofReal (ε / 2) + ENNReal.ofReal (ε / 2) = ENNReal.ofReal ε

Tactic:
← ofReal_add (by linarith [ε_pos]) (by linarith [ε_pos]),

Goal state after:
X : Type u_1
m : MeasurableSpace X
μ : Measure X
𝒜 : Set (Set X)
h𝒜 : IsSetAlgebra 𝒜
S : μ.FiniteSpanningSetsIn 𝒜
hgen : m = MeasurableSpace.generateFrom 𝒜
s : Set X
ms : MeasurableSet s
hμs : μ s ≠ ∞
ε : ℝ
ε_pos : 0 < ε
T : ℕ → Set X := accumulate S.set
T_mem : ∀ (n : ℕ), T n ∈ 𝒜
T_finite : ∀ (n : ℕ), μ (T n) < ∞
T_spanning : ⋃ n, T n = univ
mono : Monotone fun n ↦ T n ∩ s
this✝ : Filter.Tendsto (fun n ↦ ((⇑μ ∘ fun n ↦ T n ∩ s) n).toReal) Filter.atTop (nhds (μ (⋃ n, T n ∩ s)).toReal)
N : ℕ
hN : ∀ n ≥ N, dist ((⇑μ ∘ fun n ↦ T n ∩ s) n).toReal (μ (⋃ n, T n ∩ s)).toReal < ε / 2
this : Fact (μ (T N) < ∞)
t : Set X
t_mem : t ∈ 𝒜
ht : (μ.restrict (T N)) (s ∆ t) < ENNReal.ofReal (ε / 2)
⊢ ENNReal.ofReal (ε / 2 + ε / 2) = ENNReal.ofReal ε
Module: Mathlib.MeasureTheory.Measure.Prokhorov

Goal state before:
pp: 𝓧 : Type u_1
m𝓧 : MeasurableSpace 𝓧
inst✝² : PseudoMetricSpace 𝓧
inst✝¹ : OpensMeasurableSpace 𝓧
inst✝ : SecondCountableTopology 𝓧
S : Set (ProbabilityMeasure 𝓧)
U : ℕ → Set 𝓧
O : ∀ (i : ℕ), IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (U i)
Cov : ⋃ i, U i = univ
hcomp : IsCompact (closure[ProbabilityMeasure.instTopologicalSpace] S)
ε : ℝ
hε' : 0 ≤ ε
hε : 0 < ε
hεbound : ε ≤ 1
μ : ℕ → ProbabilityMeasure 𝓧
hμInS : ∀ (k : ℕ), μ k ∈ S
hcontradiction : ∀ (k : ℕ), ↑((μ k) (⋃ i, ⋃ (_ : i ≤ k), U i)) ≤ 1 - ↑(NNReal.mk ε hε')
μlim : ProbabilityMeasure 𝓧
left✝ : μlim ∈ closure[ProbabilityMeasure.instTopologicalSpace] S
sub : ℕ → ℕ
hsubmono : StrictMono sub
hμconverges : Tendsto (μ ∘ sub) atTop (𝓝 μlim)
Measurebound : ∀ (n : ℕ), ↑(μlim (⋃ i, ⋃ (_ : i ≤ n), U i)) ≤ 1 - ε
accumulation : Tendsto (fun a ↦ ↑(μlim (⋃ i, ⋃ (_ : i ≤ a), U i))) atTop (𝓝 ↑1)
exceeds_bound : ∀ᶠ (n : ℕ) in atTop, 1 - ε / 2 ≤ ↑(μlim (⋃ i, ⋃ (_ : i ≤ n), U i))
⊢ False

Tactic:
suffices ∀ᶠ n : ℕ in atTop, False from this.exists.choose_spec

Goal state after:
𝓧 : Type u_1
m𝓧 : MeasurableSpace 𝓧
inst✝² : PseudoMetricSpace 𝓧
inst✝¹ : OpensMeasurableSpace 𝓧
inst✝ : SecondCountableTopology 𝓧
S : Set (ProbabilityMeasure 𝓧)
U : ℕ → Set 𝓧
O : ∀ (i : ℕ), IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (U i)
Cov : ⋃ i, U i = univ
hcomp : IsCompact (closure[ProbabilityMeasure.instTopologicalSpace] S)
ε : ℝ
hε' : 0 ≤ ε
hε : 0 < ε
hεbound : ε ≤ 1
μ : ℕ → ProbabilityMeasure 𝓧
hμInS : ∀ (k : ℕ), μ k ∈ S
hcontradiction : ∀ (k : ℕ), ↑((μ k) (⋃ i, ⋃ (_ : i ≤ k), U i)) ≤ 1 - ↑(NNReal.mk ε hε')
μlim : ProbabilityMeasure 𝓧
left✝ : μlim ∈ closure[ProbabilityMeasure.instTopologicalSpace] S
sub : ℕ → ℕ
hsubmono : StrictMono sub
hμconverges : Tendsto (μ ∘ sub) atTop (𝓝 μlim)
Measurebound : ∀ (n : ℕ), ↑(μlim (⋃ i, ⋃ (_ : i ≤ n), U i)) ≤ 1 - ε
accumulation : Tendsto (fun a ↦ ↑(μlim (⋃ i, ⋃ (_ : i ≤ a), U i))) atTop (𝓝 ↑1)
exceeds_bound : ∀ᶠ (n : ℕ) in atTop, 1 - ε / 2 ≤ ↑(μlim (⋃ i, ⋃ (_ : i ≤ n), U i))
⊢ ∀ᶠ (n : ℕ) in atTop, False
Module: Mathlib.MeasureTheory.VectorMeasure.Variation.Basic

Goal state before:
pp: case a
X : Type u_1
mX : MeasurableSpace X
μ : Measure X
inst✝ : IsFiniteMeasure μ
⊢ variation μ.toSignedMeasure ≤ μ

Tactic:
apply variation_le_of_forall_enorm_le (fun s hs ↦ ?_)
    simp [hs, Measure.real, Real.enorm_eq_ofReal]

Goal state after:
Module: Mathlib.MeasureTheory.VectorMeasure.Variation.Basic

Goal state before:
pp: case a
X : Type u_1
mX : MeasurableSpace X
μ : Measure X
inst✝ : IsFiniteMeasure μ
⊢ variation μ.toSignedMeasure ≤ μ

pp: case a
X : Type u_1
mX : MeasurableSpace X
μ : Measure X
inst✝ : IsFiniteMeasure μ
⊢ μ ≤ variation μ.toSignedMeasure

Tactic:
· apply variation_le_of_forall_enorm_le (fun s hs ↦ ?_)
    simp [hs, Measure.real, Real.enorm_eq_ofReal]

Goal state after:
case a
X : Type u_1
mX : MeasurableSpace X
μ : Measure X
inst✝ : IsFiniteMeasure μ
⊢ μ ≤ variation μ.toSignedMeasure
Module: Mathlib.MeasureTheory.VectorMeasure.Variation.Basic

Goal state before:
pp: X : Type u_1
mX : MeasurableSpace X
μ : SignedMeasure X
s : Set X
hs : MeasurableSet s
a : ℝ≥0∞
ha : a < (variation μ) s
P : Finset (Set X)
Ps : ∀ t ∈ P, t ⊆ s
P_disj : (↑P).PairwiseDisjoint id
P_meas : ∀ t ∈ P, MeasurableSet t
hP : a < ∑ p ∈ P, ‖μ p‖ₑ
⊢ ∃ t ⊆ s, MeasurableSet t ∧ a < 2 * ‖μ t‖ₑ

Tactic:
have I : (∑ p ∈ P.filter (fun p ↦ 0 ≤ μ p), ‖μ p‖ₑ) =
      ‖μ (⋃ p ∈ P.filter (fun p ↦ 0 ≤ μ p), p)‖ₑ := by
    simp only [Real.norm_eq_abs, enorm_eq_nnnorm,
      ← ENNReal.ofNNReal_finsetSum, ENNReal.coe_inj, ← NNReal.coe_inj,
      NNReal.coe_sum, coe_nnnorm, Real.norm_eq_abs]
    have A : ∑ x ∈ P with 0 ≤ μ x, |μ x| = μ (⋃ x ∈ P.filter (fun x ↦ 0 ≤ μ x), x) := calc
      _ = ∑ x ∈ P with 0 ≤ μ x, μ x := by
        apply Finset.sum_congr rfl (fun p hp ↦ ?_)
        simp only [Finset.mem_filter] at hp
        simp [hp]
      _ = μ (⋃ x ∈ P.filter (fun x ↦ 0 ≤ μ x), x) := by
        rw [of_biUnion_finset]
        · apply P_disj.subset (by grind)
        · grind
    rw [A, abs_of_nonneg]
    rw [← A]
    exact Finset.sum_nonneg (fun p hp ↦ by positivity)

Goal state after:
X : Type u_1
mX : MeasurableSpace X
μ : SignedMeasure X
s : Set X
hs : MeasurableSet s
a : ℝ≥0∞
ha : a < (variation μ) s
P : Finset (Set X)
Ps : ∀ t ∈ P, t ⊆ s
P_disj : (↑P).PairwiseDisjoint id
P_meas : ∀ t ∈ P, MeasurableSet t
hP : a < ∑ p ∈ P, ‖μ p‖ₑ
I : ∑ p ∈ P with 0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
⊢ ∃ t ⊆ s, MeasurableSet t ∧ a < 2 * ‖μ t‖ₑ
Module: Mathlib.MeasureTheory.VectorMeasure.Variation.Basic

Goal state before:
pp: case inl.refine_2
X : Type u_1
mX : MeasurableSpace X
μ : SignedMeasure X
s : Set X
hs : MeasurableSet s
a : ℝ≥0∞
ha : a < (variation μ) s
P : Finset (Set X)
Ps : ∀ t ∈ P, t ⊆ s
P_disj : (↑P).PairwiseDisjoint id
P_meas : ∀ t ∈ P, MeasurableSet t
hP : a < ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
I : ∑ p ∈ P with 0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
J : ∑ p ∈ P with ¬0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
h : ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ ≤ ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
⊢ MeasurableSet (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)

pp: case inl.refine_3
X : Type u_1
mX : MeasurableSpace X
μ : SignedMeasure X
s : Set X
hs : MeasurableSet s
a : ℝ≥0∞
ha : a < (variation μ) s
P : Finset (Set X)
Ps : ∀ t ∈ P, t ⊆ s
P_disj : (↑P).PairwiseDisjoint id
P_meas : ∀ t ∈ P, MeasurableSet t
hP : a < ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
I : ∑ p ∈ P with 0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
J : ∑ p ∈ P with ¬0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
h : ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ ≤ ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
⊢ a < ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ

Tactic:
· exact Finset.measurableSet_biUnion _ (by grind)

Goal state after:
case inl.refine_3
X : Type u_1
mX : MeasurableSpace X
μ : SignedMeasure X
s : Set X
hs : MeasurableSet s
a : ℝ≥0∞
ha : a < (variation μ) s
P : Finset (Set X)
Ps : ∀ t ∈ P, t ⊆ s
P_disj : (↑P).PairwiseDisjoint id
P_meas : ∀ t ∈ P, MeasurableSet t
hP : a < ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
I : ∑ p ∈ P with 0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
J : ∑ p ∈ P with ¬0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
h : ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ ≤ ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
⊢ a < ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
Module: Mathlib.MeasureTheory.VectorMeasure.Variation.Basic

Goal state before:
pp: case inr.refine_2
X : Type u_1
mX : MeasurableSpace X
μ : SignedMeasure X
s : Set X
hs : MeasurableSet s
a : ℝ≥0∞
ha : a < (variation μ) s
P : Finset (Set X)
Ps : ∀ t ∈ P, t ⊆ s
P_disj : (↑P).PairwiseDisjoint id
P_meas : ∀ t ∈ P, MeasurableSet t
hP : a < ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
I : ∑ p ∈ P with 0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
J : ∑ p ∈ P with ¬0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
h : ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ ≤ ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
⊢ MeasurableSet (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)

pp: case inr.refine_3
X : Type u_1
mX : MeasurableSpace X
μ : SignedMeasure X
s : Set X
hs : MeasurableSet s
a : ℝ≥0∞
ha : a < (variation μ) s
P : Finset (Set X)
Ps : ∀ t ∈ P, t ⊆ s
P_disj : (↑P).PairwiseDisjoint id
P_meas : ∀ t ∈ P, MeasurableSet t
hP : a < ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
I : ∑ p ∈ P with 0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
J : ∑ p ∈ P with ¬0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
h : ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ ≤ ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
⊢ a < ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ

Tactic:
· exact Finset.measurableSet_biUnion _ (by grind)

Goal state after:
case inr.refine_3
X : Type u_1
mX : MeasurableSpace X
μ : SignedMeasure X
s : Set X
hs : MeasurableSet s
a : ℝ≥0∞
ha : a < (variation μ) s
P : Finset (Set X)
Ps : ∀ t ∈ P, t ⊆ s
P_disj : (↑P).PairwiseDisjoint id
P_meas : ∀ t ∈ P, MeasurableSet t
hP : a < ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
I : ∑ p ∈ P with 0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ
J : ∑ p ∈ P with ¬0 ≤ μ p, ‖μ p‖ₑ = ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
h : ‖μ (⋃ p ∈ {p ∈ P | 0 ≤ μ p}, p)‖ₑ ≤ ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
⊢ a < ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ + ‖μ (⋃ p ∈ {p ∈ P | ¬0 ≤ μ p}, p)‖ₑ
Module: Mathlib.MeasureTheory.VectorMeasure.SetIntegral

Goal state before:
pp: case convert_5
X : Type u_2
E : Type u_3
F : Type u_4
G : Type u_5
mX : MeasurableSpace X
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedAddCommGroup G
μ : VectorMeasure X F
f : X → E
inst✝³ : NormedSpace ℝ E
inst✝² : NormedSpace ℝ F
inst✝¹ : NormedSpace ℝ G
B : E →L[ℝ] F →L[ℝ] G
ι : Type u_7
inst✝ : Fintype ι
s : ι → Set X
hs : ∀ (i : ι), MeasurableSet (s i)
h's : Pairwise (Disjoint on s)
hf : ∀ (i : ι), μ.IntegrableOn f (s i)
⊢ (↑Finset.univ).Pairwise (Disjoint on s)

Tactic:
· simp [pairwise_univ, h's]

Goal state after: