awhecmu/canonical-drafter-extract-mathlib huggingface dataset:
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
neg :
  ∀ (x : α),
    LE.le (α := ℝ≥0) (F.indicator (fun (x : α) ↦ c) x : ℝ≥0)
      ((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x : ℝ≥0)
⊢ ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
          ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
have neg₁ : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
  ∫⁻ (x : α), (↑(F.indicator (fun (x : α) ↦ c) x) : ℝ≥0∞) ∂μ + ε
Tactic: refine
      ⟨Set.indicator F fun _ => c, fun x => ?_, F_closed.upperSemicontinuous_indicator zero_le,
        ?_⟩
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
x : α
⊢ LE.le (α := ℝ≥0) (F.indicator (fun (x : α) ↦ c) x : ℝ≥0)
    ((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x : ℝ≥0)
have neg : LE.le (α := ℝ≥0) (F.indicator (fun (x : α) ↦ c) x) (s.indicator (fun (x : α) ↦ c) x)
Tactic: simp only [SimpleFunc.coe_const, SimpleFunc.const_zero, SimpleFunc.coe_zero,
        Set.piecewise_eq_indicator, SimpleFunc.coe_piecewise, ← Function.const_def]
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
x : α
⊢ LE.le (α := ℝ≥0) (F.indicator (fun (x : α) ↦ c) x) (s.indicator (fun (x : α) ↦ c) x)
have h₁ : 0 ≤ c
Tactic: grw [Fs]
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
x : α
h₁ : 0 ≤ c
⊢ LE.le (α := ℝ≥0) (F.indicator (fun (x : α) ↦ c) x) (s.indicator (fun (x : α) ↦ c) x)
have neg : LE.le (α := ℝ≥0) (s.indicator (fun (x : α) ↦ c) x) (s.indicator (fun (x : α) ↦ c) x)
Tactic: grw [Fs]
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
⊢ ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
    ∫⁻ (x : α), (↑(F.indicator (fun (x : α) ↦ c) x) : ℝ≥0∞) ∂μ + ε
have neg : HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) ≤
  HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) + ε
Tactic: suffices (c : ℝ≥0∞) * μ s ≤ c * μ F + ε by
        simpa only [hs, F_closed.measurableSet, SimpleFunc.coe_const, Function.const_apply,
          lintegral_const, ENNReal.coe_indicator, Set.univ_inter, MeasurableSet.univ,
          SimpleFunc.const_zero, lintegral_indicator, SimpleFunc.coe_zero,
          Set.piecewise_eq_indicator, SimpleFunc.coe_piecewise, Measure.restrict_apply]
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
⊢ HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) ≤
    (↑c : ℝ≥0∞) * HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
have grw : (↑c : ℝ≥0∞) * HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞)) ≤
  (↑c : ℝ≥0∞) * HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
Tactic: grw [μF]
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
⊢ (↑c : ℝ≥0∞) * HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞)) =
    HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) + ε
have simp_rw : HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) + (↑c : ℝ≥0∞) * (ε / (↑c : ℝ≥0∞)) =
  HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) + ε
Tactic: simp_rw [mul_add]
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
⊢ HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) + (↑c : ℝ≥0∞) * (ε / (↑c : ℝ≥0∞)) =
    HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) + ε
have rw : (↑c : ℝ≥0∞) ≠ 0
Tactic: rw [ENNReal.mul_div_cancel _ ENNReal.coe_ne_top]
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
⊢ HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) ≤
    HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) + ε
have μ₁ : HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) ≤
  (↑c : ℝ≥0∞) * HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
Tactic: calc
        (c : ℝ≥0∞) * μ s ≤ c * (μ F + ε / c) := by grw [μF]
        _ = c * μ F + ε := by
          simp_rw [mul_add]
          rw [ENNReal.mul_div_cancel _ ENNReal.coe_ne_top]
          simpa using hc
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : ¬c = 0
μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)
this : 0 < ε / (↑c : ℝ≥0∞)
F : Set α
Fs : F ⊆ s
F_closed : IsClosed F
μF : (μ : (a : Set α) → ℝ≥0∞) s < HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
μ₁ :
  HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) ≤
    (↑c : ℝ≥0∞) * HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞))
⊢ HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) ≤
    HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) + ε
have μ₂ : (↑c : ℝ≥0∞) * HAdd.hAdd (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) (ε / (↑c : ℝ≥0∞)) =
  HMul.hMul (β := ℝ≥0∞) (↑c : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) F : ℝ≥0∞) + ε
Tactic: calc
        (c : ℝ≥0∞) * μ s ≤ c * (μ F + ε / c) := by grw [μF]
        _ = c * μ F + ε := by
          simp_rw [mul_add]
          rw [ENNReal.mul_div_cancel _ ENNReal.coe_ne_top]
          simpa using hc
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
⊢ ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
          ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
have pos : ∀ (hc : c = 0),
  ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
          ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
Tactic: classical
    by_cases hc : c = 0
    · exact ⟨fun _ => 0, by simp [hc, upperSemicontinuous_const]⟩
    have μs_lt_top : μ s < ∞ := by simpa [hs, hc, ENNReal.mul_eq_top, lt_top_iff_ne_top] using int_f
    have : (0 : ℝ≥0∞) < ε / c := ENNReal.div_pos_iff.2 ⟨ε0, ENNReal.coe_ne_top⟩
    obtain ⟨F, Fs, F_closed, μF⟩ : ∃ (F : _), F ⊆ s ∧ IsClosed F ∧ μ s < μ F + ε / c :=
      hs.exists_isClosed_lt_add μs_lt_top.ne this.ne'
    refine
      ⟨Set.indicator F fun _ => c, fun x => ?_, F_closed.upperSemicontinuous_indicator zero_le,
        ?_⟩
    · simp only [SimpleFunc.coe_const, SimpleFunc.const_zero, SimpleFunc.coe_zero,
        Set.piecewise_eq_indicator, SimpleFunc.coe_piecewise, ← Function.const_def]
      grw [Fs]
    · suffices (c : ℝ≥0∞) * μ s ≤ c * μ F + ε by
        simpa only [hs, F_closed.measurableSet, SimpleFunc.coe_const, Function.const_apply,
          lintegral_const, ENNReal.coe_indicator, Set.univ_inter, MeasurableSet.univ,
          SimpleFunc.const_zero, lintegral_indicator, SimpleFunc.coe_zero,
          Set.piecewise_eq_indicator, SimpleFunc.coe_piecewise, Measure.restrict_apply]
      calc
        (c : ℝ≥0∞) * μ s ≤ c * (μ F + ε / c) := by grw [μF]
        _ = c * μ F + ε := by
          simp_rw [mul_add]
          rw [ENNReal.mul_div_cancel _ ENNReal.coe_ne_top]
          simpa using hc
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
pos :
  ∀ (hc : c = 0),
    ∃ (g : α → ℝ≥0),
      (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
        UpperSemicontinuous g ∧
          ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
            ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
⊢ ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
          ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
have neg : ∀ (hc : ¬c = 0),
  ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
          ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
Tactic: classical
    by_cases hc : c = 0
    · exact ⟨fun _ => 0, by simp [hc, upperSemicontinuous_const]⟩
    have μs_lt_top : μ s < ∞ := by simpa [hs, hc, ENNReal.mul_eq_top, lt_top_iff_ne_top] using int_f
    have : (0 : ℝ≥0∞) < ε / c := ENNReal.div_pos_iff.2 ⟨ε0, ENNReal.coe_ne_top⟩
    obtain ⟨F, Fs, F_closed, μF⟩ : ∃ (F : _), F ⊆ s ∧ IsClosed F ∧ μ s < μ F + ε / c :=
      hs.exists_isClosed_lt_add μs_lt_top.ne this.ne'
    refine
      ⟨Set.indicator F fun _ => c, fun x => ?_, F_closed.upperSemicontinuous_indicator zero_le,
        ?_⟩
    · simp only [SimpleFunc.coe_const, SimpleFunc.const_zero, SimpleFunc.coe_zero,
        Set.piecewise_eq_indicator, SimpleFunc.coe_piecewise, ← Function.const_def]
      grw [Fs]
    · suffices (c : ℝ≥0∞) * μ s ≤ c * μ F + ε by
        simpa only [hs, F_closed.measurableSet, SimpleFunc.coe_const, Function.const_apply,
          lintegral_const, ENNReal.coe_indicator, Set.univ_inter, MeasurableSet.univ,
          SimpleFunc.const_zero, lintegral_indicator, SimpleFunc.coe_zero,
          Set.piecewise_eq_indicator, SimpleFunc.coe_piecewise, Measure.restrict_apply]
      calc
        (c : ℝ≥0∞) * μ s ≤ c * (μ F + ε / c) := by grw [μF]
        _ = c * μ F + ε := by
          simp_rw [mul_add]
          rw [ENNReal.mul_div_cancel _ ENNReal.coe_ne_top]
          simpa using hc
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
pos :
  ∀ (hc : c = 0),
    ∃ (g : α → ℝ≥0),
      (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
        UpperSemicontinuous g ∧
          ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
            ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
neg neg₁ :
  ∀ (hc : ¬c = 0),
    ∃ (g : α → ℝ≥0),
      (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
        UpperSemicontinuous g ∧
          ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
            ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
⊢ ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
          ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
have neg₂ : ∀ (hc : ¬c = 0) (μs_lt_top : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) s : ℝ≥0∞) (∞ : ℝ≥0∞)),
  ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((piecewise s hs (const α c) (const α 0) : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤
          ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
Tactic: classical
    by_cases hc : c = 0
    · exact ⟨fun _ => 0, by simp [hc, upperSemicontinuous_const]⟩
    have μs_lt_top : μ s < ∞ := by simpa [hs, hc, ENNReal.mul_eq_top, lt_top_iff_ne_top] using int_f
    have : (0 : ℝ≥0∞) < ε / c := ENNReal.div_pos_iff.2 ⟨ε0, ENNReal.coe_ne_top⟩
    obtain ⟨F, Fs, F_closed, μF⟩ : ∃ (F : _), F ⊆ s ∧ IsClosed F ∧ μ s < μ F + ε / c :=
      hs.exists_isClosed_lt_add μs_lt_top.ne this.ne'
    refine
      ⟨Set.indicator F fun _ => c, fun x => ?_, F_closed.upperSemicontinuous_indicator zero_le,
        ?_⟩
    · simp only [SimpleFunc.coe_const, SimpleFunc.const_zero, SimpleFunc.coe_zero,
        Set.piecewise_eq_indicator, SimpleFunc.coe_piecewise, ← Function.const_def]
      grw [Fs]
    · suffices (c : ℝ≥0∞) * μ s ≤ c * μ F + ε by
        simpa only [hs, F_closed.measurableSet, SimpleFunc.coe_const, Function.const_apply,
          lintegral_const, ENNReal.coe_indicator, Set.univ_inter, MeasurableSet.univ,
          SimpleFunc.const_zero, lintegral_indicator, SimpleFunc.coe_zero,
          Set.piecewise_eq_indicator, SimpleFunc.coe_piecewise, Measure.restrict_apply]
      calc
        (c : ℝ≥0∞) * μ s ≤ c * (μ F + ε / c) := by grw [μF]
        _ = c * μ F + ε := by
          simp_rw [mul_add]
          rw [ENNReal.mul_div_cancel _ ENNReal.coe_ne_top]
          simpa using hc
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
f₁ f₂ : α →ₛ ℝ≥0
h :
  Disjoint (α := Set α) (Function.support (M := ℝ≥0) (⇑f₁ : (a : α) → ℝ≥0))
    (Function.support (M := ℝ≥0) (⇑f₂ : (a : α) → ℝ≥0))
h₁ :
  ∀ (int_f : ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞) {ε : ℝ≥0∞} (ε0 : ε ≠ 0),
    ∃ (g : α → ℝ≥0),
      (∀ (x : α), g x ≤ (f₁ : (a : α) → ℝ≥0) x) ∧
        UpperSemicontinuous g ∧ ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
h₂ :
  ∀ (int_f : ∫⁻ (x : α), (↑((f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞) {ε : ℝ≥0∞} (ε0 : ε ≠ 0),
    ∃ (g : α → ℝ≥0),
      (∀ (x : α), g x ≤ (f₂ : (a : α) → ℝ≥0) x) ∧
        UpperSemicontinuous g ∧ ∫⁻ (x : α), (↑((f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
int_f : ∫⁻ (x : α), (↑((f₁ + f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
⊢ ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ + ∫⁻ (x : α), (↑((f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
have rwa : ∫⁻ (a : α), (↑((f₁ : (a : α) → ℝ≥0) a) : ℝ≥0∞) + (↑((f₂ : (a : α) → ℝ≥0) a) : ℝ≥0∞) ∂μ ≠ ∞
Tactic: rwa [← lintegral_add_left f₁.measurable.coe_nnreal_ennreal]
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (hypothesis)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
f₁ f₂ : α →ₛ ℝ≥0
h :
  Disjoint (α := Set α) (Function.support (M := ℝ≥0) (⇑f₁ : (a : α) → ℝ≥0))
    (Function.support (M := ℝ≥0) (⇑f₂ : (a : α) → ℝ≥0))
h₁ :
  ∀ (int_f : ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞) {ε : ℝ≥0∞} (ε0 : ε ≠ 0),
    ∃ (g : α → ℝ≥0),
      (∀ (x : α), g x ≤ (f₁ : (a : α) → ℝ≥0) x) ∧
        UpperSemicontinuous g ∧ ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
h₂ :
  ∀ (int_f : ∫⁻ (x : α), (↑((f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞) {ε : ℝ≥0∞} (ε0 : ε ≠ 0),
    ∃ (g : α → ℝ≥0),
      (∀ (x : α), g x ≤ (f₂ : (a : α) → ℝ≥0) x) ∧
        UpperSemicontinuous g ∧ ∫⁻ (x : α), (↑((f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
int_f : ∫⁻ (x : α), (↑((f₁ + f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
⊢ ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (f₁ + f₂ : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((f₁ + f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
have A : ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ + ∫⁻ (x : α), (↑((f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
Tactic: have A : ((∫⁻ x : α, f₁ x ∂μ) + ∫⁻ x : α, f₂ x ∂μ) ≠ ⊤ := by
      rwa [← lintegral_add_left f₁.measurable.coe_nnreal_ennreal]
-- Lean 4 proof step from Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory (goal)
Goal:
α : Type u_1
inst : TopologicalSpace α
inst_1 : MeasurableSpace α
inst_2 : BorelSpace α
μ : Measure α
inst_3 : μ.WeaklyRegular
f₁ f₂ : α →ₛ ℝ≥0
h :
  Disjoint (α := Set α) (Function.support (M := ℝ≥0) (⇑f₁ : (a : α) → ℝ≥0))
    (Function.support (M := ℝ≥0) (⇑f₂ : (a : α) → ℝ≥0))
h₁ :
  ∀ (int_f : ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞) {ε : ℝ≥0∞} (ε0 : ε ≠ 0),
    ∃ (g : α → ℝ≥0),
      (∀ (x : α), g x ≤ (f₁ : (a : α) → ℝ≥0) x) ∧
        UpperSemicontinuous g ∧ ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
h₂ :
  ∀ (int_f : ∫⁻ (x : α), (↑((f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞) {ε : ℝ≥0∞} (ε0 : ε ≠ 0),
    ∃ (g : α → ℝ≥0),
      (∀ (x : α), g x ≤ (f₂ : (a : α) → ℝ≥0) x) ∧
        UpperSemicontinuous g ∧ ∫⁻ (x : α), (↑((f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
int_f : ∫⁻ (x : α), (↑((f₁ + f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
A : ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ + ∫⁻ (x : α), (↑((f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≠ ∞
⊢ ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (f₁ + f₂ : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((f₁ + f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
have add : ∀ (g₁ : α → ℝ≥0) (f₁_le_g₁ : ∀ (x : α), g₁ x ≤ (f₁ : (a : α) → ℝ≥0) x) (g₁cont : UpperSemicontinuous g₁)
  (g₁int : ∫⁻ (x : α), (↑((f₁ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g₁ x) : ℝ≥0∞) ∂μ + ε / 2),
  ∃ (g : α → ℝ≥0),
    (∀ (x : α), g x ≤ (f₁ + f₂ : (a : α) → ℝ≥0) x) ∧
      UpperSemicontinuous g ∧
        ∫⁻ (x : α), (↑((f₁ + f₂ : (a : α) → ℝ≥0) x) : ℝ≥0∞) ∂μ ≤ ∫⁻ (x : α), (↑(g x) : ℝ≥0∞) ∂μ + ε
Tactic: rcases h₁ (ENNReal.add_ne_top.1 A).1 (ENNReal.half_pos ε0).ne' with
      ⟨g₁, f₁_le_g₁, g₁cont, g₁int⟩