mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Analysis.Normed.Operator.Extend

Goal state before:
pp: 𝕜 : Type u_1
𝕜₂ : Type u_2
E : Type u_3
Eₗ : Type u_4
F : Type u_5
Fₗ : Type u_6
inst✝¹⁷ : AddCommGroup E
inst✝¹⁶ : UniformSpace E
inst✝¹⁵ : IsUniformAddGroup E
inst✝¹⁴ : AddCommGroup F
inst✝¹³ : UniformSpace F
inst✝¹² : IsUniformAddGroup F
inst✝¹¹ : T0Space F
inst✝¹⁰ : AddCommMonoid Eₗ
inst✝⁹ : UniformSpace Eₗ
inst✝⁸ : ContinuousAdd Eₗ
inst✝⁷ : Semiring 𝕜
inst✝⁶ : Semiring 𝕜₂
inst✝⁵ : Module 𝕜 E
inst✝⁴ : Module 𝕜₂ F
inst✝³ : Module 𝕜 Eₗ
inst✝² : ContinuousConstSMul 𝕜 Eₗ
inst✝¹ : ContinuousConstSMul 𝕜₂ F
σ₁₂ : 𝕜 →+* 𝕜₂
f g : E →SL[σ₁₂] F
inst✝ : CompleteSpace F
e : E →L[𝕜] Eₗ
h : DenseRange ⇑e ∧ IsUniformInducing ⇑e
cont : Continuous (⋯.extend ⇑f)
eq : ∀ (b : E), ⋯.extend (⇑f) (e b) = f b
k : 𝕜
⊢ ∀ (x : Eₗ), ⋯.extend (⇑f) (k • x) = σ₁₂ k • ⋯.extend (⇑f) x

Tactic:
refine fun b => h.1.induction_on b ?_ ?_
      · exact isClosed_eq (cont.comp (continuous_const_smul _))
          ((continuous_const_smul _).comp cont)
      · intro x
        rw [← map_smul]
        simp only [eq]
        exact map_smulₛₗ _ _ _

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.L1

Goal state before:
pp: α : Type u_1
E : Type u_2
inst✝¹ : NormedAddCommGroup E
m : MeasurableSpace α
μ : Measure α
inst✝ : NormedSpace ℝ E
f : ↥(α →₁ₛ[μ] E)
⊢ ‖{ toFun := integral, map_add' := ⋯, map_smul' := ⋯ } f‖ ≤ 1 * ‖f‖

Tactic:
by
    simpa [one_mul] using norm_integral_le_norm f

Goal state after:
Module: Mathlib.MeasureTheory.Integral.FinMeasAdditive

Goal state before:
pp: α : Type u_1
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
m : MeasurableSpace α
μ : Measure α
G'' : Type u_8
inst✝³ : NormedAddCommGroup G''
inst✝² : PartialOrder G''
inst✝¹ : IsOrderedAddMonoid G''
inst✝ : NormedSpace ℝ G''
T T' : Set α → E →L[ℝ] G''
hTT' : ∀ (s : Set α), MeasurableSet s → μ s < ∞ → ∀ (x : E), (T s) x ≤ (T' s) x
f : α →ₛ E
hf : Integrable (⇑f) μ
⊢ setToSimpleFunc T f ≤ setToSimpleFunc T' f

Tactic:
unfold setToSimpleFunc
  gcongr with i _
  by_cases h0 : i = 0
  · simp [h0]
  · exact hTT' _ (measurableSet_fiber _ _) (measure_preimage_lt_top_of_integrable _ hf h0) i

Goal state after:
Module: Mathlib.MeasureTheory.Function.SimpleFuncDenseLp

Goal state before:
pp: case pos
α : Type u_1
E : Type u_4
inst✝¹ : MeasurableSpace α
inst✝ : NormedAddCommGroup E
p : ℝ≥0∞
μ : Measure α
_i : Fact (1 ≤ p)
hp_ne_top : p ≠ ∞
motive : (α → E) → Prop
indicator : ∀ (c : E) ⦃s : Set α⦄, MeasurableSet s → μ s < ∞ → motive (s.indicator fun x ↦ c)
add :
  ∀ ⦃f g : α → E⦄, Disjoint (support f) (support g) → MemLp f p μ → MemLp g p μ → motive f → motive g → motive (f + g)
closed : IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] {f | motive ↑↑f}
ae : ∀ ⦃f g : α → E⦄, f =ᵐ[μ] g → MemLp f p μ → motive f → motive g
c : E
s : Set α
hs : MeasurableSet s
h : MemLp (⇑(SimpleFunc.piecewise s hs (SimpleFunc.const α c) (SimpleFunc.const α 0))) p μ
hc : c = 0
⊢ motive ⇑(SimpleFunc.piecewise s hs (SimpleFunc.const α c) (SimpleFunc.const α 0))

Tactic:
subst hc

Goal state after:
case pos
α : Type u_1
E : Type u_4
inst✝¹ : MeasurableSpace α
inst✝ : NormedAddCommGroup E
p : ℝ≥0∞
μ : Measure α
_i : Fact (1 ≤ p)
hp_ne_top : p ≠ ∞
motive : (α → E) → Prop
indicator : ∀ (c : E) ⦃s : Set α⦄, MeasurableSet s → μ s < ∞ → motive (s.indicator fun x ↦ c)
add :
  ∀ ⦃f g : α → E⦄, Disjoint (support f) (support g) → MemLp f p μ → MemLp g p μ → motive f → motive g → motive (f + g)
closed : IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] {f | motive ↑↑f}
ae : ∀ ⦃f g : α → E⦄, f =ᵐ[μ] g → MemLp f p μ → motive f → motive g
s : Set α
hs : MeasurableSet s
h : MemLp (⇑(SimpleFunc.piecewise s hs (SimpleFunc.const α 0) (SimpleFunc.const α 0))) p μ
⊢ motive ⇑(SimpleFunc.piecewise s hs (SimpleFunc.const α 0) (SimpleFunc.const α 0))
Module: Mathlib.MeasureTheory.Integral.Bochner.Basic

Goal state before:
pp: case neg
α : Type u_1
m : MeasurableSpace α
μ : Measure α
f : α → ℝ
hf : 0 ≤ᵐ[μ] f
hfm : AEStronglyMeasurable f μ
hfi : ¬Integrable f μ
⊢ ∫ (a : α), f a ∂μ = (∫⁻ (a : α), ENNReal.ofReal (f a) ∂μ).toReal

Tactic:
rw [integral_undef hfi]

Goal state after:
case neg
α : Type u_1
m : MeasurableSpace α
μ : Measure α
f : α → ℝ
hf : 0 ≤ᵐ[μ] f
hfm : AEStronglyMeasurable f μ
hfi : ¬Integrable f μ
⊢ 0 = (∫⁻ (a : α), ENNReal.ofReal (f a) ∂μ).toReal
Module: Mathlib.MeasureTheory.Integral.Bochner.Basic

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
μ : Measure α
P : Type u_7
inst✝ : NormedAddCommGroup P
f : α → P
hf : AEStronglyMeasurable f μ
⊢ ∫ (x : α), ‖f x‖ ∂μ = (∫⁻ (x : α), ‖f x‖ₑ ∂μ).toReal

Tactic:
rw [integral_eq_lintegral_of_nonneg_ae _ hf.norm]
  · simp_rw [ofReal_norm]
  · filter_upwards; simp_rw [Pi.zero_apply, norm_nonneg, imp_true_iff]

Goal state after:
Module: Mathlib.Analysis.Normed.Group.AddTorsor

Goal state before:
pp: α : Type u_1
V✝ : Type u_2
P✝ : Type u_3
W : Type u_4
Q : Type u_5
inst✝⁷ : SeminormedAddCommGroup V✝
inst✝⁶ : PseudoMetricSpace P✝
inst✝⁵ : NormedAddTorsor V✝ P✝
inst✝⁴ : SeminormedAddCommGroup W
inst✝³ : PseudoMetricSpace Q
inst✝² : NormedAddTorsor W Q
V : Type u_6
P : Type u_7
inst✝¹ : SeminormedAddCommGroup V
inst✝ : AddTorsor V P
x y : P
⊢ ‖x -ᵥ y‖ = ‖y -ᵥ x‖

Tactic:
by simp only [← neg_vsub_eq_vsub_rev y x, norm_neg]

Goal state after:
Module: Mathlib.Analysis.Normed.Group.AddTorsor

Goal state before:
pp: α : Type u_1
V✝ : Type u_2
P✝ : Type u_3
W : Type u_4
Q : Type u_5
inst✝⁷ : SeminormedAddCommGroup V✝
inst✝⁶ : PseudoMetricSpace P✝
inst✝⁵ : NormedAddTorsor V✝ P✝
inst✝⁴ : SeminormedAddCommGroup W
inst✝³ : PseudoMetricSpace Q
inst✝² : NormedAddTorsor W Q
V : Type u_6
P : Type u_7
inst✝¹ : NormedAddCommGroup V
inst✝ : AddTorsor V P
x y : P
⊢ ‖x -ᵥ y‖ = ‖y -ᵥ x‖

Tactic:
by simp only [← neg_vsub_eq_vsub_rev y x, norm_neg]

Goal state after:
Module: Mathlib.Analysis.Normed.Module.RieszLemma

Goal state before:
pp: case inr
F : Type u_3
inst✝¹ : SeminormedAddCommGroup F
inst✝ : NormedSpace ℝ F
x : F
s : Set F
hx : x ∈ s
h₀ : infDist x sᶜ ≠ 0
⊢ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (ball x (infDist x sᶜ)) ⊆
    closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] s

Tactic:
exact closure_mono ball_infDist_compl_subset

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.SumMeasure

Goal state before:
pp: case pos
ι : Type u_1
X : Type u_2
E : Type u_3
inst✝⁴ : Countable ι
mX : MeasurableSpace X
inst✝³ : NormedAddCommGroup E
f : X → E
inst✝² : NormedSpace ℝ E
inst✝¹ : MeasurableSingletonClass X
x : ι → X
c : ι → ℝ≥0∞
inst✝ : FiniteDimensional ℝ E
hc : ∀ (i : ι), c i ≠ ∞
hf : Integrable f (Measure.sum fun i ↦ c i • Measure.dirac (x i))
⊢ ∑' (i : ι), ∫ (x : X), f x ∂c i • Measure.dirac (x i) = ∑' (i : ι), (c i).toReal • f (x i)

Tactic:
congr with i

Goal state after:
case pos.e_f
ι : Type u_1
X : Type u_2
E : Type u_3
inst✝⁴ : Countable ι
mX : MeasurableSpace X
inst✝³ : NormedAddCommGroup E
f : X → E
inst✝² : NormedSpace ℝ E
inst✝¹ : MeasurableSingletonClass X
x : ι → X
c : ι → ℝ≥0∞
inst✝ : FiniteDimensional ℝ E
hc : ∀ (i : ι), c i ≠ ∞
hf : Integrable f (Measure.sum fun i ↦ c i • Measure.dirac (x i))
i : ι
⊢ ∫ (x : X), f x ∂c i • Measure.dirac (x i) = (c i).toReal • f (x i)
Module: Mathlib.MeasureTheory.Integral.SetToL1

Goal state before:
pp: case refine_1
α : Type u_1
E : Type u_2
F : Type u_3
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
m : MeasurableSpace α
μ : Measure α
T : Set α → E →L[ℝ] F
C : ℝ
hT : DominatedFinMeasAdditive μ T C
ι : Type u_7
s : Finset ι
f : ι → α → E
⊢ (∀ i ∈ ∅, Integrable (f i) μ) → setToFun μ T hT (∑ i ∈ ∅, f i) = ∑ i ∈ ∅, setToFun μ T hT (f i)

Tactic:
intro _
    simp only [setToFun_zero, Finset.sum_empty]

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.SumMeasure

Goal state before:
pp: X : Type u_2
E : Type u_3
mX : MeasurableSpace X
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
inst✝² : CompleteSpace E
inst✝¹ : MeasurableSingletonClass X
inst✝ : Fintype X
f : X → E
⊢ ∫ (x : X), f x ∂Measure.count = ∑ a, f a

Tactic:
simp [integral_fintype]

Goal state after:
Module: Mathlib.Topology.Bornology.BoundedOperation

Goal state before:
pp: R : Type u_2
inst✝² : Bornology R
inst✝¹ : Monoid R
inst✝ : BoundedMul R
s : Set R
s_bdd : Bornology.IsBounded s
n : ℕ
⊢ Bornology.IsBounded ((fun x ↦ x ^ n) '' s)

Tactic:
induction n with
  | zero =>
    by_cases s_empty : s = ∅
    · simp [s_empty]
    simp_rw [← nonempty_iff_ne_empty] at s_empty
    simp [s_empty]
  | succ n hn =>
    have obs : ((fun x ↦ x ^ (n + 1)) '' s) ⊆ ((fun x ↦ x ^ n) '' s) * s := by
      intro x hx
      simp only [mem_image] at hx
      obtain ⟨y, y_in_s, ypow_eq_x⟩ := hx
      rw [← ypow_eq_x, pow_succ y n]
      apply Set.mul_mem_mul _ y_in_s
      use y
    exact (isBounded_mul hn s_bdd).subset obs

Goal state after:
Module: Mathlib.MeasureTheory.Integral.SetToL1

Goal state before:
pp: case neg
α : Type u_1
E : Type u_2
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace ℝ E
m : MeasurableSpace α
μ : Measure α
G'' : Type u_8
inst✝⁴ : NormedAddCommGroup G''
inst✝³ : PartialOrder G''
inst✝² : IsOrderedAddMonoid G''
inst✝¹ : NormedSpace ℝ G''
inst✝ : OrderClosedTopology G''
T T' : Set α → E →L[ℝ] G''
C C' : ℝ
hT : DominatedFinMeasAdditive μ T C
hT' : DominatedFinMeasAdditive μ T' C'
hTT' : ∀ (s : Set α), MeasurableSet s → μ s < ∞ → ∀ (x : E), (T s) x ≤ (T' s) x
f : α → E
hG'' : CompleteSpace G''
hf : ¬Integrable f μ
⊢ setToFun μ T hT f ≤ setToFun μ T' hT' f

Tactic:
simp_rw [setToFun_undef _ hf, le_rfl]

Goal state after:
Module: Mathlib.Analysis.Normed.Module.FiniteDimension

Goal state before:
pp: 𝕜 : Type u
inst✝⁷ : NontriviallyNormedField 𝕜
E : Type v
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace 𝕜 E
F : Type w
inst✝⁴ : NormedAddCommGroup F
inst✝³ : NormedSpace 𝕜 F
inst✝² : CompleteSpace 𝕜
ι : Type u_1
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
g : ι → E
t : ι → 𝕜
⊢ ∑ i, ‖t i • g i‖ ≤ Fintype.card ι • ‖g‖ * ‖t‖

Tactic:
smul_mul_assoc

Goal state after:
𝕜 : Type u
inst✝⁷ : NontriviallyNormedField 𝕜
E : Type v
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace 𝕜 E
F : Type w
inst✝⁴ : NormedAddCommGroup F
inst✝³ : NormedSpace 𝕜 F
inst✝² : CompleteSpace 𝕜
ι : Type u_1
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
g : ι → E
t : ι → 𝕜
⊢ ∑ i, ‖t i • g i‖ ≤ Fintype.card ι • (‖g‖ * ‖t‖)
Module: Mathlib.Analysis.Normed.Module.FiniteDimension

Goal state before:
pp: 𝕜 : Type u
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type v
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type w
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
inst✝¹ : CompleteSpace 𝕜
ι : Type u_1
inst✝ : Fintype ι
v : Basis ι 𝕜 E
u : E →L[𝕜] F
M : ℝ≥0
hu : ∀ (i : ι), ‖u (v i)‖₊ ≤ M
e : E
φ : E →L[𝕜] ι → 𝕜 := ↑v.equivFunL
⊢ ‖u e‖₊ = ‖u (∑ i, v.equivFun e i • v i)‖₊

Tactic:
rw [v.sum_equivFun]

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Bounded.Basic

Goal state before:
pp: F : Type u_1
α : Type u
β : Type v
γ : Type w
𝕜 : Type u_2
inst✝⁶ : PseudoMetricSpace 𝕜
inst✝⁵ : TopologicalSpace α
inst✝⁴ : PseudoMetricSpace β
inst✝³ : Zero 𝕜
inst✝² : Zero β
inst✝¹ : SMul 𝕜 β
inst✝ : IsBoundedSMul 𝕜 β
c : 𝕜
f : α →ᵇ β
b : ℝ
hb : ∀ (x y : α), dist (f x) (f y) ≤ b
x y : α
⊢ dist ((c • f.toContinuousMap).toFun x) ((c • f.toContinuousMap).toFun y) ≤ dist c 0 * b

Tactic:
refine (dist_smul_pair c (f x) (f y)).trans ?_

Goal state after:
F : Type u_1
α : Type u
β : Type v
γ : Type w
𝕜 : Type u_2
inst✝⁶ : PseudoMetricSpace 𝕜
inst✝⁵ : TopologicalSpace α
inst✝⁴ : PseudoMetricSpace β
inst✝³ : Zero 𝕜
inst✝² : Zero β
inst✝¹ : SMul 𝕜 β
inst✝ : IsBoundedSMul 𝕜 β
c : 𝕜
f : α →ᵇ β
b : ℝ
hb : ∀ (x y : α), dist (f x) (f y) ≤ b
x y : α
⊢ dist c 0 * dist (f x) (f y) ≤ dist c 0 * b
Module: Mathlib.Topology.ContinuousMap.Bounded.Normed

Goal state before:
pp: α : Type u
inst✝² : TopologicalSpace α
R : Type u_1
inst✝¹ : NonUnitalSeminormedRing R
inst✝ : IsCancelMulZero R
f g : α →ᵇ R
h : f * g = 0
⊢ ‖f + g‖ = max ‖f‖ ‖g‖

Tactic:
have hfg : ∀ x, f x = 0 ∨ g x = 0 := by simpa [DFunLike.ext_iff, mul_eq_zero] using h

Goal state after:
α : Type u
inst✝² : TopologicalSpace α
R : Type u_1
inst✝¹ : NonUnitalSeminormedRing R
inst✝ : IsCancelMulZero R
f g : α →ᵇ R
h : f * g = 0
hfg : ∀ (x : α), f x = 0 ∨ g x = 0
⊢ ‖f + g‖ = max ‖f‖ ‖g‖
Module: Mathlib.Analysis.Normed.Module.FiniteDimension

Goal state before:
pp: 𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : SeminormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
inst✝ : LocallyCompactSpace E
r : ℝ
rpos : 0 < r
hr : IsCompact (closedBall 0 r)
c : 𝕜
hc : 1 < ‖c‖
n : ℕ
h : c = 0
⊢ False

Tactic:
simp [h, zero_le_one.not_gt] at hc

Goal state after:
Module: Mathlib.MeasureTheory.Integral.SetToL1

Goal state before:
pp: α : Type u_1
G : Type u_5
inst✝ : NormedAddCommGroup G
m : MeasurableSpace α
μ μ' : Measure α
c' : ℝ≥0∞
hc' : c' ≠ ∞
hμ'_le : μ' ≤ c' • μ
hc'0 : ¬c' = 0
f : ↥(Lp G 1 μ)
ε : ℝ
hε_pos : ε > 0
g : ↥(Lp G 1 μ)
hfg : (eLpNorm (↑↑g - ↑↑f) 1 μ).toReal < ε / 2 / c'.toReal
h_int : ∀ (f' : ↥(Lp G 1 μ)), Integrable (↑↑f') μ' :=
  fun f' ↦ Integrable.of_measure_le_smul hc' hμ'_le (L1.integrable_coeFn f')
this : eLpNorm (↑↑(Integrable.toL1 ↑↑g ⋯) - ↑↑(Integrable.toL1 ↑↑f ⋯)) 1 μ' = eLpNorm (↑↑g - ↑↑f) 1 μ'
⊢ eLpNorm (↑↑g - ↑↑f) 1 μ ≠ ∞

Tactic:
rw [← eLpNorm_congr_ae (Lp.coeFn_sub _ _)]

Goal state after:
α : Type u_1
G : Type u_5
inst✝ : NormedAddCommGroup G
m : MeasurableSpace α
μ μ' : Measure α
c' : ℝ≥0∞
hc' : c' ≠ ∞
hμ'_le : μ' ≤ c' • μ
hc'0 : ¬c' = 0
f : ↥(Lp G 1 μ)
ε : ℝ
hε_pos : ε > 0
g : ↥(Lp G 1 μ)
hfg : (eLpNorm (↑↑g - ↑↑f) 1 μ).toReal < ε / 2 / c'.toReal
h_int : ∀ (f' : ↥(Lp G 1 μ)), Integrable (↑↑f') μ' :=
  fun f' ↦ Integrable.of_measure_le_smul hc' hμ'_le (L1.integrable_coeFn f')
this : eLpNorm (↑↑(Integrable.toL1 ↑↑g ⋯) - ↑↑(Integrable.toL1 ↑↑f ⋯)) 1 μ' = eLpNorm (↑↑g - ↑↑f) 1 μ'
⊢ eLpNorm (↑↑(g - f)) 1 μ ≠ ∞
Module: Mathlib.Topology.MetricSpace.ThickenedIndicator

Goal state before:
pp: case pos
α : Type u_1
inst✝ : PseudoEMetricSpace α
δseq : ℕ → ℝ
δseq_lim : Tendsto δseq atTop (𝓝 0)
E : Set α
x : α
x_mem_closure : x ∈ closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] E
⊢ Tendsto (fun i ↦ 1) atTop
    (𝓝 ((closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] E).indicator (fun x ↦ 1) x))

Tactic:
show (indicator (closure E) fun _ => (1 : ℝ≥0∞)) x = 1 by
        simp only [x_mem_closure, indicator_of_mem]

Goal state after:
case pos
α : Type u_1
inst✝ : PseudoEMetricSpace α
δseq : ℕ → ℝ
δseq_lim : Tendsto δseq atTop (𝓝 0)
E : Set α
x : α
x_mem_closure : x ∈ closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] E
⊢ Tendsto (fun i ↦ 1) atTop (𝓝 1)
Module: Mathlib.MeasureTheory.Integral.Marginal

Goal state before:
pp: case inl
δ : Type u_1
X : δ → Type u_3
inst✝³ : (i : δ) → MeasurableSpace (X i)
μ : (i : δ) → Measure (X i)
inst✝² : DecidableEq δ
inst✝¹ : ∀ (i : δ), SigmaFinite (μ i)
inst✝ : Fintype δ
s : Finset δ
f g : ((i : δ) → X i) → ℝ≥0∞
hf : Measurable f
hg : Measurable g
hfg : ∫⋯∫⁻_s, f ∂μ = ∫⋯∫⁻_s, g ∂μ
h : IsEmpty ((i : δ) → X i)
⊢ ∫⁻ (x : (i : δ) → X i), f x ∂Measure.pi μ = ∫⁻ (x : (i : δ) → X i), g x ∂Measure.pi μ

pp: case inr
δ : Type u_1
X : δ → Type u_3
inst✝³ : (i : δ) → MeasurableSpace (X i)
μ : (i : δ) → Measure (X i)
inst✝² : DecidableEq δ
inst✝¹ : ∀ (i : δ), SigmaFinite (μ i)
inst✝ : Fintype δ
s : Finset δ
f g : ((i : δ) → X i) → ℝ≥0∞
hf : Measurable f
hg : Measurable g
hfg : ∫⋯∫⁻_s, f ∂μ = ∫⋯∫⁻_s, g ∂μ
x : (i : δ) → X i
⊢ ∫⁻ (x : (i : δ) → X i), f x ∂Measure.pi μ = ∫⁻ (x : (i : δ) → X i), g x ∂Measure.pi μ

Tactic:
· simp_rw [lintegral_of_isEmpty]

Goal state after:
case inr
δ : Type u_1
X : δ → Type u_3
inst✝³ : (i : δ) → MeasurableSpace (X i)
μ : (i : δ) → Measure (X i)
inst✝² : DecidableEq δ
inst✝¹ : ∀ (i : δ), SigmaFinite (μ i)
inst✝ : Fintype δ
s : Finset δ
f g : ((i : δ) → X i) → ℝ≥0∞
hf : Measurable f
hg : Measurable g
hfg : ∫⋯∫⁻_s, f ∂μ = ∫⋯∫⁻_s, g ∂μ
x : (i : δ) → X i
⊢ ∫⁻ (x : (i : δ) → X i), f x ∂Measure.pi μ = ∫⁻ (x : (i : δ) → X i), g x ∂Measure.pi μ
Module: Mathlib.MeasureTheory.Integral.Bochner.Set

Goal state before:
pp: X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s : Set X
μ : Measure X
hs : NullMeasurableSet s μ
hfi : Integrable f μ
⊢ ∫ (x : X) in s, f x ∂μ + ∫ (x : X) in sᶜ, f x ∂μ = ∫ (x : X), f x ∂μ

Tactic:
have := setIntegral_union₀ disjoint_compl_right.aedisjoint
    hs.compl hfi.integrableOn hfi.integrableOn

Goal state after:
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s : Set X
μ : Measure X
hs : NullMeasurableSet s μ
hfi : Integrable f μ
this : ∫ (x : X) in s ∪ sᶜ, f x ∂μ = ∫ (x : X) in s, f x ∂μ + ∫ (x : X) in sᶜ, f x ∂μ
⊢ ∫ (x : X) in s, f x ∂μ + ∫ (x : X) in sᶜ, f x ∂μ = ∫ (x : X), f x ∂μ
Module: Mathlib.MeasureTheory.Integral.Bochner.Set

Goal state before:
pp: X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s : Set X
μ : Measure X
hs : NullMeasurableSet s μ
hfi : Integrable f μ
this : ∫ (x : X) in s ∪ sᶜ, f x ∂μ = ∫ (x : X) in s, f x ∂μ + ∫ (x : X) in sᶜ, f x ∂μ
⊢ ∫ (x : X) in s, f x ∂μ + ∫ (x : X) in sᶜ, f x ∂μ = ∫ (x : X), f x ∂μ

Tactic:
rw [← this, union_compl_self, setIntegral_univ]

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

Goal state before:
pp: case inr
R : Type u_1
inst✝³ : LinearOrder R
inst✝² : TopologicalSpace R
f : StieltjesFunction R
inst✝¹ : OrderTopology R
inst✝ : CompactIccSpace R
a : R
c d : ℕ → R
s✝ s : Finset ℕ
IH :
  ∀ t ⊂ s,
    ∀ (b : R), Icc a b ⊆ ⋃ i ∈ ↑t, Iotop (c i) (d i) → ofReal (↑f b - ↑f a) ≤ ∑ i ∈ t, ofReal (↑f (d i) - ↑f (c i))
b : R
ab : a ≤ b
i : ℕ
cv : Icc a b ⊆ Iotop (c i) (d i) ∪ ⋃ x ∈ ↑(s.erase i), Iotop (c x) (d x)
is : i ∈ s
bcd : b ∈ Ioc (c i) (d i)
⊢ ofReal (↑f b - ↑f a) ≤ ofReal (↑f (d i) - ↑f a)

Tactic:
grw [bcd.2]

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

Goal state before:
pp: G : Type w
inst✝² : TopologicalSpace G
μ : Content G
inst✝¹ : Group G
inst✝ : SeparatelyContinuousMul G
h : ∀ (g : G) {K : Compacts G}, μ (Compacts.map (fun x ↦ g * x) ⋯ K) = μ K
g : G
U : Opens G
⊢ μ.innerContent ((Opens.comap ↑(Homeomorph.mulLeft g)) U) = μ.innerContent U

Tactic:
by
  convert! μ.innerContent_comap (Homeomorph.mulLeft g) (fun K => h g) U

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.Set

Goal state before:
pp: X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s t : Set X
μ : Measure X
hts : s ⊆ t
h't : ∀ᵐ (x : X) ∂μ, x ∈ t \ s → f x = 0
haux : StronglyMeasurable f
h'aux : IntegrableOn f t μ
k : Set X := f ⁻¹' {0}
hk : MeasurableSet k
⊢ ∫ (x : X) in t \ k, f x ∂μ = ∫ (x : X) in s \ k, f x ∂μ

Tactic:
apply setIntegral_congr_set
      filter_upwards [h't] with x hx
      change (x ∈ t \ k) = (x ∈ s \ k)
      simp only [eq_iff_iff, and_congr_left_iff, Set.mem_sdiff]
      intro h'x
      by_cases xs : x ∈ s
      · simp only [xs, hts xs]
      · simp only [xs, iff_false]
        intro xt
        exact h'x (hx ⟨xt, xs⟩)

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.Set

Goal state before:
pp: X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s t : Set X
μ : Measure X
ht : NullMeasurableSet t μ
hts : s ⊆ t
h't : ∀ᵐ (x : X) ∂μ, x ∈ t \ s → f x = 0
h : IntegrableOn f t μ
f' : X → E := AEStronglyMeasurable.mk f ⋯
x : X
hx : x ∈ t \ s → f x = 0
h'x : x ∈ t → f x = AEStronglyMeasurable.mk f ⋯ x
h''x : x ∈ t \ s
⊢ AEStronglyMeasurable.mk f ⋯ x = 0

Tactic:
rw [← h'x h''x.1, hx h''x]

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.Set

Goal state before:
pp: X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
μ : Measure X
inst✝ : PartialOrder E
f : X → E
hf : AEStronglyMeasurable f μ
h_union : {x | f x ≤ 0} = {x | f x < 0} ∪ {x | f x = 0}
⊢ ∫ (x : X) in {x | f x < 0}, f x ∂μ = ∫ (x : X) in {x | f x < 0} ∪ {x | f x = 0}, f x ∂μ

Tactic:
have B : NullMeasurableSet {x | f x = 0} μ :=
    hf.nullMeasurableSet_eq_fun aestronglyMeasurable_zero

Goal state after:
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
μ : Measure X
inst✝ : PartialOrder E
f : X → E
hf : AEStronglyMeasurable f μ
h_union : {x | f x ≤ 0} = {x | f x < 0} ∪ {x | f x = 0}
B : NullMeasurableSet {x | f x = 0} μ
⊢ ∫ (x : X) in {x | f x < 0}, f x ∂μ = ∫ (x : X) in {x | f x < 0} ∪ {x | f x = 0}, f x ∂μ
Module: Mathlib.MeasureTheory.Integral.Bochner.Set

Goal state before:
pp: case neg
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s : Set X
μ : Measure X
C : ℝ
hs : μ s < ∞
hC : ∀ᵐ (x : X) ∂μ, x ∈ s → ‖f x‖ ≤ C
hfm : ¬AEStronglyMeasurable f (μ.restrict s)
⊢ ‖0‖ ≤ C * μ.real s

Tactic:
have : ∃ᵐ (x : X) ∂μ, x ∈ s := by
      apply frequently_ae_mem_iff.mpr
      contrapose hfm
      simp [Measure.restrict_eq_zero.mpr hfm]

Goal state after:
case neg
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s : Set X
μ : Measure X
C : ℝ
hs : μ s < ∞
hC : ∀ᵐ (x : X) ∂μ, x ∈ s → ‖f x‖ ≤ C
hfm : ¬AEStronglyMeasurable f (μ.restrict s)
this : ∃ᵐ (x : X) ∂μ, x ∈ s
⊢ ‖0‖ ≤ C * μ.real s
Module: Mathlib.MeasureTheory.Measure.Stieltjes

Goal state before:
pp: case inr
R : Type u_1
inst✝⁷ : LinearOrder R
inst✝⁶ : TopologicalSpace R
f : StieltjesFunction R
inst✝⁵ : OrderTopology R
inst✝⁴ : CompactIccSpace R
inst✝³ : MeasurableSpace R
inst✝² : BorelSpace R
inst✝¹ : SecondCountableTopology R
inst✝ : DenselyOrdered R
a b : R
hab : b < a
⊢ f.measure (Icc a b) = ofReal (↑f b - leftLim (↑f) a)

Tactic:
simp only [hab, measure_empty, Icc_eq_empty, not_le]

Goal state after:
case inr
R : Type u_1
inst✝⁷ : LinearOrder R
inst✝⁶ : TopologicalSpace R
f : StieltjesFunction R
inst✝⁵ : OrderTopology R
inst✝⁴ : CompactIccSpace R
inst✝³ : MeasurableSpace R
inst✝² : BorelSpace R
inst✝¹ : SecondCountableTopology R
inst✝ : DenselyOrdered R
a b : R
hab : b < a
⊢ 0 = ofReal (↑f b - leftLim (↑f) a)
Module: Mathlib.MeasureTheory.Integral.Bochner.Set

Goal state before:
pp: case hf
X : Type u_1
mX : MeasurableSpace X
μ : Measure X
R : ℝ
f : X → ℝ
hR : 0 ≤ R
hfint : IntegrableOn f {x | R < f x} μ
hμ : μ {x | R < f x} ≠ 0
this : IntegrableOn (fun x ↦ R) {x | R < f x} μ
⊢ 0 ≤ᵐ[μ.restrict {x | R < f x}] fun a ↦ f a - R

Tactic:
rw [Pi.zero_def, EventuallyLE, ae_restrict_iff₀]
    · exact Eventually.of_forall fun x hx => sub_nonneg.2 <| le_of_lt hx
    · exact nullMeasurableSet_le aemeasurable_zero (hfint.1.aemeasurable.sub aemeasurable_const)

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Haar.Basic

Goal state before:
pp: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : IsTopologicalGroup G
K : Set G
hK : IsCompact K
V : Set G
hV : (interior V).Nonempty
g : G
s : Finset G
h1s : K ⊆ ⋃ g ∈ s, (fun h ↦ g * h) ⁻¹' V
h2s : s.card = index K V
⊢ (fun h ↦ g * h) '' K ⊆ ⋃ g_1 ∈ Finset.map (Equiv.toEmbedding (Equiv.mulRight g⁻¹)) s, (fun h ↦ g_1 * h) ⁻¹' V

Tactic:
refine Subset.trans (image_mono h1s) ?_

Goal state after:
G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : IsTopologicalGroup G
K : Set G
hK : IsCompact K
V : Set G
hV : (interior V).Nonempty
g : G
s : Finset G
h1s : K ⊆ ⋃ g ∈ s, (fun h ↦ g * h) ⁻¹' V
h2s : s.card = index K V
⊢ (fun h ↦ g * h) '' ⋃ g ∈ s, (fun h ↦ g * h) ⁻¹' V ⊆
    ⋃ g_1 ∈ Finset.map (Equiv.toEmbedding (Equiv.mulRight g⁻¹)) s, (fun h ↦ g_1 * h) ⁻¹' V