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MeanFourier.Mathlib.MeasureTheory.Integral.Average

theorem MeasureTheory.average_add {α : Type u_1} {E : Type u_2} {m0 : MeasurableSpace α} [NormedAddCommGroup E] [NormedSpace E] {μ : Measure α} {f g : αE} (hf : Integrable f μ) (hg : Integrable g μ) :
(a : α), (f + g) a μ = (a : α), f a μ + (a : α), g a μ
theorem MeasureTheory.average_fun_add {α : Type u_1} {E : Type u_2} {m0 : MeasurableSpace α} [NormedAddCommGroup E] [NormedSpace E] {μ : Measure α} {f g : αE} (hf : Integrable f μ) (hg : Integrable g μ) :
(a : α), f a + g a μ = (a : α), f a μ + (a : α), g a μ

Eta-expanded form of MeasureTheory.average_add

theorem MeasureTheory.setAverage_add {α : Type u_1} {E : Type u_2} {m0 : MeasurableSpace α} [NormedAddCommGroup E] [NormedSpace E] {μ : Measure α} {s : Set α} {f g : αE} (hf : IntegrableOn f s μ) (hg : IntegrableOn g s μ) :
(a : α) in s, (f + g) a μ = (a : α) in s, f a μ + (a : α) in s, g a μ
theorem MeasureTheory.setAverage_fun_add {α : Type u_1} {E : Type u_2} {m0 : MeasurableSpace α} [NormedAddCommGroup E] [NormedSpace E] {μ : Measure α} {s : Set α} {f g : αE} (hf : IntegrableOn f s μ) (hg : IntegrableOn g s μ) :
(a : α) in s, f a + g a μ = (a : α) in s, f a μ + (a : α) in s, g a μ

Eta-expanded form of MeasureTheory.setAverage_add

theorem MeasureTheory.average_const_mul {α : Type u_1} {m0 : MeasurableSpace α} {μ : Measure α} {L : Type u_3} [RCLike L] (r : L) (f : αL) :
(a : α), r * f a μ = r * (a : α), f a μ
@[simp]
theorem MeasureTheory.average_count {α : Type u_1} {E : Type u_2} {m0 : MeasurableSpace α} [NormedAddCommGroup E] [NormedSpace E] [Module ℚ≥0 E] [CompleteSpace E] [MeasurableSingletonClass α] [Fintype α] (f : αE) :
(a : α), f a Measure.count = Finset.univ.expect fun (a : α) => f a
theorem MeasureTheory.average_nonneg_of_ae {α : Type u_1} {E : Type u_2} {m0 : MeasurableSpace α} [NormedAddCommGroup E] [NormedSpace E] {μ : Measure α} {f : αE} [PartialOrder E] [IsOrderedAddMonoid E] [IsOrderedModule E] [ClosedIciTopology E] (hf : 0 ≤ᵐ[μ] f) :
0 (a : α), f a μ

The average of a function which is nonnegative almost everywhere is nonnegative.

theorem MeasureTheory.average_nonneg {α : Type u_1} {E : Type u_2} {m0 : MeasurableSpace α} [NormedAddCommGroup E] [NormedSpace E] {μ : Measure α} {f : αE} [PartialOrder E] [IsOrderedAddMonoid E] [IsOrderedModule E] [ClosedIciTopology E] (hf : 0 f) :
0 (a : α), f a μ