mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.MeasureTheory.Group.FundamentalDomain

Goal state before:
pp: G : Type u_1
α : Type u_3
inst✝⁴ : Group G
inst✝³ : MulAction G α
inst✝² : MeasurableSpace α
ν : Measure α
hasFun : HasFundamentalDomain G α ν
μ μ' : Measure (Quotient α_mod_G)
inst✝¹ : QuotientMeasureEqMeasurePreimage ν μ
inst✝ : QuotientMeasureEqMeasurePreimage ν μ'
𝓕 : Set α
h𝓕 : IsFundamentalDomain G 𝓕 ν
⊢ μ = μ'

Tactic:
rw [h𝓕.projection_respects_measure (μ := μ), h𝓕.projection_respects_measure (μ := μ')]

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
K₀ : PositiveCompacts G
K₁ K₂ : Compacts G
h : ↑K₁ ⊆ ↑K₂
⊢ chaar K₀ K₁ ≤ chaar K₀ K₂

Tactic:
by
  let eval : (Compacts G → ℝ) → ℝ := fun f => f K₂ - f K₁
  have : Continuous eval := (continuous_apply K₂).sub (continuous_apply K₁)
  rw [← sub_nonneg]; change chaar K₀ ∈ eval ⁻¹' Ici (0 : ℝ)
  apply mem_of_subset_of_mem _ (chaar_mem_clPrehaar K₀ ⊤)
  unfold clPrehaar; rw [IsClosed.closure_subset_iff]
  · rintro _ ⟨U, ⟨_, h2U, h3U⟩, rfl⟩; simp only [eval, mem_preimage, mem_Ici, sub_nonneg]
    apply prehaar_mono _ h; rw [h2U.interior_eq]; exact ⟨1, h3U⟩
  · apply continuous_iff_isClosed.mp this; exact isClosed_Ici

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Basic

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝² : RCLike 𝕜
inst✝¹ : SeminormedAddCommGroup E
inst✝ : InnerProductSpace 𝕜 E
x y : E
h : ‖x‖ = 0
⊢ ⟪x, y⟫ = 0

Tactic:
← norm_eq_zero

Goal state after:
𝕜 : Type u_1
E : Type u_2
inst✝² : RCLike 𝕜
inst✝¹ : SeminormedAddCommGroup E
inst✝ : InnerProductSpace 𝕜 E
x y : E
h : ‖x‖ = 0
⊢ ‖⟪x, y⟫‖ = 0
Module: Mathlib.Analysis.InnerProductSpace.Basic

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝² : RCLike 𝕜
inst✝¹ : NormedAddCommGroup E
inst✝ : InnerProductSpace 𝕜 E
x y : E
h : ‖⟪x, y⟫ / (↑‖x‖ * ↑‖y‖)‖ = 1
h₀ : x = 0
⊢ False

Tactic:
simp [h₀] at h

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Projection.Minimal

Goal state before:
pp: case a
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : InnerProductSpace ℝ F
K : Set F
h : Convex ℝ K
u v : F
hv : v ∈ K
this : Nonempty ↑K := ⋯
eq : ‖u - v‖ = ⨅ w, ‖u - ↑w‖
w : F
hw : w ∈ K
δ : ℝ := ⋯
p : ℝ := ⋯
q : ℝ := ⋯
δ_le : ∀ (w : ↑K), δ ≤ ‖u - ↑w‖
δ_le' : ∀ w ∈ K, δ ≤ ‖u - w‖
θ : ℝ
hθ₁ : 0 < θ
hθ₂ : θ ≤ 1
⊢ 0 ≤ θ

pp: case a
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : InnerProductSpace ℝ F
K : Set F
h : Convex ℝ K
u v : F
hv : v ∈ K
this : Nonempty ↑K := ⋯
eq : ‖u - v‖ = ⨅ w, ‖u - ↑w‖
w : F
hw : w ∈ K
δ : ℝ := ⋯
p : ℝ := ⋯
q : ℝ := ⋯
δ_le : ∀ (w : ↑K), δ ≤ ‖u - ↑w‖
δ_le' : ∀ w ∈ K, δ ≤ ‖u - w‖
θ : ℝ
hθ₁ : 0 < θ
hθ₂ : θ ≤ 1
⊢ 0 ≤ 1 - θ

pp: case a
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : InnerProductSpace ℝ F
K : Set F
h : Convex ℝ K
u v : F
hv : v ∈ K
this : Nonempty ↑K := ⋯
eq : ‖u - v‖ = ⨅ w, ‖u - ↑w‖
w : F
hw : w ∈ K
δ : ℝ := ⋯
p : ℝ := ⋯
q : ℝ := ⋯
δ_le : ∀ (w : ↑K), δ ≤ ‖u - ↑w‖
δ_le' : ∀ w ∈ K, δ ≤ ‖u - w‖
θ : ℝ
hθ₁ : 0 < θ
hθ₂ : θ ≤ 1
⊢ θ + (1 - θ) = 1

Tactic:
exacts [le_of_lt hθ₁, sub_nonneg.2 hθ₂, add_sub_cancel _ _]

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Basic

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝² : RCLike 𝕜
inst✝¹ : NormedAddCommGroup E
inst✝ : InnerProductSpace 𝕜 E
x y : E
h : ‖⟪x, y⟫ / (↑‖x‖ * ↑‖y‖)‖ = 1
hx₀ : x ≠ 0
h₀ : y = 0
⊢ False

Tactic:
simp [h₀] at h

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Basic

Goal state before:
pp: F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : InnerProductSpace ℝ F
x y : F
h : ⟪x, y⟫_ℝ / (‖x‖ * ‖y‖) = 1
h₀ : x = 0
⊢ False

Tactic:
simp [h₀] at h

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Basic

Goal state before:
pp: F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : InnerProductSpace ℝ F
x y : F
h : ⟪x, y⟫_ℝ / (‖x‖ * ‖y‖) = 1
hx₀ : x ≠ 0
h₀ : y = 0
⊢ False

Tactic:
simp [h₀] at h

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Orthonormal

Goal state before:
pp: case mpr
𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : SeminormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
ι : Type u_4
inst✝ : DecidableEq ι
v : ι → E
⊢ (∀ (i j : ι), ⟪v i, v j⟫ = if i = j then 1 else 0) → Orthonormal 𝕜 v

Tactic:
intro h
    constructor
    · intro i
      have h' : ‖v i‖ ^ 2 = 1 ^ 2 := by
        rw [@norm_sq_eq_re_inner 𝕜, h i i]; simp
      have h₁ : 0 ≤ ‖v i‖ := norm_nonneg _
      have h₂ : (0 : ℝ) ≤ 1 := zero_le_one
      rwa [sq_eq_sq₀ h₁ h₂] at h'
    · intro i j hij
      simpa [hij] using h i j

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.LinearMap

Goal state before:
pp: 𝕜 : Type u_4
inst✝⁴ : RCLike 𝕜
F : Type u_8
H : Type u_9
inst✝³ : NormedAddCommGroup F
inst✝² : InnerProductSpace 𝕜 F
inst✝¹ : NormedAddCommGroup H
inst✝ : InnerProductSpace 𝕜 H
a c : F
b d : H
ha : a ≠ 0
hb : b ≠ 0
h : ∀ (x : H), ⟪b, x⟫_𝕜 • a = ⟪d, x⟫_𝕜 • c
h₂ : ∀ (x : F), ⟪a, x⟫_𝕜 • b = ⟪c, x⟫_𝕜 • d
h₃ : a = (⟪d, b⟫_𝕜 / ⟪b, b⟫_𝕜) • c
⊢ (1 / ⟪a, a⟫_𝕜) • ⟪a, a⟫_𝕜 • b = (⟪d, b⟫_𝕜 / ⟪b, b⟫_𝕜 * (⟪c, c⟫_𝕜 / ⟪a, a⟫_𝕜)) • d

Tactic:
simp_rw [h₂, h₃, inner_smul_right, smul_smul]; ring_nf

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Subspace

Goal state before:
pp: case h
𝕜 : Type u_1
E : Type u_2
inst✝⁵ : RCLike 𝕜
inst✝⁴ : SeminormedAddCommGroup E
inst✝³ : InnerProductSpace 𝕜 E
ι : Type u_4
G : ι → Type u_5
inst✝² : (i : ι) → NormedAddCommGroup (G i)
inst✝¹ : (i : ι) → InnerProductSpace 𝕜 (G i)
V : (i : ι) → G i →ₗᵢ[𝕜] E
hV : OrthogonalFamily 𝕜 G V
inst✝ : CompleteSpace E
f : (i : ι) → G i
hf : ∀ ε > 0, ∃ N, ∀ (m : Finset ι), N ⊆ m → ∀ (n : Finset ι), N ⊆ n → ‖∑ i ∈ m, (V i) (f i) - ∑ i ∈ n, (V i) (f i)‖ < ε
ε : ℝ
hε : ε > 0
a : Finset ι
H : ∀ (m : Finset ι), a ⊆ m → ∀ (n : Finset ι), a ⊆ n → ‖∑ i ∈ m, (V i) (f i) - ∑ i ∈ n, (V i) (f i)‖ < √ε
s₁ : Finset ι
hs₁ : a ⊆ s₁
s₂ : Finset ι
hs₂ : a ⊆ s₂
⊢ |∑ i ∈ s₁, ‖f i‖ ^ 2 - ∑ i ∈ s₂, ‖f i‖ ^ 2| < ε

Tactic:
rw [← Finset.sum_sdiff_sub_sum_sdiff]

Goal state after:
case h
𝕜 : Type u_1
E : Type u_2
inst✝⁵ : RCLike 𝕜
inst✝⁴ : SeminormedAddCommGroup E
inst✝³ : InnerProductSpace 𝕜 E
ι : Type u_4
G : ι → Type u_5
inst✝² : (i : ι) → NormedAddCommGroup (G i)
inst✝¹ : (i : ι) → InnerProductSpace 𝕜 (G i)
V : (i : ι) → G i →ₗᵢ[𝕜] E
hV : OrthogonalFamily 𝕜 G V
inst✝ : CompleteSpace E
f : (i : ι) → G i
hf : ∀ ε > 0, ∃ N, ∀ (m : Finset ι), N ⊆ m → ∀ (n : Finset ι), N ⊆ n → ‖∑ i ∈ m, (V i) (f i) - ∑ i ∈ n, (V i) (f i)‖ < ε
ε : ℝ
hε : ε > 0
a : Finset ι
H : ∀ (m : Finset ι), a ⊆ m → ∀ (n : Finset ι), a ⊆ n → ‖∑ i ∈ m, (V i) (f i) - ∑ i ∈ n, (V i) (f i)‖ < √ε
s₁ : Finset ι
hs₁ : a ⊆ s₁
s₂ : Finset ι
hs₂ : a ⊆ s₂
⊢ |∑ x ∈ s₁ \ s₂, ‖f x‖ ^ 2 - ∑ x ∈ s₂ \ s₁, ‖f x‖ ^ 2| < ε
Module: Mathlib.Topology.Algebra.Module.ClosedSubmodule

Goal state before:
pp: case refine_2
ι : Sort u_1
R : Type u_2
M : Type u_3
N : Type u_4
O : Type u_5
inst✝¹¹ : Semiring R
inst✝¹⁰ : AddCommMonoid M
inst✝⁹ : TopologicalSpace M
inst✝⁸ : Module R M
inst✝⁷ : AddCommMonoid N
inst✝⁶ : TopologicalSpace N
inst✝⁵ : Module R N
inst✝⁴ : AddCommMonoid O
inst✝³ : TopologicalSpace O
inst✝² : Module R O
inst✝¹ : ContinuousAdd N
inst✝ : ContinuousConstSMul R N
f : M →L[R] N
s t : ClosedSubmodule R N
x✝¹ : N
x✝ : Set (ClosedSubmodule R N)
a : ClosedSubmodule R N
h : a ∈ upperBounds x✝
x : N
⊢ ↑(⨆ s ∈ x✝, ↑s) ⊆ ↑a

Tactic:
intro y

Goal state after:
case refine_2
ι : Sort u_1
R : Type u_2
M : Type u_3
N : Type u_4
O : Type u_5
inst✝¹¹ : Semiring R
inst✝¹⁰ : AddCommMonoid M
inst✝⁹ : TopologicalSpace M
inst✝⁸ : Module R M
inst✝⁷ : AddCommMonoid N
inst✝⁶ : TopologicalSpace N
inst✝⁵ : Module R N
inst✝⁴ : AddCommMonoid O
inst✝³ : TopologicalSpace O
inst✝² : Module R O
inst✝¹ : ContinuousAdd N
inst✝ : ContinuousConstSMul R N
f : M →L[R] N
s t : ClosedSubmodule R N
x✝¹ : N
x✝ : Set (ClosedSubmodule R N)
a : ClosedSubmodule R N
h : a ∈ upperBounds x✝
x y : N
⊢ y ∈ ↑(⨆ s ∈ x✝, ↑s) → y ∈ ↑a
Module: Mathlib.Analysis.InnerProductSpace.Subspace

Goal state before:
pp: case h
𝕜 : Type u_1
E : Type u_2
inst✝⁵ : RCLike 𝕜
inst✝⁴ : SeminormedAddCommGroup E
inst✝³ : InnerProductSpace 𝕜 E
ι : Type u_4
G : ι → Type u_5
inst✝² : (i : ι) → NormedAddCommGroup (G i)
inst✝¹ : (i : ι) → InnerProductSpace 𝕜 (G i)
V : (i : ι) → G i →ₗᵢ[𝕜] E
hV : OrthogonalFamily 𝕜 G V
inst✝ : CompleteSpace E
f : (i : ι) → G i
hf : ∀ ε > 0, ∃ N, ∀ (m : Finset ι), N ⊆ m → ∀ (n : Finset ι), N ⊆ n → |∑ i ∈ m, ‖f i‖ ^ 2 - ∑ i ∈ n, ‖f i‖ ^ 2| < ε
ε : ℝ
hε : ε > 0
hε' : 0 < ε ^ 2 / 2
a : Finset ι
H : ∀ (m : Finset ι), a ⊆ m → ∀ (n : Finset ι), a ⊆ n → |∑ i ∈ m, ‖f i‖ ^ 2 - ∑ i ∈ n, ‖f i‖ ^ 2| < ε ^ 2 / 2
s₁ : Finset ι
hs₁ : a ⊆ s₁
s₂ : Finset ι
hs₂ : a ⊆ s₂
has : a ⊆ s₁ ⊓ s₂
⊢ ∑ i ∈ s₁ \ s₂, ‖f i‖ ^ 2 + ∑ i ∈ s₂ \ s₁, ‖f i‖ ^ 2 < ε ^ 2

Tactic:
have Hs₁ : ∑ x ∈ s₁ \ s₂, ‖f x‖ ^ 2 < ε ^ 2 / 2 := by
        convert! H _ hs₁ _ has
        have : s₁ ⊓ s₂ ⊆ s₁ := Finset.inter_subset_left
        rw [← Finset.sum_sdiff this, add_tsub_cancel_right, Finset.abs_sum_of_nonneg']
        · simp
        · exact fun i => sq_nonneg _

Goal state after:
case h
𝕜 : Type u_1
E : Type u_2
inst✝⁵ : RCLike 𝕜
inst✝⁴ : SeminormedAddCommGroup E
inst✝³ : InnerProductSpace 𝕜 E
ι : Type u_4
G : ι → Type u_5
inst✝² : (i : ι) → NormedAddCommGroup (G i)
inst✝¹ : (i : ι) → InnerProductSpace 𝕜 (G i)
V : (i : ι) → G i →ₗᵢ[𝕜] E
hV : OrthogonalFamily 𝕜 G V
inst✝ : CompleteSpace E
f : (i : ι) → G i
hf : ∀ ε > 0, ∃ N, ∀ (m : Finset ι), N ⊆ m → ∀ (n : Finset ι), N ⊆ n → |∑ i ∈ m, ‖f i‖ ^ 2 - ∑ i ∈ n, ‖f i‖ ^ 2| < ε
ε : ℝ
hε : ε > 0
hε' : 0 < ε ^ 2 / 2
a : Finset ι
H : ∀ (m : Finset ι), a ⊆ m → ∀ (n : Finset ι), a ⊆ n → |∑ i ∈ m, ‖f i‖ ^ 2 - ∑ i ∈ n, ‖f i‖ ^ 2| < ε ^ 2 / 2
s₁ : Finset ι
hs₁ : a ⊆ s₁
s₂ : Finset ι
hs₂ : a ⊆ s₂
has : a ⊆ s₁ ⊓ s₂
Hs₁ : ∑ x ∈ s₁ \ s₂, ‖f x‖ ^ 2 < ε ^ 2 / 2
⊢ ∑ i ∈ s₁ \ s₂, ‖f i‖ ^ 2 + ∑ i ∈ s₂ \ s₁, ‖f i‖ ^ 2 < ε ^ 2
Module: Mathlib.Analysis.InnerProductSpace.Symmetric

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝² : RCLike 𝕜
inst✝¹ : SeminormedAddCommGroup E
inst✝ : InnerProductSpace 𝕜 E
T S : E →ₗ[𝕜] E
hT : T.IsSymmetric
hS : S.IsSymmetric
x y : E
⊢ ⟪(T + S) x, y⟫ = ⟪x, (T + S) y⟫

Tactic:
add_apply,

Goal state after:
𝕜 : Type u_1
E : Type u_2
inst✝² : RCLike 𝕜
inst✝¹ : SeminormedAddCommGroup E
inst✝ : InnerProductSpace 𝕜 E
T S : E →ₗ[𝕜] E
hT : T.IsSymmetric
hS : S.IsSymmetric
x y : E
⊢ ⟪T x + S x, y⟫ = ⟪x, (T + S) y⟫
Module: Mathlib.Analysis.InnerProductSpace.Projection.Submodule

Goal state before:
pp: case refine_1
𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
K : Submodule 𝕜 E
inst✝ : CompleteSpace E
⊢ Kᗮᗮ ≤ K.topologicalClosure

pp: case refine_2
𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
K : Submodule 𝕜 E
inst✝ : CompleteSpace E
⊢ K.topologicalClosure ≤ Kᗮᗮ

Tactic:
· convert Submodule.orthogonal_orthogonal_monotone K.le_topologicalClosure
    rw [K.topologicalClosure.orthogonal_orthogonal]

Goal state after:
case refine_2
𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
K : Submodule 𝕜 E
inst✝ : CompleteSpace E
⊢ K.topologicalClosure ≤ Kᗮᗮ
Module: Mathlib.Analysis.InnerProductSpace.Projection.FiniteDimensional

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
K₁ K₂ : Submodule 𝕜 E
inst✝ : FiniteDimensional 𝕜 ↥K₂
h : K₁ ≤ K₂
n : ℕ
h_dim : finrank 𝕜 ↥K₁ + n = finrank 𝕜 ↥K₂
⊢ finrank 𝕜 ↥K₁ + finrank 𝕜 ↥(K₁ᗮ ⊓ K₂) = finrank 𝕜 ↥K₁ + n

Tactic:
simp [Submodule.finrank_add_inf_finrank_orthogonal h, h_dim]

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Projection.Basic

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
K : Submodule 𝕜 E
inst✝ : K.HasOrthogonalProjection
v : E
⊢ 0 ≤ re ⟪K.starProjection v, v⟫

Tactic:
rw [re_inner_starProjection_eq_normSq K v]

Goal state after:
𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
K : Submodule 𝕜 E
inst✝ : K.HasOrthogonalProjection
v : E
⊢ 0 ≤ ‖K.orthogonalProjectionOnto v‖ ^ 2
Module: Mathlib.Analysis.Normed.Operator.Banach

Goal state before:
pp: 𝕜 : Type u_1
𝕜' : Type u_2
inst✝¹⁰ : NontriviallyNormedField 𝕜
inst✝⁹ : NontriviallyNormedField 𝕜'
σ : 𝕜 →+* 𝕜'
E : Type u_3
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_4
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜' F
f : E →SL[σ] F
σ' : 𝕜' →+* 𝕜
inst✝⁴ : RingHomInvPair σ σ'
inst✝³ : RingHomIsometric σ
inst✝² : RingHomIsometric σ'
inst✝¹ : CompleteSpace F
inst✝ : CompleteSpace E
surj : Surjective ⇑f
C : ℝ
C0 : C ≥ 0
g : F → E
hg : ∀ (y : F), dist (f (g y)) y ≤ 1 / 2 * ‖y‖ ∧ ‖g y‖ ≤ C * ‖y‖
h : F → F := fun y ↦ y - f (g y)
⊢ ∀ (y : F), ‖h y‖ ≤ 1 / 2 * ‖y‖

Tactic:
intro y

Goal state after:
𝕜 : Type u_1
𝕜' : Type u_2
inst✝¹⁰ : NontriviallyNormedField 𝕜
inst✝⁹ : NontriviallyNormedField 𝕜'
σ : 𝕜 →+* 𝕜'
E : Type u_3
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_4
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜' F
f : E →SL[σ] F
σ' : 𝕜' →+* 𝕜
inst✝⁴ : RingHomInvPair σ σ'
inst✝³ : RingHomIsometric σ
inst✝² : RingHomIsometric σ'
inst✝¹ : CompleteSpace F
inst✝ : CompleteSpace E
surj : Surjective ⇑f
C : ℝ
C0 : C ≥ 0
g : F → E
hg : ∀ (y : F), dist (f (g y)) y ≤ 1 / 2 * ‖y‖ ∧ ‖g y‖ ≤ C * ‖y‖
h : F → F := fun y ↦ y - f (g y)
y : F
⊢ ‖h y‖ ≤ 1 / 2 * ‖y‖
Module: Mathlib.Analysis.Normed.Operator.Banach

Goal state before:
pp: case zero
𝕜 : Type u_1
𝕜' : Type u_2
inst✝¹⁰ : NontriviallyNormedField 𝕜
inst✝⁹ : NontriviallyNormedField 𝕜'
σ : 𝕜 →+* 𝕜'
E : Type u_3
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_4
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜' F
f : E →SL[σ] F
σ' : 𝕜' →+* 𝕜
inst✝⁴ : RingHomInvPair σ σ'
inst✝³ : RingHomIsometric σ
inst✝² : RingHomIsometric σ'
inst✝¹ : CompleteSpace F
inst✝ : CompleteSpace E
surj : Surjective ⇑f
C : ℝ
C0 : C ≥ 0
g : F → E
hg : ∀ (y : F), dist (f (g y)) y ≤ 1 / 2 * ‖y‖ ∧ ‖g y‖ ≤ C * ‖y‖
h : F → F := fun y ↦ y - f (g y)
hle : ∀ (y : F), ‖h y‖ ≤ 1 / 2 * ‖y‖
y : F
hnle : ∀ (n : ℕ), ‖h^[n] y‖ ≤ (1 / 2) ^ n * ‖y‖
u : ℕ → E := fun n ↦ g (h^[n] y)
ule : ∀ (n : ℕ), ‖u n‖ ≤ (1 / 2) ^ n * (C * ‖y‖)
sNu : Summable fun n ↦ ‖u n‖
su : Summable u
x : E := tsum u
x_ineq : ‖x‖ ≤ (2 * C + 1) * ‖y‖
⊢ f (∑ i ∈ Finset.range 0, u i) = y - h^[0] y

Tactic:
simp [f.map_zero]

Goal state after:
Module: Mathlib.Analysis.Normed.Lp.ProdLp

Goal state before:
pp: case inr
p : ℝ≥0∞
α : Type u_2
β : Type u_3
hp : Fact (1 ≤ p)
inst✝¹ : PseudoEMetricSpace α
inst✝ : PseudoEMetricSpace β
x y : WithLp p (α × β)
h : 1 ≤ p.toReal
⊢ edist x.fst y.fst ≤ edist x y ∧ edist x.snd y.snd ≤ edist x y

Tactic:
have cancel : p.toReal * (1 / p.toReal) = 1 := mul_div_cancel₀ 1 (zero_lt_one.trans_le h).ne'

Goal state after:
case inr
p : ℝ≥0∞
α : Type u_2
β : Type u_3
hp : Fact (1 ≤ p)
inst✝¹ : PseudoEMetricSpace α
inst✝ : PseudoEMetricSpace β
x y : WithLp p (α × β)
h : 1 ≤ p.toReal
cancel : p.toReal * (1 / p.toReal) = 1
⊢ edist x.fst y.fst ≤ edist x y ∧ edist x.snd y.snd ≤ edist x y
Module: Mathlib.Analysis.Normed.Lp.ProdLp

Goal state before:
pp: case top
α : Type u_2
β : Type u_3
inst✝¹ : SeminormedAddCommGroup α
inst✝ : SeminormedAddCommGroup β
x : α
hp : Fact (1 ≤ ∞)
⊢ ‖toLp ∞ (x, 0)‖₊ = ‖x‖₊

Tactic:
simp [prod_nnnorm_eq_sup]

Goal state after:
Module: Mathlib.Analysis.Normed.Lp.ProdLp

Goal state before:
pp: case top
α : Type u_2
β : Type u_3
inst✝¹ : SeminormedAddCommGroup α
inst✝ : SeminormedAddCommGroup β
y : β
hp : Fact (1 ≤ ∞)
⊢ ‖toLp ∞ (0, y)‖₊ = ‖y‖₊

Tactic:
simp [prod_nnnorm_eq_sup]

Goal state after:
Module: Mathlib.LinearAlgebra.UnitaryGroup

Goal state before:
pp: n : Type u
inst✝³ : DecidableEq n
inst✝² : Fintype n
α : Type v
inst✝¹ : CommRing α
inst✝ : StarRing α
A : Matrix n n α
hA : star A * A = 1
⊢ A * star A = 1

Tactic:
rwa [mul_eq_one_comm] at hA

Goal state after:
Module: Mathlib.Analysis.Normed.Lp.PiLp

Goal state before:
pp: case inr
p : ℝ≥0∞
ι : Type u_2
β : ι → Type u_4
inst✝² : Fact (1 ≤ p)
inst✝¹ : (i : ι) → PseudoEMetricSpace (β i)
inst✝ : Fintype ι
x y : PiLp p β
i : ι
h : 1 ≤ p.toReal
⊢ edist (x.ofLp i) (y.ofLp i) ≤ edist x y

Tactic:
have cancel : p.toReal * (1 / p.toReal) = 1 := mul_div_cancel₀ 1 (zero_lt_one.trans_le h).ne'

Goal state after:
case inr
p : ℝ≥0∞
ι : Type u_2
β : ι → Type u_4
inst✝² : Fact (1 ≤ p)
inst✝¹ : (i : ι) → PseudoEMetricSpace (β i)
inst✝ : Fintype ι
x y : PiLp p β
i : ι
h : 1 ≤ p.toReal
cancel : p.toReal * (1 / p.toReal) = 1
⊢ edist (x.ofLp i) (y.ofLp i) ≤ edist x y
Module: Mathlib.Analysis.Normed.Lp.PiLp

Goal state before:
pp: ι : Type u_2
β : ι → Type u_4
inst✝¹ : Fintype ι
inst✝ : (i : ι) → SeminormedAddCommGroup (β i)
x y : PiLp 1 β
⊢ ↑(nndist x y) = ↑(∑ i, nndist (x.ofLp i) (y.ofLp i))

Tactic:
push_cast; exact dist_eq_of_L1 _ _

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

Goal state before:
pp: case inl
a : ℝ
⊢ volume (eball a ∞) = 2 * ∞

Tactic:
Metric.eball_top,

Goal state after:
case inl
a : ℝ
⊢ volume univ = 2 * ∞
Module: Mathlib.Analysis.Normed.Lp.PiLp

Goal state before:
pp: case inr
p : ℝ≥0∞
𝕜 : Type u_1
ι : Type u_2
α : ι → Type u_3
β : ι → Type u_4
hp✝ : Fact (1 ≤ p)
inst✝⁴ : Fintype ι
inst✝³ : SeminormedRing 𝕜
inst✝² : (i : ι) → SeminormedAddCommGroup (β i)
inst✝¹ : (i : ι) → Module 𝕜 (β i)
inst✝ : ∀ (i : ι), NormSMulClass 𝕜 (β i)
c : 𝕜
f : PiLp p β
hp : 1 ≤ p.toReal
hp0 : 0 < p.toReal
hpt : p ≠ ∞
⊢ ∑ i, ‖(c • f).ofLp i‖₊ ^ p.toReal = ∑ i, ‖c‖₊ ^ p.toReal * ‖f.ofLp i‖₊ ^ p.toReal

Tactic:
simp_rw [← NNReal.mul_rpow, smul_apply, nnnorm_smul]

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

Goal state before:
pp: ι : Type u_1
inst✝ : Fintype ι
a : ι → ℝ
r : ℝ
hr : 0 < r
⊢ ofReal (2 * r) ^ Finset.univ.card = ofReal ((2 * r) ^ Fintype.card ι)

Tactic:
exact (ENNReal.ofReal_pow (mul_nonneg zero_le_two hr.le) _).symm

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

Goal state before:
pp: ι : Type u_1
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
D : ι → ℝ
h : (Matrix.diagonal D).det ≠ 0
s : ι → Set ℝ
hs : ∀ (i : ι), MeasurableSet (s i)
this : (⇑(toLin' (Matrix.diagonal D)) ⁻¹' univ.pi fun i ↦ s i) = univ.pi fun i ↦ (fun x ↦ D i * x) ⁻¹' s i
i : ι
A : D i ≠ 0
⊢ ofReal |D i| * volume ((fun x ↦ D i * x) ⁻¹' s i) = volume (s i)

Tactic:
rw [volume_preimage_mul_left A, ← mul_assoc, ← ENNReal.ofReal_mul (abs_nonneg _), ← abs_mul,
      mul_inv_cancel₀ A, abs_one, ENNReal.ofReal_one, one_mul]

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Lebesgue.EqHaar

Goal state before:
pp: ⊢ (interior (Icc 0 1)).Nonempty

Tactic:
interior_Icc,

Goal state after:
⊢ (Ioo 0 1).Nonempty
Module: Mathlib.MeasureTheory.Measure.Lebesgue.EqHaar

Goal state before:
pp: E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
inst✝¹ : FiniteDimensional ℝ E
μ : Measure E
inst✝ : μ.IsAddHaarMeasure
s : Submodule ℝ E
hs : s ≠ ⊤
x : E
hx : x ∉ s
c : ℝ
cpos : 0 < c
cone : c < 1
A : Bornology.IsBounded (range fun n ↦ c ^ n • x)
m n : ℕ
hmn : m ≠ n
⊢ ∀ ⦃a : E⦄, -(c ^ m • x) + a ∈ s → -(c ^ n • x) + a ∉ s

Tactic:
intro y

Goal state after:
E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
inst✝¹ : FiniteDimensional ℝ E
μ : Measure E
inst✝ : μ.IsAddHaarMeasure
s : Submodule ℝ E
hs : s ≠ ⊤
x : E
hx : x ∉ s
c : ℝ
cpos : 0 < c
cone : c < 1
A : Bornology.IsBounded (range fun n ↦ c ^ n • x)
m n : ℕ
hmn : m ≠ n
y : E
⊢ -(c ^ m • x) + y ∈ s → -(c ^ n • x) + y ∉ s
Module: Mathlib.Algebra.Module.ZLattice.Basic

Goal state before:
pp: ι : Type u_2
inst✝ : Finite ι
⊢ DiscreteTopology ↥(span ℤ (Set.range ⇑(Pi.basisFun ℝ ι)))

Tactic:
cases nonempty_fintype ι
  refine discreteTopology_iff_isOpen_singleton_zero.mpr ⟨Metric.ball 0 1, Metric.isOpen_ball, ?_⟩
  ext x
  rw [Set.mem_preimage, mem_ball_zero_iff, pi_norm_lt_iff zero_lt_one, Set.mem_singleton_iff]
  simp_rw [← coe_eq_zero, funext_iff, Pi.zero_apply, Real.norm_eq_abs]
  refine forall_congr' (fun i => ?_)
  rsuffices ⟨y, hy⟩ : ∃ (y : ℤ), (y : ℝ) = (x : ι → ℝ) i
  · rw [← hy, ← Int.cast_abs, ← Int.cast_one, Int.cast_lt, Int.abs_lt_one_iff, Int.cast_eq_zero]
  exact ((Pi.basisFun ℝ ι).mem_span_iff_repr_mem ℤ x).mp (SetLike.coe_mem x) i

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Lebesgue.EqHaar

Goal state before:
pp: E : Type u_1
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace ℝ E
inst✝⁴ : MeasurableSpace E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
μ : Measure E
inst✝¹ : μ.IsAddHaarMeasure
inst✝ : Nontrivial E
x : E
r : ℝ
hr : 0 ≤ r
⊢ μ (ball x r) = ENNReal.ofReal (r ^ finrank ℝ E) * μ (ball 0 1)

Tactic:
rw [← addHaar_ball_mul μ x hr, mul_one]

Goal state after:
Module: Mathlib.Analysis.BoxIntegral.Box.Basic

Goal state before:
pp: n : ℕ
I : Box (Fin (n + 1))
i : Fin (n + 1)
x : ℝ
hx : x ∈ Ioc (I.lower i) (I.upper i)
⊢ MapsTo (i.insertNth x) ↑(I.face i) ↑I

Tactic:
intro y

Goal state after:
n : ℕ
I : Box (Fin (n + 1))
i : Fin (n + 1)
x : ℝ
hx : x ∈ Ioc (I.lower i) (I.upper i)
y : Fin n → ℝ
⊢ y ∈ ↑(I.face i) → i.insertNth x y ∈ ↑I
Module: Mathlib.Algebra.Module.ZLattice.Basic

Goal state before:
pp: K : Type u_1
inst✝¹³ : NormedField K
inst✝¹² : LinearOrder K
inst✝¹¹ : IsStrictOrderedRing K
inst✝¹⁰ : HasSolidNorm K
inst✝⁹ : FloorRing K
E✝ : Type u_2
inst✝⁸ : NormedAddCommGroup E✝
inst✝⁷ : NormedSpace K E✝
inst✝⁶ : FiniteDimensional K E✝
inst✝⁵ : ProperSpace E✝
L✝ : Submodule ℤ E✝
inst✝⁴ : DiscreteTopology ↥L✝
E : Type u_3
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
inst✝¹ : FiniteDimensional ℝ E
L : Submodule ℤ E
inst✝ : DiscreteTopology ↥L
f : ↥(span ℝ ↑L) →ₗ[ℝ] E := (span ℝ ↑L).subtype
L₀ : Submodule ℤ ↥(span ℝ ↑L) := comap (↑ℤ f) L
⊢ ⇑(↑ℤ f) '' ↑L₀ = ↑L

Tactic:
← Submodule.map_coe (f.restrictScalars ℤ),

Goal state after:
K : Type u_1
inst✝¹³ : NormedField K
inst✝¹² : LinearOrder K
inst✝¹¹ : IsStrictOrderedRing K
inst✝¹⁰ : HasSolidNorm K
inst✝⁹ : FloorRing K
E✝ : Type u_2
inst✝⁸ : NormedAddCommGroup E✝
inst✝⁷ : NormedSpace K E✝
inst✝⁶ : FiniteDimensional K E✝
inst✝⁵ : ProperSpace E✝
L✝ : Submodule ℤ E✝
inst✝⁴ : DiscreteTopology ↥L✝
E : Type u_3
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
inst✝¹ : FiniteDimensional ℝ E
L : Submodule ℤ E
inst✝ : DiscreteTopology ↥L
f : ↥(span ℝ ↑L) →ₗ[ℝ] E := (span ℝ ↑L).subtype
L₀ : Submodule ℤ ↥(span ℝ ↑L) := comap (↑ℤ f) L
⊢ ↑(Submodule.map (↑ℤ f) L₀) = ↑L
Module: Mathlib.MeasureTheory.Measure.Lebesgue.EqHaar

Goal state before:
pp: E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
inst✝¹ : FiniteDimensional ℝ E
μ : Measure E
inst✝ : μ.IsAddHaarMeasure
s : Set E
x : E
h : Tendsto (fun r ↦ μ (s ∩ closedBall x r) / μ (closedBall x r)) (𝓝[>] 0) (𝓝 0)
t u : Set E
h'u : μ u ≠ 0
t_bound : t ⊆ closedBall 0 1
A : Tendsto (fun r ↦ μ (s ∩ ({x} + r • t)) / μ (closedBall x r)) (𝓝[>] 0) (𝓝 0)
B : Tendsto (fun r ↦ μ (closedBall x r) / μ ({x} + r • u)) (𝓝[>] 0) (𝓝 (μ (closedBall x 1) / μ ({x} + u)))
C : Tendsto (fun r ↦ μ (s ∩ ({x} + r • t)) / μ (closedBall x r) * (μ (closedBall x r) / μ ({x} + r • u))) (𝓝[>] 0) (𝓝 0)
r : ℝ
rpos : 0 < r
⊢ μ (closedBall x r) * (μ (closedBall x r))⁻¹ * (μ (s ∩ ({x} + r • t)) / μ ({x} + r • u)) =
    μ (s ∩ ({x} + r • t)) / μ ({x} + r • u)

Tactic:
rw [ENNReal.mul_inv_cancel (measure_closedBall_pos μ x rpos).ne'
          measure_closedBall_lt_top.ne,
        one_mul]

Goal state after:
Module: Mathlib.Analysis.BoxIntegral.Partition.Basic

Goal state before:
pp: case inl
ι : Type u_1
I : Box ι
π : Prepartition I
x : ι → ℝ
J₁ : Box ι
h₁ : J₁ ∈ π
hx₁ : x ∈ Box.Icc J₁
J₂ : Box ι
h₂ : J₂ ∈ π
hx₂ : x ∈ Box.Icc J₂
i : ι
H : ∀ (x_1 : ι), J₁.lower x_1 = x x_1 ↔ J₂.lower x_1 = x x_1
hi₁ : J₁.lower i = x i
hi₂ : J₂.lower i = x i
H₁ : x i < J₁.upper i
H₂ : x i < J₂.upper i
⊢ (Set.Ioc (max (x i) (J₂.lower i)) (min (J₁.upper i) (J₂.upper i))).Nonempty

Tactic:
hi₂,

Goal state after:
case inl
ι : Type u_1
I : Box ι
π : Prepartition I
x : ι → ℝ
J₁ : Box ι
h₁ : J₁ ∈ π
hx₁ : x ∈ Box.Icc J₁
J₂ : Box ι
h₂ : J₂ ∈ π
hx₂ : x ∈ Box.Icc J₂
i : ι
H : ∀ (x_1 : ι), J₁.lower x_1 = x x_1 ↔ J₂.lower x_1 = x x_1
hi₁ : J₁.lower i = x i
hi₂ : J₂.lower i = x i
H₁ : x i < J₁.upper i
H₂ : x i < J₂.upper i
⊢ (Set.Ioc (max (x i) (x i)) (min (J₁.upper i) (J₂.upper i))).Nonempty