mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
hA : ediam A ≤ ↑ε
⊢ coveringNumber ε A ≤ 1

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
x : X
⊢ {x}.Nonempty

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
x : X
⊢ ediam {x} ≤ ↑ε

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.GromovHausdorffRealized

Goal state before:
pp: X : Type u
Y : Type v
inst✝¹ : MetricSpace X
inst✝ : MetricSpace Y
f : ProdSpaceFun X Y
x y z t : X ⊕ Y
fA : f ∈ candidates X Y
⊢ f (x, y) - f (z, t) ≤ f (x, z) + f (z, t) + f (t, y) - f (z, t)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Kuratowski

Goal state before:
pp: α : Type u
inst✝ : MetricSpace α
x : ℕ → α
H : DenseRange x
⊢ Isometry (embeddingOfSubset x)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
x : X
⊢ {x}.encard = 1

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
x : X
⊢ {x} ⊆ {x}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.GromovHausdorffRealized

Goal state before:
pp: X : Type u
Y : Type v
inst✝¹ : MetricSpace X
inst✝ : MetricSpace Y
f : ProdSpaceFun X Y
x y z t : X ⊕ Y
fA : f ∈ candidates X Y
⊢ f (x, z) + f (z, t) + f (t, y) - f (z, t) = f (x, z) + f (t, y)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
x : X
⊢ IsSeparated ↑ε {x}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
x : X
⊢ 1 ≤ {x}.encard

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Kuratowski

Goal state before:
pp: α : Type u
inst✝¹ : MetricSpace α
inst✝ : SeparableSpace α
⊢ ∃ f, Isometry f

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.GromovHausdorffRealized

Goal state before:
pp: X : Type u
Y : Type v
inst✝¹ : MetricSpace X
inst✝ : MetricSpace Y
f : ProdSpaceFun X Y
x y z t : X ⊕ Y
fA : f ∈ candidates X Y
⊢ f (x, z) + f (t, y) ≤ ↑(maxVar X Y) * dist x z + ↑(maxVar X Y) * dist t y

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Kuratowski

Goal state before:
pp: α : Type u
inst✝ : PseudoMetricSpace α
ι : Type u_1
f : α → ↥(lp (fun x ↦ ℝ) ∞)
K : ℝ≥0
g : ι → α → ℝ
hgl : ∀ (i : ι), LipschitzWith K (g i)
hfl : ∀ (i : ι), LipschitzOnWith K (fun a ↦ ↑(f a) i) ∅
hgeq : ∀ (i : ι), EqOn (fun x ↦ ↑(f x) i) (g i) ∅
⊢ EqOn f 0 ∅

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.GromovHausdorffRealized

Goal state before:
pp: X : Type u
Y : Type v
inst✝¹ : MetricSpace X
inst✝ : MetricSpace Y
f : ProdSpaceFun X Y
x y z t : X ⊕ Y
fA : f ∈ candidates X Y
⊢ ↑(maxVar X Y) * dist x z + ↑(maxVar X Y) * dist t y ≤
    ↑(maxVar X Y) * max (dist x z) (dist t y) + ↑(maxVar X Y) * max (dist x z) (dist t y)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Kuratowski

Goal state before:
pp: α : Type u
inst✝ : PseudoMetricSpace α
s : Set α
ι : Type u_1
f : α → ↥(lp (fun x ↦ ℝ) ∞)
K : ℝ≥0
hfl : ∀ (i : ι), LipschitzOnWith K (fun a ↦ ↑(f a) i) s
g : ι → α → ℝ
hgl : ∀ (i : ι), LipschitzWith K (g i)
hgeq : ∀ (i : ι), EqOn (fun x ↦ ↑(f x) i) (g i) s
a₀ : α
ha₀_in_s : a₀ ∈ s
⊢ ∀ (a : α), Memℓp (swap g a) ∞

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s✝ : Set α
inst✝ : CompleteSpace α
B : ℕ → ℝ≥0∞ := fun n ↦ 2⁻¹ ^ n
B_pos : ∀ (n : ℕ), 0 < B n
B_ne_top : ∀ (n : ℕ), B n ≠ ∞
s : ℕ → Closeds α
hs : ∀ (N n m : ℕ), N ≤ n → N ≤ m → edist (s n) (s m) < B N
t0 : Set α := ⋂ n, closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
t : Closeds α := { carrier := t0, isClosed' := ⋯ }
n : ℕ
x : α
hx : x ∈ s n
⊢ ∃ z, ↑(z 0) = x ∧ ∀ (k : ℕ), edist ↑(z k) ↑(z (k + 1)) ≤ B n / 2 ^ k

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.GromovHausdorffRealized

Goal state before:
pp: X : Type u
Y : Type v
inst✝¹ : MetricSpace X
inst✝ : MetricSpace Y
f : ProdSpaceFun X Y
x y z t : X ⊕ Y
fA : f ∈ candidates X Y
⊢ ↑(maxVar X Y) * max (dist x z) (dist t y) + ↑(maxVar X Y) * max (dist x z) (dist t y) =
    2 * ↑(maxVar X Y) * max (dist x z) (dist y t)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.GromovHausdorffRealized

Goal state before:
pp: X : Type u
Y : Type v
inst✝¹ : MetricSpace X
inst✝ : MetricSpace Y
f : ProdSpaceFun X Y
fA : f ∈ candidates X Y
⊢ LipschitzWith (2 * maxVar X Y) f

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Kuratowski

Goal state before:
pp: α : Type u
inst✝ : PseudoMetricSpace α
s : Set α
ι : Type u_1
f : α → ↥(lp (fun x ↦ ℝ) ∞)
K : ℝ≥0
hfl : LipschitzOnWith K f s
⊢ ∃ g, LipschitzWith K g ∧ EqOn f g s

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s✝ : Set α
inst✝ : CompleteSpace α
B : ℕ → ℝ≥0∞ := fun n ↦ 2⁻¹ ^ n
B_pos : ∀ (n : ℕ), 0 < B n
B_ne_top : ∀ (n : ℕ), B n ≠ ∞
s : ℕ → Closeds α
hs : ∀ (N n m : ℕ), N ≤ n → N ≤ m → edist (s n) (s m) < B N
t0 : Set α := ⋂ n, closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
t : Closeds α := { carrier := t0, isClosed' := ⋯ }
n : ℕ
x : α
hx : x ∈ s n
z : (l : ℕ) → ↥(s (n + l))
hz₀ : ↑(z 0) = x
hz : ∀ (k : ℕ), edist ↑(z k) ↑(z (k + 1)) ≤ B n / 2 ^ k
this : CauchySeq fun k ↦ ↑(z k)
y : α
y_lim : Tendsto (fun k ↦ ↑(z k)) atTop (𝓝 y)
k m : ℕ
hm : k ≤ m
⊢ n + m ≥ k

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : coveringNumber ε A ≠ ⊤
⊢ ∃ C ⊆ A, C.Finite ∧ IsCover ε A C ∧ C.encard = coveringNumber ε A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
⊢ minimalCover ε A ⊆ A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
⊢ (minimalCover ε A).Finite

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : coveringNumber ε A ≠ ⊤
⊢ IsCover ε A (minimalCover ε A)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : coveringNumber ε A ≠ ⊤
⊢ (minimalCover ε A).encard = coveringNumber ε A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.GromovHausdorffRealized

Goal state before:
pp: X : Type u
Y : Type v
inst✝¹ : MetricSpace X
inst✝ : MetricSpace Y
I1 : ∀ (x y : X), IsClosed {f | f (inl x, inl y) = dist x y}
I2 : ∀ (x y : Y), IsClosed {f | f (inr x, inr y) = dist x y}
I3 : ∀ (x y : X ⊕ Y), IsClosed {f | f (x, y) = f (y, x)}
I4 : ∀ (x y z : X ⊕ Y), IsClosed {f | f (x, z) ≤ f (x, y) + f (y, z)}
I5 : ∀ (x : X ⊕ Y), IsClosed {f | f (x, x) = 0}
I6 : ∀ (x y : X ⊕ Y), IsClosed {f | f (x, y) ≤ ↑(maxVar X Y)}
⊢ candidatesB X Y =
    (((((⋂ x, ⋂ y, {f | f (inl x, inl y) = dist x y}) ∩ ⋂ x, ⋂ y, {f | f (inr x, inr y) = dist x y}) ∩
            ⋂ x, ⋂ y, {f | f (x, y) = f (y, x)}) ∩
          ⋂ x, ⋂ y, ⋂ z, {f | f (x, z) ≤ f (x, y) + f (y, z)}) ∩
        ⋂ x, {f | f (x, x) = 0}) ∩
      ⋂ x, ⋂ y, {f | f (x, y) ≤ ↑(maxVar X Y)}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : packingNumber ε A ≠ ⊤
a : X
ha : a ∈ A
⊢ {a} ⊆ A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : packingNumber ε A ≠ ⊤
a : X
ha : a ∈ A
⊢ IsSeparated ↑ε {a}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : packingNumber ε A ≠ ⊤
hA : A.Nonempty
⊢ Nonempty { s // s ⊆ A ∧ IsSeparated (↑ε) s }

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s✝ : Set α
inst✝ : CompleteSpace α
B : ℕ → ℝ≥0∞ := fun n ↦ 2⁻¹ ^ n
B_pos : ∀ (n : ℕ), 0 < B n
B_ne_top : ∀ (n : ℕ), B n ≠ ∞
s : ℕ → Closeds α
hs : ∀ (N n m : ℕ), N ≤ n → N ≤ m → edist (s n) (s m) < B N
t0 : Set α := ⋂ n, closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
t : Closeds α := { carrier := t0, isClosed' := ⋯ }
n : ℕ
x : α
hx : x ∈ s n
z : (l : ℕ) → ↥(s (n + l))
hz₀ : ↑(z 0) = x
hz : ∀ (k : ℕ), edist ↑(z k) ↑(z (k + 1)) ≤ B n / 2 ^ k
this : CauchySeq fun k ↦ ↑(z k)
y : α
y_lim : Tendsto (fun k ↦ ↑(z k)) atTop (𝓝 y)
k : ℕ
⊢ ∀ᶠ (x : ℕ) in atTop, ↑(z x) ∈ ⋃ m, ⋃ (_ : m ≥ k), ↑(s m)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s✝ : Set α
inst✝ : CompleteSpace α
B : ℕ → ℝ≥0∞ := fun n ↦ 2⁻¹ ^ n
B_pos : ∀ (n : ℕ), 0 < B n
B_ne_top : ∀ (n : ℕ), B n ≠ ∞
s : ℕ → Closeds α
hs : ∀ (N n m : ℕ), N ≤ n → N ≤ m → edist (s n) (s m) < B N
t0 : Set α := ⋂ n, closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
t : Closeds α := { carrier := t0, isClosed' := ⋯ }
⊢ ∀ (n : ℕ), ∀ x ∈ s n, ∃ y ∈ t0, edist x y ≤ 2 * B n

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s✝ : Set α
inst✝ : CompleteSpace α
B : ℕ → ℝ≥0∞ := fun n ↦ 2⁻¹ ^ n
B_pos : ∀ (n : ℕ), 0 < B n
B_ne_top : ∀ (n : ℕ), B n ≠ ∞
s : ℕ → Closeds α
hs : ∀ (N n m : ℕ), N ≤ n → N ≤ m → edist (s n) (s m) < B N
t0 : Set α := ⋂ n, closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
t : Closeds α := { carrier := t0, isClosed' := ⋯ }
I1 : ∀ (n : ℕ), ∀ x ∈ s n, ∃ y ∈ t0, edist x y ≤ 2 * B n
n : ℕ
x : α
xt0 : x ∈ t0
⊢ x ∈ closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : packingNumber ε A ≠ ⊤
⊢ ∃ C ⊆ A, C.Finite ∧ IsSeparated (↑ε) C ∧ C.encard = packingNumber ε A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
⊢ maximalSeparatedSet ε A ⊆ A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
⊢ IsSeparated (↑ε) (maximalSeparatedSet ε A)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : packingNumber ε A ≠ ⊤
⊢ (maximalSeparatedSet ε A).encard = packingNumber ε A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A C : Set X
ε : ℝ≥0
h_subset : C ⊆ A
h_sep : IsSeparated (↑ε) C
h : packingNumber ε A ≠ ⊤
⊢ C.encard ≤ (maximalSeparatedSet ε A).encard

Tactic:
encard_maximalSeparatedSet h

Goal state after:
X : Type u_1
inst✝ : PseudoEMetricSpace X
A C : Set X
ε : ℝ≥0
h_subset : C ⊆ A
h_sep : IsSeparated (↑ε) C
h : packingNumber ε A ≠ ⊤
⊢ C.encard ≤ packingNumber ε A
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A C : Set X
ε : ℝ≥0
h_subset : C ⊆ A
h_sep : IsSeparated (↑ε) C
h : packingNumber ε A ≠ ⊤
⊢ C.encard ≤ C.encard

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A C : Set X
ε : ℝ≥0
h_subset : C ⊆ A
h_sep : IsSeparated (↑ε) C
h : packingNumber ε A ≠ ⊤
⊢ C.encard ≤ (maximalSeparatedSet ε A).encard

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : packingNumber ε A ≠ ⊤
x : X
hxA : x ∈ A
h_dist : ∀ y ∈ maximalSeparatedSet ε A, (x, y) ∉ {x | edist x.1 x.2 ≤ ↑ε}
C : Set X := {x} ∪ maximalSeparatedSet ε A
⊢ x ∉ maximalSeparatedSet ε A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : packingNumber ε A ≠ ⊤
x : X
hxA : x ∈ A
h_dist : ∀ y ∈ maximalSeparatedSet ε A, (x, y) ∉ {x | edist x.1 x.2 ≤ ↑ε}
C : Set X := {x} ∪ maximalSeparatedSet ε A
hx_not_mem : x ∉ maximalSeparatedSet ε A
this : C ⊆ A ∧ IsSeparated (↑ε) C
⊢ False

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s✝ : Set α
inst✝ : CompleteSpace α
B : ℕ → ℝ≥0∞ := fun n ↦ 2⁻¹ ^ n
B_pos : ∀ (n : ℕ), 0 < B n
B_ne_top : ∀ (n : ℕ), B n ≠ ∞
s : ℕ → Closeds α
hs : ∀ (N n m : ℕ), N ≤ n → N ≤ m → edist (s n) (s m) < B N
t0 : Set α := ⋂ n, closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
t : Closeds α := { carrier := t0, isClosed' := ⋯ }
I1 : ∀ (n : ℕ), ∀ x ∈ s n, ∃ y ∈ t0, edist x y ≤ 2 * B n
n : ℕ
x : α
xt0 : x ∈ t0
this✝ : x ∈ closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
z : α
Dxz : edist x z < B n
m : ℕ
m_ge_n : m ≥ n
hm : z ∈ ↑(s m)
this : hausdorffEDist ↑(s m) ↑(s n) < B n
y : α
hy : y ∈ ↑(s n)
Dzy : edist z y < B n
⊢ edist x z + edist z y ≤ B n + B n

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s✝ : Set α
inst✝ : CompleteSpace α
B : ℕ → ℝ≥0∞ := fun n ↦ 2⁻¹ ^ n
B_pos : ∀ (n : ℕ), 0 < B n
B_ne_top : ∀ (n : ℕ), B n ≠ ∞
s : ℕ → Closeds α
hs : ∀ (N n m : ℕ), N ≤ n → N ≤ m → edist (s n) (s m) < B N
t0 : Set α := ⋂ n, closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
t : Closeds α := { carrier := t0, isClosed' := ⋯ }
I1 : ∀ (n : ℕ), ∀ x ∈ s n, ∃ y ∈ t0, edist x y ≤ 2 * B n
⊢ ∀ (n : ℕ), ∀ x ∈ t0, ∃ y ∈ s n, edist x y ≤ 2 * B n

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : packingNumber ε A ≠ ⊤
x : X
hxA : x ∈ A
h_dist : ∀ y ∈ maximalSeparatedSet ε A, (x, y) ∉ {x | edist x.1 x.2 ≤ ↑ε}
C : Set X := {x} ∪ maximalSeparatedSet ε A
hx_not_mem : x ∉ maximalSeparatedSet ε A
⊢ ∀ y ∈ maximalSeparatedSet ε A, ↑ε < edist x y

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : packingNumber ε A ≠ ⊤
⊢ IsCover ε A (maximalSeparatedSet ε A)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
A C : Set X
hC_cover : IsCover ε A C
D : Set X
hD_subset : D ⊆ A
hD_separated : IsSeparated (2 * ↑ε) D
f : ↑D → ↑C := fun x ↦ ⟨⋯.choose, ⋯⟩
⊢ D.encard ≤ C.encard

Tactic:
have hf' (x : D) : edist x.1 (f x) ≤ ε := (hC_cover (hD_subset x.2)).choose_spec.2

Goal state after:
X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
A C : Set X
hC_cover : IsCover ε A C
D : Set X
hD_subset : D ⊆ A
hD_separated : IsSeparated (2 * ↑ε) D
f : ↑D → ↑C := fun x ↦ ⟨⋯.choose, ⋯⟩
hf' : ∀ (x : ↑D), edist ↑x ↑(f x) ≤ ↑ε
⊢ D.encard ≤ C.encard
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s✝ : Set α
inst✝ : CompleteSpace α
B : ℕ → ℝ≥0∞ := fun n ↦ 2⁻¹ ^ n
B_pos : ∀ (n : ℕ), 0 < B n
B_ne_top : ∀ (n : ℕ), B n ≠ ∞
s : ℕ → Closeds α
hs : ∀ (N n m : ℕ), N ≤ n → N ≤ m → edist (s n) (s m) < B N
t0 : Set α := ⋂ n, closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
t : Closeds α := { carrier := t0, isClosed' := ⋯ }
I1 : ∀ (n : ℕ), ∀ x ∈ s n, ∃ y ∈ t0, edist x y ≤ 2 * B n
I2 : ∀ (n : ℕ), ∀ x ∈ t0, ∃ y ∈ s n, edist x y ≤ 2 * B n
main : ∀ (n : ℕ), edist (s n) t ≤ 2 * B n
ε : ℝ≥0∞
εpos : ε > 0
⊢ 2⁻¹ < 1

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s✝ : Set α
inst✝ : CompleteSpace α
B : ℕ → ℝ≥0∞ := fun n ↦ 2⁻¹ ^ n
B_pos : ∀ (n : ℕ), 0 < B n
B_ne_top : ∀ (n : ℕ), B n ≠ ∞
s : ℕ → Closeds α
hs : ∀ (N n m : ℕ), N ≤ n → N ≤ m → edist (s n) (s m) < B N
t0 : Set α := ⋂ n, closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ m, ⋃ (_ : m ≥ n), ↑(s m))
t : Closeds α := { carrier := t0, isClosed' := ⋯ }
I1 : ∀ (n : ℕ), ∀ x ∈ s n, ∃ y ∈ t0, edist x y ≤ 2 * B n
I2 : ∀ (n : ℕ), ∀ x ∈ t0, ∃ y ∈ s n, edist x y ≤ 2 * B n
main : ∀ (n : ℕ), edist (s n) t ≤ 2 * B n
ε : ℝ≥0∞
εpos : ε > 0
⊢ 2 ≠ ∞

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
A C : Set X
hC_cover : IsCover ε A C
D : Set X
hD_subset : D ⊆ A
hD_separated : IsSeparated (2 * ↑ε) D
f : ↑D → ↑C := fun x ↦ ⟨⋯.choose, ⋯⟩
hf' : ∀ (x : ↑D), edist ↑x ↑(f x) ≤ ↑ε
x y : ↑D
hxy : f x = f y
⊢ edist ↑x ↑(f x) + edist ↑(f x) ↑y ≤ 2 * ↑ε

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
A : Set X
⊢ packingNumber (2 * ε) A ≤ externalCoveringNumber ε A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝² : EMetricSpace α
inst✝¹ : EMetricSpace β
s : Set α
inst✝ : CompleteSpace α
⊢ CompleteSpace (Closeds α)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝¹ : EMetricSpace α
inst✝ : EMetricSpace β
s : Set α
⊢ uniformity (Compacts α) = uniformity (Compacts α)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
A : Set X
⊢ coveringNumber ε A ≤ packingNumber ε A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝¹ : EMetricSpace α
inst✝ : EMetricSpace β
s✝ : Set α
s t : Compacts α
h : edist s t = 0
⊢ ↑s = ↑t

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝¹ : EMetricSpace α
inst✝ : EMetricSpace β
s : Set α
⊢ uniformity (NonemptyCompacts α) = uniformity (NonemptyCompacts α)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝¹ : EMetricSpace α
inst✝ : EMetricSpace β
s✝ : Set α
s t : NonemptyCompacts α
h : edist s t = 0
⊢ ↑s = ↑t

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
ε : ℝ≥0
A : Set X
⊢ coveringNumber (2 * ε) A ≤ externalCoveringNumber ε A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
inst✝ : MetricSpace α
x : α
s t : NonemptyCompacts α
⊢ infDist x ↑s ≤ infDist x ↑t + dist s t

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A B : Set X
ε : ℝ≥0
h : A ⊆ B
⊢ packingNumber ε A = packingNumber (2 * (ε / 2)) A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.Closeds

Goal state before:
pp: α : Type u_1
inst✝ : MetricSpace α
⊢ LipschitzWith 2 fun p ↦ infDist p.1 ↑p.2

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffAlexandroff

Goal state before:
pp: ⊢ 1 < 2

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffAlexandroff

Goal state before:
pp: ⊢ Function.Surjective fromBinary

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffAlexandroff

Goal state before:
pp: x✝ : ℕ
⊢ Continuous fun a ↦ cantorSpaceHomeomorphNatToCantorSpace a x✝

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffAlexandroff

Goal state before:
pp: X : Set (ℕ → Bool)
h_closed : IsClosed X
h_nonempty : X.Nonempty
⊢ ∃ f, Continuous f ∧ Set.range f = X

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffAlexandroff

Goal state before:
pp: X : Type u_1
inst✝² : Nonempty X
inst✝¹ : MetricSpace X
inst✝ : CompactSpace X
this : TopologicalSpace.SeparableSpace X := TopologicalSpace.SecondCountableTopology.to_separableSpace
emb : X → ℕ → ↑unitInterval
h_emb : Topology.IsEmbedding emb
KH : Set (ℕ → ↑unitInterval) := Set.range emb
g : X ≃ₜ ↑KH := h_emb.toHomeomorph
KC : Set (ℕ → Bool) := cantorToHilbert ⁻¹' KH
hKC_closed : IsClosed KC
f : (ℕ → Bool) → ℕ → Bool
hf_continuous : Continuous f
hf_surjective : Set.range f = KC
⊢ ∀ (a : ℕ → Bool), f a ∈ KC

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffAlexandroff

Goal state before:
pp: X : Type u_1
inst✝² : Nonempty X
inst✝¹ : MetricSpace X
inst✝ : CompactSpace X
this : TopologicalSpace.SeparableSpace X := TopologicalSpace.SecondCountableTopology.to_separableSpace
emb : X → ℕ → ↑unitInterval
h_emb : Topology.IsEmbedding emb
KH : Set (ℕ → ↑unitInterval) := Set.range emb
g : X ≃ₜ ↑KH := h_emb.toHomeomorph
KC : Set (ℕ → Bool) := cantorToHilbert ⁻¹' KH
hKC_closed : IsClosed KC
f : (ℕ → Bool) → ℕ → Bool
hf_continuous : Continuous f
hf_surjective : Set.range f = KC
f' : (ℕ → Bool) → ↑KC := Subtype.coind f ⋯
⊢ Set.SurjOn f Set.univ KC

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffAlexandroff

Goal state before:
pp: X : Type u_1
inst✝² : Nonempty X
inst✝¹ : MetricSpace X
inst✝ : CompactSpace X
this : TopologicalSpace.SeparableSpace X := TopologicalSpace.SecondCountableTopology.to_separableSpace
emb : X → ℕ → ↑unitInterval
h_emb : Topology.IsEmbedding emb
KH : Set (ℕ → ↑unitInterval) := Set.range emb
g : X ≃ₜ ↑KH := h_emb.toHomeomorph
KC : Set (ℕ → Bool) := cantorToHilbert ⁻¹' KH
hKC_closed : IsClosed KC
f : (ℕ → Bool) → ℕ → Bool
hf_continuous : Continuous f
hf_surjective : Set.range f = KC
f' : (ℕ → Bool) → ↑KC := Subtype.coind f ⋯
hf'_surjective : Function.Surjective f'
h : ↑KC → ↑KH := KH.restrictPreimage cantorToHilbert
hh_continuous : Continuous h
hh_surjective : Function.Surjective h
⊢ Continuous (⇑g.symm ∘ h ∘ f')

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.HausdorffAlexandroff

Goal state before:
pp: X : Type u_1
inst✝² : Nonempty X
inst✝¹ : MetricSpace X
inst✝ : CompactSpace X
⊢ ∃ f, Continuous f ∧ Function.Surjective f

Tactic:
by

Goal state after:
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : PseudoEMetricSpace X
inst✝ : PseudoEMetricSpace Y
A : Set X
ε : ℝ≥0
f : X → Y
hf : Isometry f
hf_inj : InjOn f A
C : Set Y
hC_subset : C ⊆ f '' A
hC_cover : IsCover ε (f '' A) C
x : ↑C
⊢ ∃ y ∈ A, f y = ↑x

Tactic:
by

Goal state after: