Theorem: has_unit_speed_naturalParameterization
File: Mathlib/Analysis/ConstantSpeed.lean

tactic: dsimp only [HasUnitSpeedOn]
state_before: α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
⊢ HasUnitSpeedOn (naturalParameterization f s a) (variationOnFromTo f s a '' s)
state_after: α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
⊢ HasConstantSpeedOnWith (naturalParameterization f s a) (variationOnFromTo f s a '' s) 1

tactic: rw [hasConstantSpeedOnWith_iff_ordered]
state_before: α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
⊢ HasConstantSpeedOnWith (naturalParameterization f s a) (variationOnFromTo f s a '' s) 1
state_after: α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
⊢ ∀ ⦃x : ℝ⦄,
    x ∈ variationOnFromTo f s a '' s →
      ∀ ⦃y : ℝ⦄,
        y ∈ variationOnFromTo f s a '' s →
          x ≤ y →
            eVariationOn (naturalParameterization f s a) (variationOnFromTo f s a '' s ∩ Icc x y) =
              ENNReal.ofReal (↑1 * (y - x))

tactic: rintro _ ⟨b, bs, rfl⟩ _ ⟨c, cs, rfl⟩ h
state_before: α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
⊢ ∀ ⦃x : ℝ⦄,
    x ∈ variationOnFromTo f s a '' s →
      ∀ ⦃y : ℝ⦄,
        y ∈ variationOnFromTo f s a '' s →
          x ≤ y →
            eVariationOn (naturalParameterization f s a) (variationOnFromTo f s a '' s ∩ Icc x y) =
              ENNReal.ofReal (↑1 * (y - x))
state_after: case intro.intro.intro.intro
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
⊢ eVariationOn (naturalParameterization f s a)
      (variationOnFromTo f s a '' s ∩ Icc (variationOnFromTo f s a b) (variationOnFromTo f s a c)) =
    ENNReal.ofReal (↑1 * (variationOnFromTo f s a c - variationOnFromTo f s a b))

tactic: rcases le_total c b with (cb | bc)
state_before: case intro.intro.intro.intro
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
⊢ eVariationOn (naturalParameterization f s a)
      (variationOnFromTo f s a '' s ∩ Icc (variationOnFromTo f s a b) (variationOnFromTo f s a c)) =
    ENNReal.ofReal (↑1 * (variationOnFromTo f s a c - variationOnFromTo f s a b))
state_after: case intro.intro.intro.intro.inl
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
cb : c ≤ b
⊢ eVariationOn (naturalParameterization f s a)
      (variationOnFromTo f s a '' s ∩ Icc (variationOnFromTo f s a b) (variationOnFromTo f s a c)) =
    ENNReal.ofReal (↑1 * (variationOnFromTo f s a c - variationOnFromTo f s a b))

case intro.intro.intro.intro.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ eVariationOn (naturalParameterization f s a)
      (variationOnFromTo f s a '' s ∩ Icc (variationOnFromTo f s a b) (variationOnFromTo f s a c)) =
    ENNReal.ofReal (↑1 * (variationOnFromTo f s a c - variationOnFromTo f s a b))

tactic: rw [NNReal.coe_one, one_mul, le_antisymm h (variationOnFromTo.monotoneOn hf as cs bs cb),
  sub_self, ENNReal.ofReal_zero, Icc_self, eVariationOn.subsingleton]
state_before: case intro.intro.intro.intro.inl
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
cb : c ≤ b
⊢ eVariationOn (naturalParameterization f s a)
      (variationOnFromTo f s a '' s ∩ Icc (variationOnFromTo f s a b) (variationOnFromTo f s a c)) =
    ENNReal.ofReal (↑1 * (variationOnFromTo f s a c - variationOnFromTo f s a b))
state_after: case intro.intro.intro.intro.inl.hs
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
cb : c ≤ b
⊢ (variationOnFromTo f s a '' s ∩ {variationOnFromTo f s a c}).Subsingleton

tactic: exact fun x hx y hy => hx.2.trans hy.2.symm
state_before: case intro.intro.intro.intro.inl.hs
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
cb : c ≤ b
⊢ (variationOnFromTo f s a '' s ∩ {variationOnFromTo f s a c}).Subsingleton
state_after: no goals

tactic: rw [NNReal.coe_one, one_mul, sub_eq_add_neg, variationOnFromTo.eq_neg_swap, neg_neg, add_comm,
  variationOnFromTo.add hf bs as cs, ← variationOnFromTo.eq_neg_swap f]
state_before: case intro.intro.intro.intro.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ eVariationOn (naturalParameterization f s a)
      (variationOnFromTo f s a '' s ∩ Icc (variationOnFromTo f s a b) (variationOnFromTo f s a c)) =
    ENNReal.ofReal (↑1 * (variationOnFromTo f s a c - variationOnFromTo f s a b))
state_after: case intro.intro.intro.intro.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ eVariationOn (naturalParameterization f s a)
      (variationOnFromTo f s a '' s ∩ Icc (variationOnFromTo f s a b) (variationOnFromTo f s a c)) =
    ENNReal.ofReal (variationOnFromTo f s b c)

tactic: rw [←
  eVariationOn.comp_inter_Icc_eq_of_monotoneOn (naturalParameterization f s a) _
    (variationOnFromTo.monotoneOn hf as) bs cs]
state_before: case intro.intro.intro.intro.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ eVariationOn (naturalParameterization f s a)
      (variationOnFromTo f s a '' s ∩ Icc (variationOnFromTo f s a b) (variationOnFromTo f s a c)) =
    ENNReal.ofReal (variationOnFromTo f s b c)
state_after: case intro.intro.intro.intro.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ eVariationOn (naturalParameterization f s a ∘ variationOnFromTo f s a) (s ∩ Icc b c) =
    ENNReal.ofReal (variationOnFromTo f s b c)

tactic: rw [@eVariationOn.eq_of_edist_zero_on _ _ _ _ _ f]
state_before: case intro.intro.intro.intro.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ eVariationOn (naturalParameterization f s a ∘ variationOnFromTo f s a) (s ∩ Icc b c) =
    ENNReal.ofReal (variationOnFromTo f s b c)
state_after: case intro.intro.intro.intro.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ eVariationOn f (s ∩ Icc b c) = ENNReal.ofReal (variationOnFromTo f s b c)

case intro.intro.intro.intro.inr.h
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ ∀ ⦃x : α⦄, x ∈ s ∩ Icc b c → edist ((naturalParameterization f s a ∘ variationOnFromTo f s a) x) (f x) = 0

tactic: rw [variationOnFromTo.eq_of_le _ _ bc, ENNReal.ofReal_toReal (hf b c bs cs)]
state_before: case intro.intro.intro.intro.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ eVariationOn f (s ∩ Icc b c) = ENNReal.ofReal (variationOnFromTo f s b c)
state_after: no goals

tactic: rintro x ⟨xs, _, _⟩
state_before: case intro.intro.intro.intro.inr.h
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
⊢ ∀ ⦃x : α⦄, x ∈ s ∩ Icc b c → edist ((naturalParameterization f s a ∘ variationOnFromTo f s a) x) (f x) = 0
state_after: case intro.intro.intro.intro.inr.h.intro.intro
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
x : α
xs : x ∈ s
left✝ : b ≤ x
right✝ : x ≤ c
⊢ edist ((naturalParameterization f s a ∘ variationOnFromTo f s a) x) (f x) = 0

tactic: exact edist_naturalParameterization_eq_zero hf as xs
state_before: case intro.intro.intro.intro.inr.h.intro.intro
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f✝ : ℝ → E
s✝ : Set ℝ
l : ℝ≥0
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a : α
as : a ∈ s
b : α
bs : b ∈ s
c : α
cs : c ∈ s
h : variationOnFromTo f s a b ≤ variationOnFromTo f s a c
bc : b ≤ c
x : α
xs : x ∈ s
left✝ : b ≤ x
right✝ : x ≤ c
⊢ edist ((naturalParameterization f s a ∘ variationOnFromTo f s a) x) (f x) = 0
state_after: no goals