Module: Mathlib.Analysis.Convex.BetweenList

Goal state before:
pp: case neg
R : Type u_1
V : Type u_2
P : Type u_4
inst✝⁵ : Field R
inst✝⁴ : LinearOrder R
inst✝³ : IsStrictOrderedRing R
inst✝² : AddCommGroup V
inst✝¹ : Module R V
inst✝ : AddTorsor V P
head : P
l'' : List R
hl''0 : ∀ a ∈ l'', 0 ≤ a
hl''s : l''.SortedLE
tail : List P
ht2 : ¬tail = []
r : R
hr0 : 0 ≤ r
hr1 : r ≤ 1
hl : head :: (lineMap head (tail.getLast ht2)) r :: tail ≠ []
h :
  ((∀ a' ∈ tail, Wbtw R head ((lineMap head (tail.getLast ht2)) r) a') ∧ Pairwise (Wbtw R head) tail) ∧
    List.Wbtw R ((lineMap head (tail.getLast ht2)) r :: tail)
ht : ¬(lineMap head (tail.getLast ht2)) r :: tail = []
hl'' :
  map (⇑(lineMap ((lineMap head (tail.getLast ht2)) r) (tail.getLast ht2))) l'' =
    (lineMap head (tail.getLast ht2)) r :: tail
⊢ ∃ l',
    (∀ a ∈ l', 0 ≤ a) ∧
      l'.SortedLE ∧ map (⇑(lineMap head (tail.getLast ht2))) l' = head :: (lineMap head (tail.getLast ht2)) r :: tail

Tactic:
refine ⟨0 :: l''.map fun x ↦ r + (1 - r) * x, ?_, ?_, ?_⟩

Goal state after:
case neg.refine_1
R : Type u_1
V : Type u_2
P : Type u_4
inst✝⁵ : Field R
inst✝⁴ : LinearOrder R
inst✝³ : IsStrictOrderedRing R
inst✝² : AddCommGroup V
inst✝¹ : Module R V
inst✝ : AddTorsor V P
head : P
l'' : List R
hl''0 : ∀ a ∈ l'', 0 ≤ a
hl''s : l''.SortedLE
tail : List P
ht2 : ¬tail = []
r : R
hr0 : 0 ≤ r
hr1 : r ≤ 1
hl : head :: (lineMap head (tail.getLast ht2)) r :: tail ≠ []
h :
  ((∀ a' ∈ tail, Wbtw R head ((lineMap head (tail.getLast ht2)) r) a') ∧ Pairwise (Wbtw R head) tail) ∧
    List.Wbtw R ((lineMap head (tail.getLast ht2)) r :: tail)
ht : ¬(lineMap head (tail.getLast ht2)) r :: tail = []
hl'' :
  map (⇑(lineMap ((lineMap head (tail.getLast ht2)) r) (tail.getLast ht2))) l'' =
    (lineMap head (tail.getLast ht2)) r :: tail
⊢ ∀ a ∈ 0 :: map (fun x ↦ r + (1 - r) * x) l'', 0 ≤ a

case neg.refine_2
R : Type u_1
V : Type u_2
P : Type u_4
inst✝⁵ : Field R
inst✝⁴ : LinearOrder R
inst✝³ : IsStrictOrderedRing R
inst✝² : AddCommGroup V
inst✝¹ : Module R V
inst✝ : AddTorsor V P
head : P
l'' : List R
hl''0 : ∀ a ∈ l'', 0 ≤ a
hl''s : l''.SortedLE
tail : List P
ht2 : ¬tail = []
r : R
hr0 : 0 ≤ r
hr1 : r ≤ 1
hl : head :: (lineMap head (tail.getLast ht2)) r :: tail ≠ []
h :
  ((∀ a' ∈ tail, Wbtw R head ((lineMap head (tail.getLast ht2)) r) a') ∧ Pairwise (Wbtw R head) tail) ∧
    List.Wbtw R ((lineMap head (tail.getLast ht2)) r :: tail)
ht : ¬(lineMap head (tail.getLast ht2)) r :: tail = []
hl'' :
  map (⇑(lineMap ((lineMap head (tail.getLast ht2)) r) (tail.getLast ht2))) l'' =
    (lineMap head (tail.getLast ht2)) r :: tail
⊢ (0 :: map (fun x ↦ r + (1 - r) * x) l'').SortedLE

case neg.refine_3
R : Type u_1
V : Type u_2
P : Type u_4
inst✝⁵ : Field R
inst✝⁴ : LinearOrder R
inst✝³ : IsStrictOrderedRing R
inst✝² : AddCommGroup V
inst✝¹ : Module R V
inst✝ : AddTorsor V P
head : P
l'' : List R
hl''0 : ∀ a ∈ l'', 0 ≤ a
hl''s : l''.SortedLE
tail : List P
ht2 : ¬tail = []
r : R
hr0 : 0 ≤ r
hr1 : r ≤ 1
hl : head :: (lineMap head (tail.getLast ht2)) r :: tail ≠ []
h :
  ((∀ a' ∈ tail, Wbtw R head ((lineMap head (tail.getLast ht2)) r) a') ∧ Pairwise (Wbtw R head) tail) ∧
    List.Wbtw R ((lineMap head (tail.getLast ht2)) r :: tail)
ht : ¬(lineMap head (tail.getLast ht2)) r :: tail = []
hl'' :
  map (⇑(lineMap ((lineMap head (tail.getLast ht2)) r) (tail.getLast ht2))) l'' =
    (lineMap head (tail.getLast ht2)) r :: tail
⊢ map (⇑(lineMap head (tail.getLast ht2))) (0 :: map (fun x ↦ r + (1 - r) * x) l'') =
    head :: (lineMap head (tail.getLast ht2)) r :: tail