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chore(library/data/vector): cleanup vector proofs

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This commit is contained in:
Leonardo de Moura 2015-03-06 17:37:03 -08:00
parent 1490bdad49
commit 4fdac068b0
1 changed files with 8 additions and 8 deletions
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16
library/data/vector.lean
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@ -84,8 +84,8 @@ namespace vector
-- Remark: why do we need to provide indices?
definition append : Π {n m : nat}, vector A n → vector A m → vector A (n ⊕ m)
| @append 0 m nil w := w
| @append (succ n) m (a::v) w := a :: (append v w)
| 0 m nil w := w
| (succ n) m (a::v) w := a :: (append v w)
theorem append_nil {n : nat} (v : vector A n) : append nil v = v :=
rfl
@ -117,16 +117,16 @@ namespace vector
rfl
theorem unzip_zip : ∀ {n : nat} (v₁ : vector A n) (v₂ : vector B n), unzip (zip v₁ v₂) = (v₁, v₂)
| @unzip_zip 0 nil nil := rfl
| @unzip_zip (succ n) (a::va) (b::vb) := calc
| 0 nil nil := rfl
| (succ n) (a::va) (b::vb) := calc
unzip (zip (a :: va) (b :: vb))
= (a :: pr₁ (unzip (zip va vb)), b :: pr₂ (unzip (zip va vb))) : rfl
... = (a :: pr₁ (va, vb), b :: pr₂ (va, vb)) : {unzip_zip va vb}
... = (a :: va, b :: vb) : rfl
theorem zip_unzip : ∀ {n : nat} (v : vector (A × B) n), zip (pr₁ (unzip v)) (pr₂ (unzip v)) = v
| @zip_unzip 0 nil := rfl
| @zip_unzip (succ n) ((a, b) :: v) := calc
| 0 nil := rfl
| (succ n) ((a, b) :: v) := calc
zip (pr₁ (unzip ((a, b) :: v))) (pr₂ (unzip ((a, b) :: v)))
= (a, b) :: zip (pr₁ (unzip v)) (pr₂ (unzip v)) : rfl
... = (a, b) :: v : {zip_unzip v}
@ -144,8 +144,8 @@ namespace vector
rfl
theorem last_concat : ∀ {n : nat} (v : vector A n) (a : A), last (concat v a) = a
| @last_concat 0 nil a := rfl
| @last_concat (succ n) (b::v) a := calc
| 0 nil a := rfl
| (succ n) (b::v) a := calc
last (concat (b::v) a) = last (concat v a) : rfl
... = a : last_concat v a
end vector