chapter 3 finished

chapter3/Matrix.idr

@@ -0,0 +1,30 @@
+module Matrix
+
+import Data.Vect
+
+addMatrix : Num numType =>
+            Vect rows (Vect cols numType) ->
+            Vect rows (Vect cols numType) ->
+            Vect rows (Vect cols numType)
+addMatrix = zipWith (zipWith (+))
+
+multMatrix : Num numType =>
+              Vect n (Vect m numType) -> Vect m (Vect p numType) ->
+              Vect n (Vect p numType)
+-- 😔
+
+createEmpties : Vect n (Vect 0 elem)
+createEmpties = replicate _ []
+
+createEmpties2 : Vect n (Vect 0 elem)
+createEmpties2 {n = Z} = []
+createEmpties2 {n = (S k)} = [] :: createEmpties2
+
+
+transHelper : (x : Vect n elem) -> (xsTrans : Vect n (Vect len elem)) -> Vect n (Vect (S len) elem)
+transHelper = zipWith (\x, y => x :: y)
+
+transposeMat : Vect m (Vect n elem) -> Vect n (Vect m elem)
+transposeMat [] = createEmpties
+transposeMat (x :: xs) = let xsTrans = transposeMat xs in
+                           transHelper x xsTrans

chapter3/Vectors.idr

@@ -52,3 +52,12 @@ my_map f (x :: xs) = (f x) :: my_map f xs
 my_vect_map : (a -> b) -> Vect n a -> Vect n b
 my_vect_map _ [] = []
 my_vect_map f (x :: xs) = (f x) :: my_vect_map f xs
+
+
+lengthLong : Vect n elem -> Nat
+lengthLong [] = 0
+lengthLong (x :: xs) = S (lengthLong xs)
+
+
+lengthLong2 : Vect n elem -> Nat
+lengthLong2 {n} xs = n