March 2014 update

Task/Matrix-exponentiation-operator/Maple/matrix-exponentiation-operator-1.maple

@@ -0,0 +1,2 @@
+> M := <<1,2>|<3,4>>;
+> M ^ 2;

Task/Matrix-exponentiation-operator/Maple/matrix-exponentiation-operator-2.maple

@@ -0,0 +1,2 @@
+> M := <<1,2>|<3,4>>;
+> M ^~ 2;

Task/Matrix-exponentiation-operator/Scheme/matrix-exponentiation-operator.ss

@@ -0,0 +1,23 @@
+(define (dec x)
+  (- x 1))
+
+(define (halve x)
+  (/ x 2))
+
+(define (row*col row col)
+  (apply + (map * row col)))
+
+(define (matrix-multiply m1 m2)
+  (map
+    (lambda (row)
+      (apply map (lambda col (row*col row col))
+        m2))
+    m1))
+
+(define (matrix-exp mat exp)
+  (cond ((= exp 1) mat)
+        ((even? exp) (square-matrix (matrix-exp mat (halve exp))))
+        (else (matrix-multiply mat (matrix-exp mat (dec exp))))))
+
+(define (square-matrix mat)
+  (matrix-multiply mat mat))