September Morn Update

Task/Matrix-exponentiation-operator/Python/matrix-exponentiation-operator-2.py

@@ -0,0 +1,32 @@
+class Mat(list) :
+    def __matmul__(self, B) :
+        A = self
+        return Mat([[sum(A[i][k]*B[k][j] for k in range(len(B)))
+                    for j in range(len(B[0])) ] for i in range(len(A))])
+
+
+def identity(size):
+    size = range(size)
+    return [[(i==j)*1 for i in size] for j in size]
+
+def power(F, n):
+    result = Mat(identity(len(F)))
+    b = Mat(F)
+    while n > 0:
+        if (n%2) == 0:
+            b = b @ b
+            n //= 2
+        else:
+            result = b @ result
+            b = b @ b
+            n //= 2
+    return result
+
+def printtable(data):
+    for row in data:
+        print (' '.join('%-5s' % ('%s' % cell) for cell in row))
+
+m = [[3,2], [2,1]]
+for i in range(5):
+    print('\n%i:' % i)
+    printtable(power(m, i))