Fixed #1162: make matrix_power accept lists etc. as input

2 files changed, 12 insertions, 1 deletions

diff --git a/numpy/core/defmatrix.py b/numpy/core/defmatrix.py
index cbb338469..354e40060 100644
--- a/numpy/core/defmatrix.py
+++ b/numpy/core/defmatrix.py
@@ -2,7 +2,7 @@ __all__ = ['matrix', 'bmat', 'mat', 'asmatrix']
 
 import sys
 import numeric as N
-from numeric import concatenate, isscalar, binary_repr, identity
+from numeric import concatenate, isscalar, binary_repr, identity, asanyarray
 from numerictypes import issubdtype
 
 # make translation table
@@ -115,6 +115,7 @@ def matrix_power(M,n):
            [ 0, -1]])
 
     """
+    M = asanyarray(M)
     if len(M.shape) != 2 or M.shape[0] != M.shape[1]:
         raise ValueError("input must be a square array")
     if not issubdtype(type(n),int):
diff --git a/numpy/core/tests/test_defmatrix.py b/numpy/core/tests/test_defmatrix.py
index e9f0d9a7f..40728bd29 100644
--- a/numpy/core/tests/test_defmatrix.py
+++ b/numpy/core/tests/test_defmatrix.py
@@ -1,5 +1,6 @@
 from numpy.testing import *
 from numpy.core import *
+from numpy.core.defmatrix import matrix_power
 import numpy as np
 
 class TestCtor(TestCase):
@@ -358,6 +359,15 @@ class TestNewScalarIndexing(TestCase):
         assert_array_equal(x[:,[1,0]],x[:,::-1])
         assert_array_equal(x[[2,1,0],:],x[::-1,:])
 
+class TestPower(TestCase):
+    def test_returntype(self):
+        a = array([[0,1],[0,0]])
+        assert type(matrix_power(a, 2)) is ndarray
+        a = mat(a)
+        assert type(matrix_power(a, 2)) is matrix
+
+    def test_list(self):
+        assert_array_equal(matrix_power([[0, 1], [0, 0]], 2), [[0, 0], [0, 0]])
 
 if __name__ == "__main__":
     run_module_suite()