Merge pull request #5048 from juliantaylor/subclass-test-fix

juliantaylor · juliantaylor · commit 859d2f13c6a6 · 2014-09-05T00:57:48.000+02:00
BUG: fix array_almost_equal for array subclasses
diff --git a/numpy/testing/tests/test_utils.py b/numpy/testing/tests/test_utils.py
@@ -244,6 +244,14 @@ def test_inf(self):
         self.assertRaises(AssertionError,
                 lambda : self._assert_func(a, b))
 
+    def test_subclass(self):
+        a = np.array([[1., 2.], [3., 4.]])
+        b = np.ma.masked_array([[1., 2.], [0., 4.]],
+                               [[False, False], [True, False]])
+        assert_array_almost_equal(a, b)
+        assert_array_almost_equal(b, a)
+        assert_array_almost_equal(b, b)
+
 class TestAlmostEqual(_GenericTest, unittest.TestCase):
     def setUp(self):
         self._assert_func = assert_almost_equal
diff --git a/numpy/testing/utils.py b/numpy/testing/utils.py
@@ -829,7 +829,7 @@ def compare(x, y):
         # make sure y is an inexact type to avoid abs(MIN_INT); will cause
         # casting of x later.
         dtype = result_type(y, 1.)
-        y = array(y, dtype=dtype, copy=False)
+        y = array(y, dtype=dtype, copy=False, subok=True)
         z = abs(x-y)
 
         if not issubdtype(z.dtype, number):
