name : test_multiarray.py import numpy as np from numpy.testing import assert_, assert_equal, assert_array_equal class TestView: def test_type(self): x = np.array([1, 2, 3]) assert_(isinstance(x.view(np.matrix), np.matrix)) def test_keywords(self): x = np.array([(1, 2)], dtype=[('a', np.int8), ('b', np.int8)]) # We must be specific about the endianness here: y = x.view(dtype='<i2', type=np.matrix) assert_array_equal(y, [[513]]) assert_(isinstance(y, np.matrix)) assert_equal(y.dtype, np.dtype('<i2'))