test_nditer.py 文件源码

def test_iter_buffered_cast_byteswapped():
    # Test that buffering can handle a cast which requires swap->cast->swap

    a = np.arange(10, dtype='f4').newbyteorder().byteswap()
    i = nditer(a, ['buffered', 'external_loop'],
                   [['readwrite', 'nbo', 'aligned']],
                   casting='same_kind',
                   op_dtypes=[np.dtype('f8').newbyteorder()],
                   buffersize=3)
    for v in i:
        v[...] *= 2

    assert_equal(a, 2*np.arange(10, dtype='f4'))

    try:
        warnings.simplefilter("ignore", np.ComplexWarning)

        a = np.arange(10, dtype='f8').newbyteorder().byteswap()
        i = nditer(a, ['buffered', 'external_loop'],
                       [['readwrite', 'nbo', 'aligned']],
                       casting='unsafe',
                       op_dtypes=[np.dtype('c8').newbyteorder()],
                       buffersize=3)
        for v in i:
            v[...] *= 2

        assert_equal(a, 2*np.arange(10, dtype='f8'))
    finally:
        warnings.simplefilter("default", np.ComplexWarning)