'rank filter 15'

def test_rank15(self):

    expected = [[2, 3, 1, 4, 1], [5, 3, 7, 1, 1], [5, 5, 3, 3, 3]]
    footprint = [[1, 0, 1], [0, 1, 0]]
    for type in self.types:
        array = numpy.array([[3, 2, 5, 1, 4], [5, 8, 3, 7, 1], [5, 6, 9, 3, 5]], type)
        output = ndimage.rank_filter(array, 0, footprint=footprint, origin=[(-1), 0])
        assert_array_almost_equal(expected, output)
