def test_cumvar(): arr = np.random.randn(3, 4) cum_arr = cumvar(arr, axis = 1, sample = False) assert np.allclose(cum_arr[:, 0], 0) assert np.allclose(cum_arr[:, 1], np.var(arr[:, :2], axis = 1)) assert np.allclose(cum_arr[:, 2], np.var(arr[:, :3], axis = 1))