def METHOD_NAME(self):
    """
    tests:
     - xyz_to_rtp_array
     - rtp_to_xyz_array
    """
    xyz1 = [
        [0., 0., 0.],
        [1., 0., 0.],
        [1., 2., 0.],
        [1., 2., 3.],
    ]
    rtp = xyz_to_rtp_array(xyz1)
    xyz2 = rtp_to_xyz_array(rtp)
    assert np.allclose(xyz1, xyz2), 'xyz1:\n%s\nxyz2:\n%s' % (xyz1, xyz2)