numerate multiple sets of
        coefficients.

    Returns
    -------
    values : ndarray, compatible object
        The values of the multidimensional polynomial on points formed with
        triples of corresponding values from `x`, `y`, and `z`.

    See Also
    --------
    polyval, polyval2d, polygrid2d, polygrid3d

    Notes
    -----

    .. versionadded:: 1.7.0

    ra