sph.py 文件源码

def spneumann(n, kr):
    """Spherical Neumann (Bessel second kind) of order n at kr

    Parameters
    ----------
    n : array_like
       Order
    kr: array_like
       Argument

    Returns
    -------
    Yv : complex float
       Spherical Neumann (Bessel second kind)
    """
    n, kr = scalar_broadcast_match(n, kr)

    if _np.any(n < 0) | _np.any(_np.mod(n, 1) != 0):
        Yv = _np.full(kr.shape, _np.nan, dtype=_np.complex_)

        kr_non_zero = kr != 0
        Yv[kr_non_zero] = _np.lib.scimath.sqrt(_np.pi / 2 / kr[kr_non_zero]) * neumann(n[kr_non_zero] + 0.5, kr[kr_non_zero])
        Yv[kr < 0] = -Yv[kr < 0]
    else:
        Yv = scy.spherical_yn(n.astype(_np.int), kr)
        Yv[_np.isinf(Yv)] = _np.nan  # return possible infs as nan to stay consistent
    return _np.squeeze(Yv)