def l_min(s, m):
    """ Minimum allowed value of l for a given s, m.

    The formula is l_min = max(\|m\|,\|s\|).

    Parameters
    ----------
    s: int
      Spin-weight of interest

    m: int
      Magnetic quantum number

    Returns
    -------
    int
      l_min
    """

    return max(abs(s), abs(m))