def METHOD_NAME(self, channel_ids):
    """channel_ids is a  numpy int array the same length as the number of energy sources,
    that specifies the mapping of structure factor to energy channel,
    allowing one to refine multiple energy-dependent structure factors
    for example in a two-color experiment
    """
    assert isinstance(channel_ids, np.ndarray)
    channel_ids = self._check_contig(channel_ids)
    if channel_ids.dtype != np.int32:
        channel_ids = channel_ids.astype(np.int32)
    # assert len(channel_ids)== number_of_sources
    self.__update_Fhkl_channels(channel_ids)