'Aux method.'

def _apply_raw(self, raw, include, exclude, event_id, picks):

    if (not raw.preload):
        raise ValueError('Raw    data    must    be    preloaded    to    apply    Xdawn')
    raws = dict()
    for eid in event_id:
        data = raw[picks, :][0]
        data = self._pick_sources(data, include, exclude, eid)
        raw_r = raw.copy()
        raw_r[picks, :] = data
        raws[eid] = raw_r
    return raws
