'Aux method.'

def _pick_sources(self, data, include, exclude, eid):

    logger.info('Transforming    to    Xdawn    space')
    sources = np.dot(self.filters_[eid].T, data)
    if (include not in (None, list())):
        mask = np.ones(len(sources), dtype=np.bool)
        mask[np.unique(include)] = False
        sources[mask] = 0.0
        logger.info(('Zeroing    out    %i    Xdawn    components' % mask.sum()))
    elif (exclude not in (None, list())):
        exclude_ = np.unique(exclude)
        sources[exclude_] = 0.0
        logger.info(('Zeroing    out    %i    Xdawn    components' % len(exclude_)))
    logger.info('Inverse    transforming    to    sensor    space')
    data = np.dot(self.patterns_[eid], sources)
    return data
