'Aux Method.'

def _check_target(self, target, inst, start, stop, reject_by_annotation=False):

    if isinstance(inst, BaseRaw):
        reject_by_annotation = ('omit' if reject_by_annotation else None)
        (start, stop) = _check_start_stop(inst, start, stop)
        if hasattr(target, 'ndim'):
            if (target.ndim < 2):
                target = target.reshape(1, target.shape[(-1)])
        if isinstance(target, string_types):
            pick = _get_target_ch(inst, target)
            target = inst.get_data(pick, start, stop, reject_by_annotation)
    elif isinstance(inst, BaseEpochs):
        if isinstance(target, string_types):
            pick = _get_target_ch(inst, target)
            target = inst.get_data()[:, pick]
        if hasattr(target, 'ndim'):
            if ((target.ndim == 3) and (min(target.shape) == 1)):
                target = target.ravel()
    elif isinstance(inst, Evoked):
        if isinstance(target, string_types):
            pick = _get_target_ch(inst, target)
            target = inst.data[pick]
    return target
