def mask_wave(wave, mask):
    """
    Mask wave data.
    :param wave:
        wave data, an numpy array.
    :param mask:
        a list of mask tuples, see make_mask function.
    :return:
        masked wave data, a list of numpy arrays.
    """
    masked_wave = list()
    for (begin, end) in mask:
        masked_wave.append(wave[begin:end])
        pass
    return masked_wave