def METHOD_NAME(voice_part_old, voice_part_tmp):
    # set length of voice_part
    ovn = len(voice_part_old)  # Number of Old Voice part
    tvn = len(voice_part_tmp)  # Number of Tmp Voice part
    # initialize output
    voice_part_new = np.zeros((ovn, 2), np.float)
    # merge voice_part & skip non_voice_part
    for i in range(ovn):
        for j in range(tvn):
            if (voice_part_old[i][0] <= voice_part_tmp[j][0]) and (
                voice_part_tmp[j][1] <= voice_part_old[i][1]
            ):
                if voice_part_new[i][0] == 0.0:
                    voice_part_new[i][0] = voice_part_tmp[j][0]
                voice_part_new[i][1] = voice_part_tmp[j][1]
    # check error
    for i in range(ovn):
        for j in range(2):
            if voice_part_new[i][j] == 0.0:
                sys.stderr.write("Error: Element[%d][%d] is zero.\n" % (i, j))
    return voice_part_new