def get_source_data_path(config, subdir_num):
    """
    Return the source data path for the given subdir number

    :param config: Config dictionary
    :param subdir_num: Number of subdir
    :return: Full path to given source data
    """
    # assume data is a list corresponding with subdirs
    data_paths = config["source_data_paths"]
    if not isinstance(data_paths, list):
        raise RuntimeError(
            "Unexpected, source_data_paths entry in config should be a list corresponding with subdirs"
        )
    if subdir_num >= len(data_paths):
        raise RuntimeError(
            "Unexpected, could not get source_data_paths entry %d, found %d in list"
            % (subdir_num, len(data_paths))
        )

    return data_paths[subdir_num]