def load_id01_monitor(logfile, scan_number):
    """
    Load the default monitor for a dataset measured at ID01.

    :param logfile: Silx SpecFile object containing the information about the scan and
     image numbers
    :param scan_number: the scan number to load
    :return: the default monitor values
    """
    labels = logfile[str(scan_number) + ".1"].labels  # motor scanned
    labels_data = logfile[str(scan_number) + ".1"].data  # motor scanned
    try:
        monitor = labels_data[labels.index("exp1"), :]  # mon2 monitor at ID01
    except ValueError:
        try:
            monitor = labels_data[labels.index("mon2"), :]  # exp1 for old data at ID01
        except ValueError:  # no monitor data
            raise ValueError("No available monitor data")
    return monitor