def create_radar_template(actual_radar_file_name):
    """Create radar template file name from actual radar file name

    Parameters
    ----------
    actual_radar_file_name : string

    Returns
    -------
    radar_file_name_template : string or empty string

    """

    # Search for the word "tile". If not found, return empty string.
    # Otherwise, replace with "%%d".
    #
    # For example:
    # radar.2d.tile1.20140531.0500.nc -> radar.2d.tile%d.20140531.0500.nc

    pos = actual_radar_file_name.find("tile")
    if pos == -1:
        return ""

    out_string = "%stile%%d%s" % (actual_radar_file_name[0:pos], actual_radar_file_name[pos+5:])
    return out_string