def _rockstar_method(ds, **finder_kwargs):
    """
    Run the Rockstar halo finding method.
    """
    from yt.frontends.rockstar.data_structures import RockstarDataset
    from yt.analysis_modules.halo_finding.rockstar.api import RockstarHaloFinder
    rh = RockstarHaloFinder(ds, **finder_kwargs)
    rh.run()
    if 'outbase' in finder_kwargs:
        outbase = finder_kwargs['outbase']
    else:
        outbase = 'rockstar_halos'
    halos_ds = RockstarDataset(outbase + '/halos_0.0.bin')
    try:
        halos_ds.create_field_info()
    except ValueError:
        return None
    return halos_ds
