def METHOD_NAME():
    ds = data_dir_load(ep_cosmo)
    dso = [None, ("sphere", ("max", (0.1, "unitary")))]
    for dobj_name in dso:
        for field in _pfields:
            yield FieldValuesTest(ep_cosmo, field, dobj_name, particle_type=True)
        dobj = create_obj(ds, dobj_name)
        s1 = dobj[("index", "ones")].sum()
        s2 = sum(mask.sum() for block, mask in dobj.blocks)
        assert_equal(s1, s2)