def test_full_1d(): check_ff(get_ff_polyethylene(), FullCellDOF, 3, {})
def test_iso_1d(): check_ff(get_ff_polyethylene(), IsoCellDOF, 1, {})
def test_strain_1d(): check_ff(get_ff_polyethylene(), StrainCellDOF, 1, {})