def test_view_of_view(matrix_type, subset_func, subset_func2):
    adata = gen_adata((30, 15), X_type=matrix_type)
    adata.raw = adata
    if subset_func is single_subset:
        pytest.xfail("Other subset generating functions have trouble with this")
    var_s1 = subset_func(adata.var_names, min_size=4)
    var_view1 = adata[:, var_s1]
    var_s2 = subset_func2(var_view1.var_names)
    var_view2 = var_view1[:, var_s2]
    assert var_view2._adata_ref is adata
    obs_s1 = subset_func(adata.obs_names, min_size=4)
    obs_view1 = adata[obs_s1, :]
    obs_s2 = subset_func2(obs_view1.obs_names)
    assert adata[obs_s1, :][:, var_s1][obs_s2, :]._adata_ref is adata

    view_of_actual_copy = adata[:, var_s1].copy()[obs_s1, :].copy()[:, var_s2].copy()

    view_of_view_copy = adata[:, var_s1][obs_s1, :][:, var_s2].copy()

    assert_equal(view_of_actual_copy, view_of_view_copy, exact=True)
def demag_pos(isa, pos, icur=-1, ibeta=-1, ax=0):
    """plot demag of NC/I7/ISA7 model at rotor position
    Args:
      isa: Isa7/NC object
      pos: rotor position in degree
      icur: cur amplitude index or last index if -1
      ibeta: beta angle index or last index if -1
    """
    emag = [e for e in isa.elements if e.is_magnet()]
    demag = np.array([isa.demagnetization(e, icur, ibeta)[1]
                     for e in emag])
    for i, x in enumerate(isa.pos_el_fe_induction):
        if x >= pos/180*np.pi:
            break

    hpol = demag[:, i]
    hpol[hpol == 0] = np.nan
    _contour(ax, f'Demagnetization at Pos. {round(x/np.pi*180)}° ({isa.MAGN_TEMPERATURE} °C)',
             emag, hpol, '-H / kA/m', isa)
    logger.info("Max demagnetization %f kA/m", np.nanmax(hpol))