def test_view_failed_delitem(attr):
    adata = gen_adata((10, 10))
    view = adata[5:7, :][:, :5]
    adata_hash = joblib.hash(adata)
    view_hash = joblib.hash(view)

    with pytest.raises(KeyError):
        getattr(view, attr).__delitem__("not a key")

    assert view.is_view
    assert adata_hash == joblib.hash(adata)
    assert view_hash == joblib.hash(view)
def forcedens_surface(fdens, ax=0):
    if ax == 0:
        _create_3d_axis()
        ax = plt.gca()
    xpos = [p for p in fdens.positions[0]['X']]
    ypos = [p['position'] for p in fdens.positions]
    z = 1e-3*np.array([p['FN']
                       for p in fdens.positions])
    _plot_surface(ax, xpos, ypos, z,
                  (u'Rotor pos/°', u'Pos/°', u'F N / kN/m²'))