def test_view_of_view_modification():
    adata = ad.AnnData(np.zeros((10, 10)))
    adata[0, :][:, 5:].X = np.ones(5)
    assert np.all(adata.X[0, 5:] == np.ones(5))
    adata[[1, 2], :][:, [1, 2]].X = np.ones((2, 2))
    assert np.all(adata.X[1:3, 1:3] == np.ones((2, 2)))

    adata.X = sparse.csr_matrix(adata.X)
    adata[0, :][:, 5:].X = np.ones(5) * 2
    assert np.all(asarray(adata.X)[0, 5:] == np.ones(5) * 2)
    adata[[1, 2], :][:, [1, 2]].X = np.ones((2, 2)) * 2
    assert np.all(asarray(adata.X)[1:3, 1:3] == np.ones((2, 2)) * 2)
def _plot_surface(ax, x, y, z, labels, azim=None):
    """helper function for surface plots"""
    # ax.tick_params(axis='both', which='major', pad=-3)
    assert np.size(x) > 1 and np.size(y) > 1 and np.size(z) > 1
    if azim is not None:
        ax.azim = azim
    X, Y = np.meshgrid(x, y)
    Z = np.ma.masked_invalid(z)
    ax.plot_surface(X, Y, Z,
                    rstride=1, cstride=1,
                    cmap=cm.viridis, alpha=0.85,
                    vmin=np.nanmin(z), vmax=np.nanmax(z),
                    linewidth=0, antialiased=True)