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 forcedens_fft(title, fdens, ax=0):
    """plot force densities FFT
    Args:
      title: plot title
      fdens: force density object
    """
    if ax == 0:
        ax = plt.axes(projection="3d")

    F = 1e-3*fdens.fft()
    fmin = 0.2
    num_bars = F.shape[0] + 1
    _xx, _yy = np.meshgrid(np.arange(1, num_bars),
                           np.arange(1, num_bars))
    z_size = F[F > fmin]
    x_pos, y_pos = _xx[F > fmin], _yy[F > fmin]
    z_pos = np.zeros_like(z_size)
    x_size = 2
    y_size = 2

    ax.bar3d(x_pos, y_pos, z_pos, x_size, y_size, z_size)
    ax.view_init(azim=120)
    ax.set_xlim(0, num_bars+1)
    ax.set_ylim(0, num_bars+1)
    ax.set_title(title)
    ax.set_xlabel('M')
    ax.set_ylabel('N')
    ax.set_zlabel('kN/m²')