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 select(cls, dataset, selection_mask=None, **selection):
        df = dataset.data
        if selection_mask is None:
            selection_mask = cls.select_mask(dataset, selection)

        indexed = cls.indexed(dataset, selection)
        if selection_mask is not None:
            df = df.loc[selection_mask]
        if indexed and len(df) == 1 and len(dataset.vdims) == 1:
            return df[dataset.vdims[0].name].iloc[0]
        return df