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 __init__(self, head):
        self.head = head
        self.lsize = 0
        while head.next:
            head = head.next
            self.lsize += 1

        self.m1_idx = None
        self.m2_idx = None
        if self.lsize > self._largesize:
            self.m1_idx = self.lsize / 3   # start from 1/3
            self.m1 = self._getN(self.m1_idx)
            self.m2_idx = self.m1_idx * 2  # start from 2/3
            self.m2 = self._getN(self.m2_idx)