def METHOD_NAME(self):
    dx = 0.25
    rad = 10
    mesh = mesh_builder_xyz(
        np.c_[0.01, 0.01, 0.01],
        [dx, dx, dx],
        depth_core=0,
        padding_distance=[[0, 20], [0, 20], [0, 20]],
        mesh_type="TREE",
    )
    radCell = int(np.ceil(rad / dx))
    mesh = refine_tree_xyz(
        mesh,
        np.c_[0, 0, 0],
        octree_levels=[radCell],
        method="radial",
        finalize=True,
    )
    cell_levels = mesh.cell_levels_by_index(np.arange(mesh.n_cells))
    vol = 4.0 * np.pi / 3.0 * (rad + dx) ** 3.0
    vol_mesh = mesh.cell_volumes[cell_levels == mesh.max_level].sum()
    self.assertLess(np.abs(vol - vol_mesh) / vol, 0.05)
    levels, cells_per_level = np.unique(cell_levels, return_counts=True)
    self.assertEqual(mesh.n_cells, 311858)
    np.testing.assert_array_equal(levels, [3, 4, 5, 6, 7])
    np.testing.assert_array_equal(cells_per_level, [232, 1176, 2671, 9435, 298344])