def test_vector_field_shape():
mesh = CuboidMesh(1, 1, 1, 2, 3, 4)
expected_nb_cells = 2 * 3 * 4
expected_shape_for_vector_field = (expected_nb_cells, 3)
assert mesh.vector_shape() == expected_shape_for_vector_field
m = np.zeros(mesh.vector_shape()) # usage example
