Function test_eval

python/test/unit/fem/test_function.py:63–98

(V, W, Q, mesh)

def test_eval(V, W, Q, mesh):
    u1 = Function(V)
    u2 = Function(W)
    u3 = Function(Q)

    def e2(x):
        values = np.empty((3, x.shape[1]))
        values[0] = x[0] + x[1] + x[2]
        values[1] = x[0] - x[1] - x[2]
        values[2] = x[0] + x[1] + x[2]
        return values

    def e3(x):
        values = np.empty((9, x.shape[1]))
        values[0] = x[0] + x[1] + x[2]
        values[1] = x[0] - x[1] - x[2]
        values[2] = x[0] + x[1] + x[2]
        values[3] = x[0]
        values[4] = x[1]
        values[5] = x[2]
        values[6] = -x[0]
        values[7] = -x[1]
        values[8] = -x[2]
        return values

    u1.interpolate(lambda x: x[0] + x[1] + x[2])
    u2.interpolate(e2)
    u3.interpolate(e3)

    x0 = (mesh.geometry.x[0] + mesh.geometry.x[1]) / 2.0
    tree = bb_tree(mesh, mesh.topology.dim, padding=0.0)
    cell_candidates = compute_collisions_points(tree, x0)
    cell = compute_colliding_cells(mesh, cell_candidates, x0).array
    assert len(cell) > 0
    first_cell = cell[0]
    assert np.allclose(u3.eval(x0, first_cell)[:3], u2.eval(x0, first_cell), rtol=1e-15, atol=1e-15)


@pytest.mark.skip_in_parallel