Function test_basic_assembly_constant

python/test/unit/fem/test_assembler.py:1457–1489

Tests assembly with Constant. The following test should be sensitive to order of flattening the matrix-valued constant.

(mode, dtype)

@pytest.mark.parametrize("mode", [GhostMode.none, GhostMode.shared_facet])
@dtype_parametrize
def test_basic_assembly_constant(mode, dtype):
    """Tests assembly with Constant.

    The following test should be sensitive to order of flattening the
    matrix-valued constant.
    """
    xtype = dtype(0).real.dtype
    mesh = create_unit_square(MPI.COMM_WORLD, 5, 5, ghost_mode=mode, dtype=xtype)
    V = functionspace(mesh, ("Lagrange", 1))
    u, v = ufl.TrialFunction(V), ufl.TestFunction(V)

    c = Constant(mesh, np.array([[1.0, 2.0], [5.0, 3.0]], dtype=dtype))

    a = inner(c[1, 0] * u, v) * dx + inner(c[1, 0] * u, v) * ds
    L = inner(c[1, 0], v) * dx + inner(c[1, 0], v) * ds
    a, L = form(a, dtype=dtype), form(L, dtype=dtype)

    # Initial assembly
    A1 = assemble_matrix(a)
    A1.scatter_reverse()

    b1 = assemble_vector(L)
    b1.scatter_reverse(la.InsertMode.add)

    c.value = [[1.0, 2.0], [3.0, 4.0]]

    A2 = assemble_matrix(a)
    A2.scatter_reverse()
    assert np.linalg.norm(A1.data * 3.0 - A2.data * 5.0) == pytest.approx(0.0, abs=1.0e-5)

    b2 = assemble_vector(L)
    b2.scatter_reverse(la.InsertMode.add)
    assert np.linalg.norm(b1.array * 3.0 - b2.array * 5.0) == pytest.approx(0.0, abs=1.0e-5)


def test_lambda_assembler():