Пример #1
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def test_call(R, V, W, Q, mesh):
    u0 = Function(R)
    u1 = Function(V)
    u2 = Function(W)
    u3 = Function(Q)

    @function.expression.numba_eval
    def expr_eval1(values, x, cell_idx):
        values[:, 0] = x[:, 0] + x[:, 1] + x[:, 2]

    e1 = Expression(expr_eval1)

    @function.expression.numba_eval
    def expr_eval2(values, x, cell_idx):
        values[:, 0] = x[:, 0] + x[:, 1] + x[:, 2]
        values[:, 1] = x[:, 0] - x[:, 1] - x[:, 2]
        values[:, 2] = x[:, 0] + x[:, 1] + x[:, 2]

    e2 = Expression(expr_eval2, shape=(3, ))

    @function.expression.numba_eval
    def expr_eval3(values, x, cell_idx):
        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]

    e3 = Expression(expr_eval3, shape=(3, 3))

    u0.vector()[:] = 1.0
    u1.interpolate(e1)
    u2.interpolate(e2)
    u3.interpolate(e3)

    p0 = ((Vertex(mesh, 0).point() + Vertex(mesh, 1).point()) / 2.0).array()
    x0 = (mesh.geometry.x(0) + mesh.geometry.x(1)) / 2.0

    assert numpy.allclose(u0(x0), u0(x0))
    assert numpy.allclose(u0(x0), u0(p0))
    assert numpy.allclose(u1(x0), u1(x0))
    assert numpy.allclose(u1(x0), u1(p0))
    assert numpy.allclose(u2(x0)[0], u1(p0))

    assert numpy.allclose(u2(x0), u2(p0))
    assert numpy.allclose(u3(x0)[:3], u2(x0), rtol=1e-15, atol=1e-15)

    p0_list = [p for p in p0]
    x0_list = [x for x in x0]
    assert numpy.allclose(u0(x0_list), u0(x0_list))
    assert numpy.allclose(u0(x0_list), u0(p0_list))

    with pytest.raises(ValueError):
        u0([0, 0, 0, 0])
    with pytest.raises(ValueError):
        u0([0, 0])
Пример #2
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def hat_function_grad(vertex, cell):
    """Compute L^\infty-norm of gradient of hat function on 'cell'
    and value 1 in 'vertex'."""
    # TODO: fix using ghosted mesh
    not_working_in_parallel("function 'hat_function_grad'")

    assert vertex in vertices(cell), "vertex not in cell!"

    # Find adjacent facet
    f = [f for f in facets(cell) if not vertex in vertices(f)]
    assert len(f) == 1, "Something strange with adjacent cell!"
    f = f[0]

    # Get unit normal
    n = f.normal()
    n /= n.norm()

    # Pick some vertex on facet
    # FIXME: Is it correct index in parallel?
    facet_vertex_0 = Vertex(cell.mesh(), f.entities(0)[0])

    # Compute signed distance from vertex to facet plane
    d = (facet_vertex_0.point() - vertex.point()).dot(n)

    # Return norm of gradient
    assert d != 0.0, "Degenerate cell!"
    return 1.0/abs(d)
Пример #3
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def test_call(R, V, W, Q, mesh):
    u0 = Function(R)
    u1 = Function(V)
    u2 = Function(W)
    u3 = Function(Q)

    def e1(values, x):
        values[:, 0] = x[:, 0] + x[:, 1] + x[:, 2]

    def e2(values, x):
        values[:, 0] = x[:, 0] + x[:, 1] + x[:, 2]
        values[:, 1] = x[:, 0] - x[:, 1] - x[:, 2]
        values[:, 2] = x[:, 0] + x[:, 1] + x[:, 2]

    def e3(values, x):
        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]

    u0.vector().set(1.0)
    u1.interpolate(e1)
    u2.interpolate(e2)
    u3.interpolate(e3)

    p0 = ((Vertex(mesh, 0).point() + Vertex(mesh, 1).point()) / 2.0)
    x0 = (mesh.geometry.x(0) + mesh.geometry.x(1)) / 2.0

    tree = cpp.geometry.BoundingBoxTree(mesh, mesh.geometry.dim)

    assert np.allclose(u0(x0, tree), u0(x0, tree))
    assert np.allclose(u0(x0, tree), u0(p0, tree))
    assert np.allclose(u1(x0, tree), u1(x0, tree))
    assert np.allclose(u1(x0, tree), u1(p0, tree))
    assert np.allclose(u2(x0, tree)[0], u1(p0, tree))

    assert np.allclose(u2(x0, tree), u2(p0, tree))
    assert np.allclose(u3(x0, tree)[:3], u2(x0, tree), rtol=1e-15, atol=1e-15)

    p0_list = [p for p in p0]
    x0_list = [x for x in x0]
    assert np.allclose(u0(x0_list, tree), u0(x0_list, tree))
    assert np.allclose(u0(x0_list, tree), u0(p0_list, tree))

    with pytest.raises(ValueError):
        u0([0, 0, 0, 0], tree)
    with pytest.raises(ValueError):
        u0([0, 0], tree)
Пример #4
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def facet_length(facet):
    """ calculate FEniCS facet length """
    v_idx = facet.entities(0)
    v0 = Vertex(facet.mesh(), v_idx[0])
    v1 = Vertex(facet.mesh(), v_idx[1])
    x0 = v0.point().x()
    x1 = v1.point().x()
    y0 = v0.point().y()
    y1 = v1.point().y()
    return ((x1 - x0)**2 + (y1 - y0)**2)**0.5
Пример #5
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def test_call(R, V, W, Q, mesh):
    u0 = Function(R)
    u1 = Function(V)
    u2 = Function(W)
    u3 = Function(Q)

    e1 = Expression("x[0] + x[1] + x[2]", degree=1)
    e2 = Expression(
        ("x[0] + x[1] + x[2]", "x[0] - x[1] - x[2]", "x[0] + x[1] + x[2]"),
        degree=1)
    e3 = Expression(
        (("x[0] + x[1] + x[2]", "x[0] - x[1] - x[2]", "x[0] + x[1] + x[2]"),
         ("x[0]", "x[1]", "x[2]"), ("-x[0]", "-x[1]", "-x[2]")),
        degree=1)

    u0.vector()[:] = 1.0
    u1.interpolate(e1)
    u2.interpolate(e2)
    u3.interpolate(e3)

    p0 = ((Vertex(mesh, 0).point() + Vertex(mesh, 1).point()) / 2.0).array()
    x0 = (mesh.geometry.x(0) + mesh.geometry.x(1)) / 2.0

    assert numpy.allclose(u0(x0), u0(x0))
    assert numpy.allclose(u0(x0), u0(p0))
    assert numpy.allclose(u1(x0), u1(x0))
    assert numpy.allclose(u1(x0), u1(p0))
    assert numpy.allclose(u2(x0)[0], u1(p0))

    assert numpy.allclose(u2(x0), u2(p0))
    assert numpy.allclose(u3(x0)[:3], u2(x0), rtol=1e-15, atol=1e-15)

    p0_list = [p for p in p0]
    x0_list = [x for x in x0]
    assert numpy.allclose(u0(x0_list), u0(x0_list))
    assert numpy.allclose(u0(x0_list), u0(p0_list))

    with pytest.raises(ValueError):
        u0([0, 0, 0, 0])
    with pytest.raises(ValueError):
        u0([0, 0])
Пример #6
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def test_call(R, V, W, Q, mesh):
    from numpy import all, allclose
    u0 = Function(R)
    u1 = Function(V)
    u2 = Function(W)
    u3 = Function(Q)

    e0 = Expression("x[0] + x[1] + x[2]", degree=1)
    e1 = Expression(
        ("x[0] + x[1] + x[2]", "x[0] - x[1] - x[2]", "x[0] + x[1] + x[2]"),
        degree=1)
    e2 = Expression(
        (("x[0] + x[1] + x[2]", "x[0] - x[1] - x[2]", "x[0] + x[1] + x[2]"),
         ("x[0]", "x[1]", "x[2]"), ("-x[0]", "-x[1]", "-x[2]")),
        degree=1)

    u0.vector()[:] = 1.0
    u1.interpolate(e0)
    u2.interpolate(e1)
    u3.interpolate(e2)

    p0 = ((Vertex(mesh, 0).point() + Vertex(mesh, 1).point()) / 2.0).array()
    x0 = (mesh.geometry.x(0) + mesh.geometry.x(1)) / 2.0

    assert round(u0(x0)[0] - u0(x0)[0], 7) == 0
    assert round(u0(x0)[0] - u0(p0)[0], 7) == 0
    assert round(u1(x0)[0] - u1(x0)[0], 7) == 0
    assert round(u1(x0)[0] - u1(p0)[0], 7) == 0
    assert round(u2(x0)[0][0] - u1(p0)[0], 7) == 0

    assert all(u2(x0) == u2(x0))
    assert all(u2(x0) == u2(p0))
    assert allclose(u3(x0)[0][:3], u2(x0)[0], rtol=1e-15, atol=1e-15)

    with pytest.raises(TypeError):
        u0([0, 0, 0, 0])
    with pytest.raises(TypeError):
        u0([0, 0])
Пример #7
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def test_near_evaluations(R, mesh):
    # Test that we allow point evaluation that are slightly outside

    u0 = Function(R)
    u0.vector()[:] = 1.0
    a = Vertex(mesh, 0).point().array()
    offset = 0.99 * DOLFIN_EPS

    a_shift_x = Point(a[0] - offset, a[1], a[2]).array()
    assert round(u0(a)[0] - u0(a_shift_x)[0], 7) == 0

    a_shift_xyz = Point(a[0] - offset / sqrt(3), a[1] - offset / sqrt(3),
                        a[2] - offset / sqrt(3)).array()
    assert round(u0(a)[0] - u0(a_shift_xyz)[0], 7) == 0
Пример #8
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def test_near_evaluations(R, mesh):
    # Test that we allow point evaluation that are slightly outside
    bb_tree = cpp.geometry.BoundingBoxTree(mesh, mesh.geometry.dim)
    u0 = Function(R)
    u0.vector().set(1.0)
    a = Vertex(mesh, 0).point().array()
    offset = 0.99 * np.finfo(float).eps

    a_shift_x = Point(a[0] - offset, a[1], a[2]).array()
    assert round(u0(a, bb_tree)[0] - u0(a_shift_x, bb_tree)[0], 7) == 0

    a_shift_xyz = Point(a[0] - offset / math.sqrt(3),
                        a[1] - offset / math.sqrt(3),
                        a[2] - offset / math.sqrt(3)).array()
    assert round(u0(a, bb_tree)[0] - u0(a_shift_xyz, bb_tree)[0], 7) == 0
Пример #9
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def test_Assign(mesh, f):
    """Assign value of mesh function."""
    f = f
    f[3] = 10
    v = Vertex(mesh, 3)
    assert f[v] == 10
Пример #10
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def myassemble(mesh):
    # Define basis functions and their gradients on the reference elements.
    def phi0(x):
        return 1.0 - x[0] - x[1]

    def phi1(x):
        return x[0]

    def phi2(x):
        return x[1]

    def f(x):
        return 1.0

    phi = [phi0, phi1, phi2]
    dphi = np.array(([-1.0, -1.0], [1.0, 0.0], [0.0, 1.0]))

    # Define quadrature points
    midpoints = np.array(([0.5, 0.0], [0.5, 0.5], [0.0, 0.5]))

    N = mesh.num_vertices()

    A = np.zeros((N, N))

    b = np.zeros((N, 1))

    # Used to hold cell vertices
    coord = np.zeros([3, 2])

    # Iterate over all cells, adding integral contribution to matrix/vector
    for c in cells(mesh):

        # Extract node numbers and vertex coordinates
        nodes = c.entities(0).astype('int')
        for i in range(0, 3):
            v = Vertex(mesh, int(nodes[i]))
            for j in range(0, 2):
                coord[i][j] = v.point()[j]

        # Compute Jacobian of map and area of cell
        J = np.outer(coord[0, :], dphi[0]) + \
            np.outer(coord[1, :], dphi[1]) + \
            np.outer(coord[2, :], dphi[2])
        dx = 0.5 * abs(np.linalg.det(J))

        # Iterate over quadrature points
        for p in midpoints:
            # Map p to physical cell
            x = coord[0, :] * phi[0](p) + \
                coord[1, :] * phi[1](p) + \
                coord[2, :] * phi[2](p)

            # Iterate over test functions
            for i in range(0, 3):
                v = phi[i](p)
                dv = np.linalg.solve(J.transpose(), dphi[i])

                # Assemble vector (linear form)
                integral = f(x)*v*dx / 3.0
                b[nodes[i]] += integral

                # Iterate over trial functions
                for j in range(0, 3):
                    u = phi[j](p)
                    du = np.linalg.solve(J.transpose(), dphi[j])

                    # Assemble matrix (bilinear form)
                    integral = (np.inner(du, dv)) * dx / 3.0
                    integral += u * v * dx / 3.0
                    A[nodes[i], nodes[j]] += integral

    return A, b
Пример #11
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def test_Assign(f, cube):
    f = f
    f[3] = 10
    v = Vertex(cube, 3)
    assert f[v] == 10
Пример #12
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def as_Vertex(mesh_entity):
    return Vertex(mesh_entity.mesh(), mesh_entity.index())
Пример #13
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def edge_to_vector(edge):
    v0, v1 = edge.entities(0)
    mesh = edge.mesh()
    v0 = Vertex(mesh, v0)
    v1 = Vertex(mesh, v1)
    return point_to_array(v1.point() - v0.point())