def test_expr():
from ufl import triangle, FiniteElement, TestFunction, TrialFunction, Coefficient
element = FiniteElement("CG", triangle, 1)
v = TestFunction(element)
u = TrialFunction(element)
f = Coefficient(element)
g = Coefficient(element)
expr = (f + g) * u.dx(0) * (g - 1) * v
return expr
def test_expr():
from ufl import triangle, FiniteElement, TestFunction, TrialFunction, Coefficient
element = FiniteElement("CG", triangle, 1)
v = TestFunction(element)
u = TrialFunction(element)
f = Coefficient(element)
g = Coefficient(element)
expr = (f+g)*u.dx(0)*(g-1)*v
return expr
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with UFL. If not, see <http://www.gnu.org/licenses/>.
#
# First added: 2008-03-31
# Last changed: 2008-03-31
#
# The linearised bilinear form a(u,v) and linear form L(v) for
# the nonlinear equation - div (1+u) grad u = f (non-linear Poisson)
from ufl import (Coefficient, FiniteElement, TestFunction, TrialFunction,
VectorElement, dot, dx, grad, i, triangle)
element = FiniteElement("Lagrange", triangle, 2)
QE = FiniteElement("Quadrature", triangle, 2, quad_scheme="default")
sig = VectorElement("Quadrature", triangle, 1, quad_scheme="default")
v = TestFunction(element)
u = TrialFunction(element)
u0 = Coefficient(element)
C = Coefficient(QE)
sig0 = Coefficient(sig)
f = Coefficient(element)
a = v.dx(i) * C * u.dx(i) * dx(
metadata={"quadrature_degree": 2}) + v.dx(i) * 2 * u0 * u * u0.dx(i) * dx
L = v * f * dx - dot(grad(v), sig0) * dx(metadata={"quadrature_degree": 1})
