def Jhat(val):
     cell_params[param_name].assign(val)
     ics = Function(project(model.initial_conditions(), solver.VS),
                    name="ics")
     self._run(solver, ics)
     (vs_, vs) = solver.solution_fields()
     return assemble(form(vs))
Example #2
0
def main(N, dt, T, theta):

    if dolfin_adjoint:
        adj_reset()

    # Create cardiac model
    mesh = UnitSquareMesh(N, N)
    time = Constant(0.0)
    cell_model = NoCellModel()
    ac_str = "cos(t)*cos(2*pi*x[0])*cos(2*pi*x[1]) + 4*pow(pi, 2)*cos(2*pi*x[0])*cos(2*pi*x[1])*sin(t)"
    stimulus = Expression(ac_str, t=time, degree=3)
    heart = CardiacModel(mesh, time, 1.0, 1.0, cell_model, stimulus=stimulus)

    # Set-up solver
    ps = BasicSplittingSolver.default_parameters()
    ps["theta"] = theta
    ps["BasicBidomainSolver"]["linear_variational_solver"][
        "linear_solver"] = "direct"
    solver = BasicSplittingSolver(heart, params=ps)

    # Define exact solution (Note: v is returned at end of time
    # interval(s), u is computed at somewhere in the time interval
    # depending on theta)
    v_exact = Expression("cos(2*pi*x[0])*cos(2*pi*x[1])*sin(t)", t=T, degree=3)
    u_exact = Expression("-cos(2*pi*x[0])*cos(2*pi*x[1])*sin(t)/2.0",
                         t=T - (1 - theta) * dt,
                         degree=3)

    # Define initial condition(s)
    vs0 = Function(solver.VS)
    (vs_, vs, vur) = solver.solution_fields()
    vs_.assign(vs0)

    # Solve
    solutions = solver.solve((0, T), dt)
    for (timestep, (vs_, vs, vur)) in solutions:
        continue

    # Compute errors
    (v, s) = vs.split(deepcopy=True)
    v_error = errornorm(v_exact, v, "L2", degree_rise=2)
    (v, u, r) = vur.split(deepcopy=True)
    u_error = errornorm(u_exact, u, "L2", degree_rise=2)

    return (v_error, u_error, mesh.hmin(), dt, T)
    def tlm_adj_setup_cellmodel_parameters(self, cell_model, Scheme):
        mesh = UnitIntervalMesh(3)
        Model = cell_model.__class__

        # Initiate solver, with model and Scheme
        cell_params = Model.default_parameters()
        param_name = cellmodel_parameters_seeds[Model][0]
        cell_params[param_name] = Constant(cell_params[param_name],
                                           name=param_name)
        model = Model(params=cell_params)

        solver = self._setup_solver(model, Scheme, mesh)

        info_green("Running forward %s with %s (setup)" % (model, Scheme))
        ics = Function(project(model.initial_conditions(), solver.VS),
                       name="ics")
        self._run(solver, ics)

        # Define functional
        (vs_, vs) = solver.solution_fields()
        form = lambda w: inner(w, w) * dx
        J = Functional(form(vs) * dt[FINISH_TIME])

        # Compute value of functional with current ics
        Jics = assemble(form(vs))

        # Set-up runner
        def Jhat(val):
            cell_params[param_name].assign(val)
            ics = Function(project(model.initial_conditions(), solver.VS),
                           name="ics")
            self._run(solver, ics)
            (vs_, vs) = solver.solution_fields()
            return assemble(form(vs))

        # Stop annotating
        solver.parameters["enable_adjoint"] = False

        m = ConstantControl(cell_params[param_name])
        return J, Jhat, m, Jics