C++ ErrorVector::clear方法代码示例

void AdjointRefinementEstimator::estimate_error (const System & _system,
                                                 ErrorVector & error_per_cell,
                                                 const NumericVector<Number> * solution_vector,
                                                 bool /*estimate_parent_error*/)
{
  // We have to break the rules here, because we can't refine a const System
  System & system = const_cast<System &>(_system);

  // An EquationSystems reference will be convenient.
  EquationSystems & es = system.get_equation_systems();

  // The current mesh
  MeshBase & mesh = es.get_mesh();

  // Get coarse grid adjoint solutions.  This should be a relatively
  // quick (especially with preconditioner reuse) way to get a good
  // initial guess for the fine grid adjoint solutions.  More
  // importantly, subtracting off a coarse adjoint approximation gives
  // us better local error indication, and subtracting off *some* lift
  // function is necessary for correctness if we have heterogeneous
  // adjoint Dirichlet conditions.

  // Solve the adjoint problem(s) on the coarse FE space
  // Only if the user didn't already solve it for us
  if (!system.is_adjoint_already_solved())
    system.adjoint_solve(_qoi_set);

  // Loop over all the adjoint problems and, if any have heterogenous
  // Dirichlet conditions, get the corresponding coarse lift
  // function(s)
  for (unsigned int j=0; j != system.qoi.size(); j++)
    {
      // Skip this QoI if it is not in the QoI Set or if there are no
      // heterogeneous Dirichlet boundaries for it
      if (_qoi_set.has_index(j) &&
          system.get_dof_map().has_adjoint_dirichlet_boundaries(j))
        {
          std::ostringstream liftfunc_name;
          liftfunc_name << "adjoint_lift_function" << j;
          NumericVector<Number> & liftvec =
            system.add_vector(liftfunc_name.str());

          system.get_dof_map().enforce_constraints_exactly
            (system, &liftvec, true);
        }
    }

  // We'll want to back up all coarse grid vectors
  std::map<std::string, NumericVector<Number> *> coarse_vectors;
  for (System::vectors_iterator vec = system.vectors_begin(); vec !=
         system.vectors_end(); ++vec)
    {
      // The (string) name of this vector
      const std::string & var_name = vec->first;

      coarse_vectors[var_name] = vec->second->clone().release();
    }
  // Back up the coarse solution and coarse local solution
  NumericVector<Number> * coarse_solution =
    system.solution->clone().release();
  NumericVector<Number> * coarse_local_solution =
    system.current_local_solution->clone().release();

  // And we'll need to temporarily change solution projection settings
  bool old_projection_setting;
  old_projection_setting = system.project_solution_on_reinit();

  // Make sure the solution is projected when we refine the mesh
  system.project_solution_on_reinit() = true;

  // And it'll be best to avoid any repartitioning
  UniquePtr<Partitioner> old_partitioner(mesh.partitioner().release());

  // And we can't allow any renumbering
  const bool old_renumbering_setting = mesh.allow_renumbering();
  mesh.allow_renumbering(false);

  // Use a non-standard solution vector if necessary
  if (solution_vector && solution_vector != system.solution.get())
    {
      NumericVector<Number> * newsol =
        const_cast<NumericVector<Number> *> (solution_vector);
      newsol->swap(*system.solution);
      system.update();
    }

  // Resize the error_per_cell vector to be
  // the number of elements, initialized to 0.
  error_per_cell.clear();
  error_per_cell.resize (mesh.max_elem_id(), 0.);

#ifndef NDEBUG
  // n_coarse_elem is only used in an assertion later so
  // avoid declaring it unless asserts are active.
  const dof_id_type n_coarse_elem = mesh.n_elem();
#endif

  // Uniformly refine the mesh
  MeshRefinement mesh_refinement(mesh);

//.........这里部分代码省略.........