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UniformRefinementEstimator

UniformRefinementEstimator

Section: C Library Functions (3) Updated: Thu Apr 7 2011
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NAME

UniformRefinementEstimator -  

SYNOPSIS


#include <uniform_refinement_estimator.h>

Inherits ErrorEstimator.  

Public Types


typedef std::map< std::pair< const System *, unsigned int >, ErrorVector * > ErrorMap
 

Public Member Functions


UniformRefinementEstimator ()

~UniformRefinementEstimator ()

virtual void estimate_error (const System &system, ErrorVector &error_per_cell, const NumericVector< Number > *solution_vector=NULL, bool estimate_parent_error=false)

virtual void estimate_errors (const EquationSystems &equation_systems, ErrorVector &error_per_cell, const std::map< const System *, SystemNorm > &error_norms, const std::map< const System *, const NumericVector< Number > * > *solution_vectors=NULL, bool estimate_parent_error=false)

virtual void estimate_errors (const EquationSystems &equation_systems, ErrorMap &errors_per_cell, const std::map< const System *, const NumericVector< Number > * > *solution_vectors=NULL, bool estimate_parent_error=false)
 

Public Attributes


unsigned char number_h_refinements

unsigned char number_p_refinements

SystemNorm error_norm
 

Protected Member Functions


virtual void _estimate_error (const EquationSystems *equation_systems, const System *system, ErrorVector *error_per_cell, std::map< std::pair< const System *, unsigned int >, ErrorVector * > *errors_per_cell, const std::map< const System *, SystemNorm > *error_norms, const std::map< const System *, const NumericVector< Number > * > *solution_vectors=NULL, bool estimate_parent_error=false)

void reduce_error (std::vector< float > &error_per_cell) const
 

Detailed Description

This class implements a ``brute force'' error estimator which integrates differences between the current solution and the solution on a uniformly refined (in h and/or p, for an arbitrary number of levels) grid.

Author:

Roy H. Stogner, 2006.

Definition at line 42 of file uniform_refinement_estimator.h.  

Member Typedef Documentation

 

typedef std::map<std::pair<const System*, unsigned int>, ErrorVector*> ErrorEstimator::ErrorMap [inherited]When calculating many error vectors at once, we need a data structure to hold them all

Definition at line 105 of file error_estimator.h.  

Constructor & Destructor Documentation

 

UniformRefinementEstimator::UniformRefinementEstimator () [inline]Constructor. Sets the most common default parameter values.

Definition at line 49 of file uniform_refinement_estimator.h.

References ErrorEstimator::error_norm, and libMeshEnums::H1.

                               : number_h_refinements(1),
                                 number_p_refinements(0)
  { error_norm = H1; }
 

UniformRefinementEstimator::~UniformRefinementEstimator () [inline]Destructor.

Definition at line 56 of file uniform_refinement_estimator.h.

{}
 

Member Function Documentation

 

void UniformRefinementEstimator::_estimate_error (const EquationSystems *equation_systems, const System *system, ErrorVector *error_per_cell, std::map< std::pair< const System *, unsigned int >, ErrorVector * > *errors_per_cell, const std::map< const System *, SystemNorm > *error_norms, const std::map< const System *, const NumericVector< Number > * > *solution_vectors = NULL, boolestimate_parent_error = false) [protected, virtual]The code for estimate_error and both estimate_errors versions is very similar, so we use the same function for all three

Definition at line 82 of file uniform_refinement_estimator.C.

References MeshBase::active_local_elements_begin(), MeshBase::active_local_elements_end(), EquationSystems::adjoint_solve(), FEBase::build(), NumericVector< T >::clear(), System::current_local_solution, System::current_solution(), FEType::default_quadrature_rule(), DofMap::dof_indices(), ErrorEstimator::error_norm, AutoPtr< Tp >::get(), System::get_dof_map(), System::get_equation_systems(), EquationSystems::get_mesh(), DofMap::get_send_list(), EquationSystems::get_system(), System::get_vector(), libMeshEnums::H1, libMeshEnums::H1_SEMINORM, libMeshEnums::H2, libMeshEnums::H2_SEMINORM, DofObject::id(), NumericVector< T >::init(), libMeshEnums::L2, libmesh_norm(), MeshBase::max_elem_id(), MeshBase::mesh_dimension(), MeshBase::n_elem(), EquationSystems::n_systems(), System::n_vars(), number_h_refinements, number_p_refinements, Elem::parent(), MeshBase::partitioner(), System::project_solution_on_reinit(), ErrorEstimator::reduce_error(), EquationSystems::reinit(), AutoPtr< Tp >::release(), AutoPtr< Tp >::reset(), libMeshEnums::SERIAL, TypeTensor< T >::size_sq(), TypeVector< T >::size_sq(), System::solution, EquationSystems::solve(), NumericVector< T >::swap(), SystemNorm::type(), MeshRefinement::uniformly_coarsen(), MeshRefinement::uniformly_p_coarsen(), MeshRefinement::uniformly_p_refine(), MeshRefinement::uniformly_refine(), System::update(), DofMap::variable_type(), System::vectors_begin(), System::vectors_end(), and SystemNorm::weight_sq().

Referenced by estimate_error(), and estimate_errors().

{
  // Get a vector of the Systems we're going to work on,
  // and set up a error_norms map if necessary
  std::vector<System *> system_list;
  AutoPtr<std::map<const System*, SystemNorm > > error_norms = 
    AutoPtr<std::map<const System*, SystemNorm > >
    (new std::map<const System*, SystemNorm>);

  if (_es)
    {
      libmesh_assert(!_system);
      libmesh_assert(_es->n_systems());
      _system = &(_es->get_system(0));
      libmesh_assert(&(_system->get_equation_systems()) == _es);

      libmesh_assert(_es->n_systems());
      for (unsigned int i=0; i != _es->n_systems(); ++i)
      // We have to break the rules here, because we can't refine a const System
        system_list.push_back(const_cast<System *>(&(_es->get_system(i))));

      // If we're computing one vector, we need to know how to scale
      // each variable's contributions to it.
      if (_error_norms)
        {
          libmesh_assert(!errors_per_cell);
        }
      else
      // If we're computing many vectors, we just need to know which
      // variables to skip
        {
          libmesh_assert (errors_per_cell);

          _error_norms = error_norms.get();

          for (unsigned int i=0; i!= _es->n_systems(); ++i)
            {
              const System &sys = _es->get_system(i);
              unsigned int n_vars = sys.n_vars();

              std::vector<Real> weights(n_vars, 0.0);
              for (unsigned int v = 0; v != n_vars; ++v)
                {
                  if (errors_per_cell->find(std::make_pair(&sys, v)) ==
                      errors_per_cell->end())
                    continue;

                  weights[v] = 1.0;
                }
              (*error_norms)[&sys] =
                SystemNorm(std::vector<FEMNormType>(n_vars, error_norm.type(0)),
                           weights);
            }
        }
    }
  else
    {
      libmesh_assert(_system);
      // We have to break the rules here, because we can't refine a const System
      system_list.push_back(const_cast<System *>(_system));

      libmesh_assert(!_error_norms);
      (*error_norms)[_system] = error_norm;
      _error_norms = error_norms.get();
    }

  // An EquationSystems reference will be convenient.
  // We have to break the rules here, because we can't refine a const System
  EquationSystems& es =
    const_cast<EquationSystems &>(_system->get_equation_systems());

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

  // The dimensionality of the mesh
  const unsigned int dim = mesh.mesh_dimension();
  
  // Resize the error_per_cell vectors to be
  // the number of elements, initialize them to 0.
  if (error_per_cell)
    {
      error_per_cell->clear();
      error_per_cell->resize (mesh.max_elem_id(), 0.);
    }
  else
    {
      libmesh_assert(errors_per_cell);
      for (ErrorMap::iterator i = errors_per_cell->begin();
           i != errors_per_cell->end(); ++i)
        {
          ErrorVector *e = i->second;
          e->clear();
          e->resize(mesh.max_elem_id(), 0.);
        }
    }

  // We'll want to back up all coarse grid vectors
  std::vector<std::map<std::string, NumericVector<Number> *> >
    coarse_vectors(system_list.size());
  std::vector<NumericVector<Number> *>
    coarse_solutions(system_list.size());
  std::vector<NumericVector<Number> *>
    coarse_local_solutions(system_list.size());
  // And make copies of projected solutions
  std::vector<NumericVector<Number> *>
    projected_solutions(system_list.size());

  // And we'll need to temporarily change solution projection settings
  std::vector<bool> old_projection_settings(system_list.size());

  // And it'll be best to avoid any repartitioning
  AutoPtr<Partitioner> old_partitioner = mesh.partitioner();
  mesh.partitioner().reset(NULL);

  for (unsigned int i=0; i != system_list.size(); ++i)
    {
      System &system = *system_list[i];

      // Check for valid error_norms
      libmesh_assert (_error_norms->find(&system) !=
                      _error_norms->end());

      // Back up the solution vector
      coarse_solutions[i] = system.solution->clone().release();
      coarse_local_solutions[i] =
        system.current_local_solution->clone().release();

      // Back up all other coarse grid 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[i][var_name] = vec->second->clone().release();
        }

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

      // Make sure the solution is projected when we refine the mesh
      old_projection_settings[i] = system.project_solution_on_reinit();
      system.project_solution_on_reinit() = true;
    }

  // Find the number of coarse mesh elements, to make it possible
  // to find correct coarse elem ids later
  const unsigned int max_coarse_elem_id = mesh.max_elem_id();
#ifndef NDEBUG
  // n_coarse_elem is only used in an assertion later so
  // avoid declaring it unless asserts are active.
  const unsigned int n_coarse_elem = mesh.n_elem();
#endif
  
  // Uniformly refine the mesh
  MeshRefinement mesh_refinement(mesh);

  libmesh_assert (number_h_refinements > 0 || number_p_refinements > 0);

  // FIXME: this may break if there is more than one System
  // on this mesh but estimate_error was still called instead of
  // estimate_errors
  for (unsigned int i = 0; i != number_h_refinements; ++i)
    {
      mesh_refinement.uniformly_refine(1);
      es.reinit();
    }
      
  for (unsigned int i = 0; i != number_p_refinements; ++i)
    {
      mesh_refinement.uniformly_p_refine(1);
      es.reinit();
    }

  for (unsigned int i=0; i != system_list.size(); ++i)
    {
      System &system = *system_list[i];
      
      // Copy the projected coarse grid solutions, which will be
      // overwritten by solve()
//      projected_solutions[i] = system.solution->clone().release();
      projected_solutions[i] = NumericVector<Number>::build().release();
      projected_solutions[i]->init(system.solution->size(), true, SERIAL);
      system.solution->localize(*projected_solutions[i],
                                system.get_dof_map().get_send_list());
    }

  // Get the uniformly refined solution.

  if (_es)
    {
      // No specified vectors == forward solve
      if (!solution_vectors)
        es.solve();
      else
        {
          libmesh_assert(solution_vectors->size() == es.n_systems());
          libmesh_assert(solution_vectors->find(system_list[0]) !=
                         solution_vectors->end());
          const bool solve_adjoint = 
            (system_list[0]->have_vector('adjoint_solution') &&
             (solution_vectors->find(system_list[0])->second ==
              &system_list[0]->get_adjoint_solution()));
          libmesh_assert(solve_adjoint ||
            (solution_vectors->find(system_list[0])->second ==
             system_list[0]->solution.get()) ||
             !solution_vectors->find(system_list[0])->second);
                         
#ifdef DEBUG
          for (unsigned int i=0; i != system_list.size(); ++i)
            {
              libmesh_assert(solution_vectors->find(system_list[i]) !=
                             solution_vectors->end());
              libmesh_assert(!solve_adjoint ||
                             solution_vectors->find(system_list[i])->second ==
                             &system_list[i]->get_adjoint_solution());
              libmesh_assert(solve_adjoint ||
                             solution_vectors->find(system_list[i])->second ==
                             system_list[i]->solution.get() ||
                             !solution_vectors->find(system_list[i])->second);
            }
#endif

          if (solve_adjoint)
            {
              // Set up proper initial guesses
              for (unsigned int i=0; i != system_list.size(); ++i)
                system_list[i]->get_adjoint_solution() = *system_list[i]->solution;
              es.adjoint_solve();
              // Put the adjoint_solution into solution for
              // comparisons
              for (unsigned int i=0; i != system_list.size(); ++i)
                {
                  system_list[i]->get_adjoint_solution().swap(*system_list[i]->solution);
                  system_list[i]->update();
                }
            }
          else
            es.solve();
        }
    }
  else
    {
      // No specified vectors == forward solve
      if (!solution_vectors)
        system_list[0]->solve();
      else
        {
          libmesh_assert(solution_vectors->find(system_list[0]) !=
                         solution_vectors->end());

          const bool solve_adjoint = 
            (system_list[0]->have_vector('adjoint_solution') &&
             (solution_vectors->find(system_list[0])->second ==
              &system_list[0]->get_adjoint_solution()));
          libmesh_assert(solve_adjoint ||
            (solution_vectors->find(system_list[0])->second ==
             system_list[0]->solution.get()) ||
            !solution_vectors->find(system_list[0])->second);

          if (solve_adjoint)
            {
              // Set up proper initial guesses
              for (unsigned int i=0; i != system_list.size(); ++i)
                system_list[0]->get_adjoint_solution() = *system_list[0]->solution;
              system_list[0]->adjoint_solve();
              // Put the adjoint_solution into solution for
              // comparisons
              system_list[0]->get_adjoint_solution().swap(*system_list[0]->solution);
              system_list[0]->update();
            }
          else
            system_list[0]->solve();
        }
    }
  
  // Get the error in the uniformly refined solution(s).

  for (unsigned int i=0; i != system_list.size(); ++i)
    {
      System &system = *system_list[i];

      unsigned int n_vars = system.n_vars();

      DofMap &dof_map = system.get_dof_map();

      const SystemNorm &system_i_norm =
        _error_norms->find(&system)->second;

      NumericVector<Number> *projected_solution = projected_solutions[i];

      // Loop over all the variables in the system
      for (unsigned int var=0; var<n_vars; var++)
        {
          // Get the error vector to fill for this system and variable
          ErrorVector *err_vec = error_per_cell;
          if (!err_vec)
            {
              libmesh_assert(errors_per_cell);
              err_vec =
                (*errors_per_cell)[std::make_pair(&system,var)];
            }

          // The type of finite element to use for this variable
          const FEType& fe_type = dof_map.variable_type (var);
      
          // Finite element object for each fine element
          AutoPtr<FEBase> fe (FEBase::build (dim, fe_type));

          // Build and attach an appropriate quadrature rule
          AutoPtr<QBase> qrule = fe_type.default_quadrature_rule(dim);
          fe->attach_quadrature_rule (qrule.get());
      
          const std::vector<Real>&  JxW = fe->get_JxW();
          const std::vector<std::vector<Real> >& phi = fe->get_phi();
          const std::vector<std::vector<RealGradient> >& dphi =
            fe->get_dphi();
#ifdef LIBMESH_ENABLE_SECOND_DERIVATIVES
          const std::vector<std::vector<RealTensor> >& d2phi =
            fe->get_d2phi();
#endif

          // The global DOF indices for the fine element
          std::vector<unsigned int> dof_indices;
      
          // Iterate over all the active elements in the fine mesh
          // that live on this processor.
          MeshBase::const_element_iterator       elem_it  = mesh.active_local_elements_begin();
          const MeshBase::const_element_iterator elem_end = mesh.active_local_elements_end(); 

          for (; elem_it != elem_end; ++elem_it)
            {
              // e is necessarily an active element on the local processor
              const Elem* elem = *elem_it;

              // Find the element id for the corresponding coarse grid element
              const Elem* coarse = elem;
              unsigned int e_id = coarse->id();
              while (e_id >= max_coarse_elem_id)
                {
                  libmesh_assert (coarse->parent());
                  coarse = coarse->parent();
                  e_id = coarse->id();
                }
          
              double L2normsq = 0., H1seminormsq = 0., H2seminormsq = 0.;

              // reinitialize the element-specific data
              // for the current element
              fe->reinit (elem);

              // Get the local to global degree of freedom maps
              dof_map.dof_indices (elem, dof_indices, var);

              // The number of quadrature points
              const unsigned int n_qp = qrule->n_points();

              // The number of shape functions
              const unsigned int n_sf = dof_indices.size();

              //
              // Begin the loop over the Quadrature points.
              //
              for (unsigned int qp=0; qp<n_qp; qp++)
                {
                  Number u_fine = 0., u_coarse = 0.;

                  Gradient grad_u_fine, grad_u_coarse;
#ifdef LIBMESH_ENABLE_SECOND_DERIVATIVES
                  Tensor grad2_u_fine, grad2_u_coarse;
#endif

                  // Compute solution values at the current
                  // quadrature point.  This reqiures a sum
                  // over all the shape functions evaluated
                  // at the quadrature point.
                  for (unsigned int i=0; i<n_sf; i++)
                    {
                      u_fine            += phi[i][qp]*system.current_solution (dof_indices[i]);
                      u_coarse          += phi[i][qp]*(*projected_solution) (dof_indices[i]);
                      grad_u_fine       += dphi[i][qp]*system.current_solution (dof_indices[i]);
                      grad_u_coarse     += dphi[i][qp]*(*projected_solution) (dof_indices[i]);
#ifdef LIBMESH_ENABLE_SECOND_DERIVATIVES
                      grad2_u_fine      += d2phi[i][qp]*system.current_solution (dof_indices[i]);
                      grad2_u_coarse    += d2phi[i][qp]*(*projected_solution) (dof_indices[i]);
#endif
                    }

                  // Compute the value of the error at this quadrature point
                  const Number val_error = u_fine - u_coarse;

                  // Add the squares of the error to each contribution
                  if (system_i_norm.type(var) == L2 ||
                      system_i_norm.type(var) == H1 ||
                      system_i_norm.type(var) == H2)
                    {
                      L2normsq += JxW[qp] * system_i_norm.weight_sq(var) *
                                  libmesh_norm(val_error);
                      libmesh_assert (L2normsq     >= 0.);
                    }


                  // Compute the value of the error in the gradient at this
                  // quadrature point
                  if (system_i_norm.type(var) == H1 ||
                      system_i_norm.type(var) == H2 ||
                      system_i_norm.type(var) == H1_SEMINORM)
                    {
                      Gradient grad_error = grad_u_fine - grad_u_coarse;

                      H1seminormsq += JxW[qp] * system_i_norm.weight_sq(var) *
                        grad_error.size_sq();
                      libmesh_assert (H1seminormsq >= 0.);
                    }

#ifdef LIBMESH_ENABLE_SECOND_DERIVATIVES
                  // Compute the value of the error in the hessian at this
                  // quadrature point
                  if (system_i_norm.type(var) == H2 ||
                      system_i_norm.type(var) == H2_SEMINORM)
                    {
                      Tensor grad2_error = grad2_u_fine - grad2_u_coarse;

                      H2seminormsq += JxW[qp] * system_i_norm.weight_sq(var) *
                        grad2_error.size_sq();
                      libmesh_assert (H2seminormsq >= 0.);
                    }
#endif
                } // end qp loop

              if (system_i_norm.type(var) == L2 ||
                  system_i_norm.type(var) == H1 ||
                  system_i_norm.type(var) == H2)
                (*err_vec)[e_id] += L2normsq;
              if (system_i_norm.type(var) == H1 ||
                  system_i_norm.type(var) == H2 ||
                  system_i_norm.type(var) == H1_SEMINORM)
                (*err_vec)[e_id] += H1seminormsq;
              
              if (system_i_norm.type(var) == H2 ||
                  system_i_norm.type(var) == H2_SEMINORM)
                (*err_vec)[e_id] += H2seminormsq;
            } // End loop over active local elements
        } // End loop over variables

      // Don't bother projecting the solution; we'll restore from backup
      // after coarsening
      system.project_solution_on_reinit() = false;
    }


  // Uniformly coarsen the mesh, without projecting the solution
  libmesh_assert (number_h_refinements > 0 || number_p_refinements > 0);

  for (unsigned int i = 0; i != number_h_refinements; ++i)
    {
      mesh_refinement.uniformly_coarsen(1);
      // FIXME - should the reinits here be necessary? - RHS
      es.reinit();
    }
      
  for (unsigned int i = 0; i != number_p_refinements; ++i)
    {
      mesh_refinement.uniformly_p_coarsen(1);
      es.reinit();
    }

  // We should be back where we started
  libmesh_assert(n_coarse_elem == mesh.n_elem());

  // Each processor has now computed the error contribuions
  // for its local elements.  We need to sum the vector
  // and then take the square-root of each component.  Note
  // that we only need to sum if we are running on multiple
  // processors, and we only need to take the square-root
  // if the value is nonzero.  There will in general be many
  // zeros for the inactive elements.

  if (error_per_cell)
    {
      // First sum the vector of estimated error values
      this->reduce_error(*error_per_cell);

      // Compute the square-root of each component.
      START_LOG('std::sqrt()', 'UniformRefinementEstimator');
      for (unsigned int i=0; i<error_per_cell->size(); i++)
        if ((*error_per_cell)[i] != 0.)
          (*error_per_cell)[i] = std::sqrt((*error_per_cell)[i]);
      STOP_LOG('std::sqrt()', 'UniformRefinementEstimator');
    }
  else
    {
      for (ErrorMap::iterator i = errors_per_cell->begin();
           i != errors_per_cell->end(); ++i)
        {
          ErrorVector *e = i->second;
          // First sum the vector of estimated error values
          this->reduce_error(*e);

          // Compute the square-root of each component.
          START_LOG('std::sqrt()', 'UniformRefinementEstimator');
          for (unsigned int i=0; i<e->size(); i++)
            if ((*e)[i] != 0.)
              (*e)[i] = std::sqrt((*e)[i]);
          STOP_LOG('std::sqrt()', 'UniformRefinementEstimator');
        }
    }

  // Restore old solutions and clean up the heap
  for (unsigned int i=0; i != system_list.size(); ++i)
    {
      System &system = *system_list[i];

      system.project_solution_on_reinit() = old_projection_settings[i];
  
      // Restore the coarse solution vectors and delete their copies
      *system.solution = *coarse_solutions[i];
      delete coarse_solutions[i];
      *system.current_local_solution = *coarse_local_solutions[i];
      delete coarse_local_solutions[i];
      delete projected_solutions[i];

      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;

          system.get_vector(var_name) = *coarse_vectors[i][var_name];

          coarse_vectors[i][var_name]->clear();
          delete coarse_vectors[i][var_name];
        }
    }

  // Restore old partitioner settings
  mesh.partitioner() = old_partitioner;
}
 

void UniformRefinementEstimator::estimate_error (const System &system, ErrorVector &error_per_cell, const NumericVector< Number > *solution_vector = NULL, boolestimate_parent_error = false) [virtual]This function does uniform refinements and a solve to get an improved solution on each cell, then estimates the error by integrating differences between the coarse and fine solutions.

system.solve() must be called, and so should have no side effects.

Only the provided system is solved on the refined mesh; for problems decoupled into multiple systems, use of estimate_errors() should be more reliable.

The estimated error is output in the vector error_per_cell

Implements ErrorEstimator.

Definition at line 45 of file uniform_refinement_estimator.C.

References _estimate_error().

{
  START_LOG('estimate_error()', 'UniformRefinementEstimator');
  std::map<const System*, const NumericVector<Number>* > solution_vectors;
  solution_vectors[&_system] = solution_vector;
  this->_estimate_error (NULL, &_system, &error_per_cell, NULL, NULL,
                         &solution_vectors, estimate_parent_error);
  STOP_LOG('estimate_error()', 'UniformRefinementEstimator');
}
 

void UniformRefinementEstimator::estimate_errors (const EquationSystems &equation_systems, ErrorVector &error_per_cell, const std::map< const System *, SystemNorm > &error_norms, const std::map< const System *, const NumericVector< Number > * > *solution_vectors = NULL, boolestimate_parent_error = false) [virtual]Currently this function ignores the error_norm member variable, and uses the function argument error_norms instead.

This function is named estimate_errors instead of estimate_error because otherwise C++ can get confused.

Reimplemented from ErrorEstimator.

Definition at line 58 of file uniform_refinement_estimator.C.

References _estimate_error().

{
  START_LOG('estimate_errors()', 'UniformRefinementEstimator');
  this->_estimate_error (&_es, NULL, &error_per_cell, NULL,
                         &error_norms, solution_vectors,
                         estimate_parent_error);
  STOP_LOG('estimate_errors()', 'UniformRefinementEstimator');
}
 

void UniformRefinementEstimator::estimate_errors (const EquationSystems &equation_systems, ErrorMap &errors_per_cell, const std::map< const System *, const NumericVector< Number > * > *solution_vectors = NULL, boolestimate_parent_error = false) [virtual]Currently this function ignores the component_scale member variable, because it calculates each error individually, unscaled.

The user selects which errors get computed by filling a map with error vectors: If errors_per_cell[&system][v] exists, it will be filled with the error values in variable v of system

Reimplemented from ErrorEstimator.

Definition at line 71 of file uniform_refinement_estimator.C.

References _estimate_error().

{
  START_LOG('estimate_errors()', 'UniformRefinementEstimator');
  this->_estimate_error (&_es, NULL, NULL, &errors_per_cell, NULL,
                         solution_vectors, estimate_parent_error);
  STOP_LOG('estimate_errors()', 'UniformRefinementEstimator');
}
 

void ErrorEstimator::reduce_error (std::vector< float > &error_per_cell) const [protected, inherited]This method takes the local error contributions in error_per_cell from each processor and combines them to get the global error vector.

Definition at line 32 of file error_estimator.C.

Referenced by _estimate_error(), PatchRecoveryErrorEstimator::estimate_error(), and JumpErrorEstimator::estimate_error().

{
  // This function must be run on all processors at once
  parallel_only();

  // Each processor has now computed the error contribuions
  // for its local elements.  We may need to sum the vector to
  // recover the error for each element.
  
  Parallel::sum(error_per_cell);
}
 

Member Data Documentation

 

SystemNorm ErrorEstimator::error_norm [inherited]When estimating the error in a single system, the error_norm is used to control the scaling and norm choice for each variable. Not all estimators will support all norm choices. The default scaling is for all variables to be weighted equally. The default norm choice depends on the error estimator.

Part of this functionality was supported via component_scale and sobolev_order in older libMesh versions, and a small part was supported via component_mask in even older versions. Hopefully the encapsulation here will allow us to avoid changing this API again.

Definition at line 137 of file error_estimator.h.

Referenced by _estimate_error(), KellyErrorEstimator::boundary_side_integration(), DiscontinuityMeasure::boundary_side_integration(), DiscontinuityMeasure::DiscontinuityMeasure(), JumpErrorEstimator::estimate_error(), ErrorEstimator::estimate_errors(), ExactErrorEstimator::ExactErrorEstimator(), ExactErrorEstimator::find_squared_element_error(), KellyErrorEstimator::internal_side_integration(), LaplacianErrorEstimator::internal_side_integration(), DiscontinuityMeasure::internal_side_integration(), KellyErrorEstimator::KellyErrorEstimator(), LaplacianErrorEstimator::LaplacianErrorEstimator(), PatchRecoveryErrorEstimator::EstimateError::operator()(), PatchRecoveryErrorEstimator::PatchRecoveryErrorEstimator(), and UniformRefinementEstimator().  

unsigned char UniformRefinementEstimator::number_h_refinementsHow many h refinements to perform to get the fine grid

Definition at line 109 of file uniform_refinement_estimator.h.

Referenced by _estimate_error().  

unsigned char UniformRefinementEstimator::number_p_refinementsHow many p refinements to perform to get the fine grid

Definition at line 114 of file uniform_refinement_estimator.h.

Referenced by _estimate_error().

 

Author

Generated automatically by Doxygen for libMesh from the source code.


 

Index

NAME
SYNOPSIS
Public Types
Public Member Functions
Public Attributes
Protected Member Functions
Detailed Description
Member Typedef Documentation
typedef std::map<std::pair<const System*, unsigned int>, ErrorVector*> ErrorEstimator::ErrorMap [inherited]When calculating many error vectors at once, we need a data structure to hold them all
Constructor & Destructor Documentation
UniformRefinementEstimator::UniformRefinementEstimator () [inline]Constructor. Sets the most common default parameter values.
UniformRefinementEstimator::~UniformRefinementEstimator () [inline]Destructor.
Member Function Documentation
void UniformRefinementEstimator::_estimate_error (const EquationSystems *equation_systems, const System *system, ErrorVector *error_per_cell, std::map< std::pair< const System *, unsigned int >, ErrorVector * > *errors_per_cell, const std::map< const System *, SystemNorm > *error_norms, const std::map< const System *, const NumericVector< Number > * > *solution_vectors = NULL, boolestimate_parent_error = false) [protected, virtual]The code for estimate_error and both estimate_errors versions is very similar, so we use the same function for all three
void UniformRefinementEstimator::estimate_error (const System &system, ErrorVector &error_per_cell, const NumericVector< Number > *solution_vector = NULL, boolestimate_parent_error = false) [virtual]This function does uniform refinements and a solve to get an improved solution on each cell, then estimates the error by integrating differences between the coarse and fine solutions.
void UniformRefinementEstimator::estimate_errors (const EquationSystems &equation_systems, ErrorVector &error_per_cell, const std::map< const System *, SystemNorm > &error_norms, const std::map< const System *, const NumericVector< Number > * > *solution_vectors = NULL, boolestimate_parent_error = false) [virtual]Currently this function ignores the error_norm member variable, and uses the function argument error_norms instead.
void UniformRefinementEstimator::estimate_errors (const EquationSystems &equation_systems, ErrorMap &errors_per_cell, const std::map< const System *, const NumericVector< Number > * > *solution_vectors = NULL, boolestimate_parent_error = false) [virtual]Currently this function ignores the component_scale member variable, because it calculates each error individually, unscaled.
void ErrorEstimator::reduce_error (std::vector< float > &error_per_cell) const [protected, inherited]This method takes the local error contributions in error_per_cell from each processor and combines them to get the global error vector.
Member Data Documentation
SystemNorm ErrorEstimator::error_norm [inherited]When estimating the error in a single system, the error_norm is used to control the scaling and norm choice for each variable. Not all estimators will support all norm choices. The default scaling is for all variables to be weighted equally. The default norm choice depends on the error estimator.
unsigned char UniformRefinementEstimator::number_h_refinementsHow many h refinements to perform to get the fine grid
unsigned char UniformRefinementEstimator::number_p_refinementsHow many p refinements to perform to get the fine grid
Author

This document was created by man2html, using the manual pages.
Time: 21:57:56 GMT, April 16, 2011