示例#1
0
文件: vtk_io.C 项目: ZJLi2013/libmesh
void VTKIO::read (const std::string& name)
{
  // This is a serial-only process for now;
  // the Mesh should be read on processor 0 and
  // broadcast later
  libmesh_assert_equal_to (MeshOutput<MeshBase>::mesh().processor_id(), 0);

  // Keep track of what kinds of elements this file contains
  elems_of_dimension.clear();
  elems_of_dimension.resize(4, false);

#ifndef LIBMESH_HAVE_VTK
  libMesh::err << "Cannot read VTK file: " << name
	        << "\nYou must have VTK installed and correctly configured to read VTK meshes."
	        << std::endl;
  libmesh_error();

#else
  // Use a typedef, because these names are just crazy
  typedef vtkSmartPointer<vtkXMLUnstructuredGridReader> MyReader;
  MyReader reader = MyReader::New();

  // Pass the filename along to the reader
  reader->SetFileName( name.c_str() );

  // Force reading
  reader->Update();

  // read in the grid
  _vtk_grid = reader->GetOutput();
  // _vtk_grid->Update(); // FIXME: Necessary?

  // Get a reference to the mesh
  MeshBase& mesh = MeshInput<MeshBase>::mesh();

  // Clear out any pre-existing data from the Mesh
  mesh.clear();

  // Get the number of points from the _vtk_grid object
  const unsigned int vtk_num_points = static_cast<unsigned int>(_vtk_grid->GetNumberOfPoints());

  // always numbered nicely??, so we can loop like this
  // I'm pretty sure it is numbered nicely
  for (unsigned int i=0; i<vtk_num_points; ++i)
    {
      // add to the id map
      // and add the actual point
      double * pnt = _vtk_grid->GetPoint(static_cast<vtkIdType>(i));
      Point xyz(pnt[0], pnt[1], pnt[2]);
      Node* newnode = mesh.add_point(xyz, i);

      // Add node to the nodes vector &
      // tell the MeshData object the foreign node id.
      if (this->_mesh_data != NULL)
	this->_mesh_data->add_foreign_node_id (newnode, i);
    }

  // Get the number of cells from the _vtk_grid object
  const unsigned int vtk_num_cells = static_cast<unsigned int>(_vtk_grid->GetNumberOfCells());

  for (unsigned int i=0; i<vtk_num_cells; ++i)
    {
      vtkCell* cell = _vtk_grid->GetCell(i);
      Elem* elem = NULL;
      switch (cell->GetCellType())
	{
        case VTK_LINE:
          elem = new Edge2;
          break;
        case VTK_QUADRATIC_EDGE:
          elem = new Edge3;
          break;
        case VTK_TRIANGLE:
          elem = new Tri3();
          break;
        case VTK_QUADRATIC_TRIANGLE:
          elem = new Tri6();
          break;
        case VTK_QUAD:
          elem = new Quad4();
          break;
        case VTK_QUADRATIC_QUAD:
          elem = new Quad8();
          break;
#if VTK_MAJOR_VERSION > 5 || (VTK_MAJOR_VERSION == 5 && VTK_MINOR_VERSION > 0)
        case VTK_BIQUADRATIC_QUAD:
          elem = new Quad9();
          break;
#endif
	case VTK_TETRA:
	  elem = new Tet4();
	  break;
        case VTK_QUADRATIC_TETRA:
	  elem = new Tet10();
	  break;
	case VTK_WEDGE:
	  elem = new Prism6();
	  break;
        case VTK_QUADRATIC_WEDGE:
	  elem = new Prism15();
	  break;
        case VTK_BIQUADRATIC_QUADRATIC_WEDGE:
	  elem = new Prism18();
	  break;
	case VTK_HEXAHEDRON:
	  elem = new Hex8();
	  break;
	case VTK_QUADRATIC_HEXAHEDRON:
  	  elem = new Hex20();
	  break;
        case VTK_TRIQUADRATIC_HEXAHEDRON:
	  elem = new Hex27();
	  break;
	case VTK_PYRAMID:
	  elem = new Pyramid5();
	  break;
	default:
	  libMesh::err << "element type not implemented in vtkinterface " << cell->GetCellType() << std::endl;
	  libmesh_error();
          break;
	}

      // get the straightforward numbering from the VTK cells
      for (unsigned int j=0; j<elem->n_nodes(); ++j)
        elem->set_node(j) = mesh.node_ptr(cell->GetPointId(j));

      // then get the connectivity
      std::vector<dof_id_type> conn;
      elem->connectivity(0, VTK, conn);

      // then reshuffle the nodes according to the connectivity, this
      // two-time-assign would evade the definition of the vtk_mapping
      for (unsigned int j=0; j<conn.size(); ++j)
        elem->set_node(j) = mesh.node_ptr(conn[j]);

      elem->set_id(i);

      elems_of_dimension[elem->dim()] = true;

      mesh.add_elem(elem);
    } // end loop over VTK cells

  // Set the mesh dimension to the largest encountered for an element
  for (unsigned int i=0; i!=4; ++i)
    if (elems_of_dimension[i])
      mesh.set_mesh_dimension(i);

#if LIBMESH_DIM < 3
  if (mesh.mesh_dimension() > LIBMESH_DIM)
    {
      libMesh::err << "Cannot open dimension " <<
		      mesh.mesh_dimension() <<
		      " mesh file when configured without " <<
                      mesh.mesh_dimension() << "D support." <<
                      std::endl;
      libmesh_error();
    }
#endif

#endif // LIBMESH_HAVE_VTK
}
示例#2
0
void
CombinedCreepPlasticity::computeStress( const Elem & current_elem,
                                        unsigned qp, const SymmElasticityTensor & elasticityTensor,
                                        const SymmTensor & stress_old, SymmTensor & strain_increment,
                                        SymmTensor & stress_new )
{
    // Given the stretching, compute the stress increment and add it to the old stress. Also update the creep strain
    // stress = stressOld + stressIncrement
    // creep_strain = creep_strainOld + creep_strainIncrement

    if(_t_step == 0) return;

    if (_output_iteration_info == true)
    {
        Moose::out
                << std::endl
                << "iteration output for CombinedCreepPlasticity solve:"
                << " time=" <<_t
                << " temperature=" << _temperature[qp]
                << " int_pt=" << qp
                << std::endl;
    }

    // compute trial stress
    stress_new = elasticityTensor * strain_increment;
    stress_new += stress_old;

    const SubdomainID current_block = current_elem.subdomain_id();
    const std::vector<ReturnMappingModel*> & rmm( _submodels[current_block] );
    const unsigned num_submodels = rmm.size();

    SymmTensor inelastic_strain_increment;

    SymmTensor elastic_strain_increment;
    SymmTensor stress_new_last( stress_new );
    Real delS(_absolute_tolerance+1);
    Real first_delS(delS);
    unsigned int counter(0);

    while(counter < _max_its &&
            delS > _absolute_tolerance &&
            (delS/first_delS) > _relative_tolerance &&
            (num_submodels != 1 || counter < 1))
    {
        elastic_strain_increment = strain_increment;
        stress_new = elasticityTensor * (elastic_strain_increment - inelastic_strain_increment);
        stress_new += stress_old;

        for (unsigned i_rmm(0); i_rmm < num_submodels; ++i_rmm)
        {
            rmm[i_rmm]->computeStress( current_elem, qp, elasticityTensor, stress_old, elastic_strain_increment,
                                       stress_new, inelastic_strain_increment );
        }

        // now check convergence
        SymmTensor deltaS(stress_new_last - stress_new);
        delS = std::sqrt(deltaS.doubleContraction(deltaS));
        if (counter == 0)
        {
            first_delS = delS;
        }
        stress_new_last = stress_new;

        if (_output_iteration_info == true)
        {
            Moose::out
                    << "stress_it=" << counter
                    << " rel_delS=" << (0 == first_delS ? 0 : delS/first_delS)
                    << " rel_tol="  << _relative_tolerance
                    << " abs_delS=" << delS
                    << " abs_tol="  << _absolute_tolerance
                    << std::endl;
        }

        ++counter;
    }

    if(counter == _max_its &&
            delS > _absolute_tolerance &&
            (delS/first_delS) > _relative_tolerance)
    {
        mooseError("Max stress iteration hit during CombinedCreepPlasticity solve!");
    }

    strain_increment = elastic_strain_increment;

}
bool MeshRefinement::eliminate_unrefined_patches ()
{
  // This function must be run on all processors at once
  parallel_only();

  bool flags_changed = false;

  MeshBase::element_iterator       elem_it  = _mesh.active_elements_begin();
  const MeshBase::element_iterator elem_end = _mesh.active_elements_end();

  for (; elem_it != elem_end; ++elem_it)
    {
      Elem* elem = *elem_it;
      // First assume that we'll have to flag this element for both h
      // and p refinement, then change our minds if we see any
      // neighbors that are as coarse or coarser than us.
      bool h_flag_me = true,
           p_flag_me = true;


      // Skip the element if it is already fully flagged for refinement
      if (elem->p_refinement_flag() == Elem::REFINE)
	p_flag_me = false;
      if (elem->refinement_flag() == Elem::REFINE)
        {
          h_flag_me = false;
          if (!p_flag_me)
            continue;
        }
      // Test the parent if that is already flagged for coarsening
      else if (elem->refinement_flag() == Elem::COARSEN)
        {
          libmesh_assert(elem->parent());
	  elem = elem->parent();
          // FIXME - this doesn't seem right - RHS
          if (elem->refinement_flag() != Elem::COARSEN_INACTIVE)
            continue;
          p_flag_me = false;
        }

      const unsigned int my_level = elem->level();
      int my_p_adjustment = 0;
      if (elem->p_refinement_flag() == Elem::REFINE)
        my_p_adjustment = 1;
      else if (elem->p_refinement_flag() == Elem::COARSEN)
        {
          libmesh_assert_greater (elem->p_level(), 0);
          my_p_adjustment = -1;
        }
      const unsigned int my_new_p_level = elem->p_level() +
                                          my_p_adjustment;

      // Check all the element neighbors
      for (unsigned int n=0; n<elem->n_neighbors(); n++)
        {
          const Elem *neighbor = elem->neighbor(n);
	  // Quit if the element is on a local boundary
	  if (neighbor == NULL || neighbor == remote_elem)
            {
              h_flag_me = false;
              p_flag_me = false;
              break;
            }
          // if the neighbor will be equally or less refined than
	  // we are, then we will not become an unrefined island.
          // So if we are still considering h refinement:
          if (h_flag_me &&
            // If our neighbor is already at a lower level,
            // it can't end up at a higher level even if it
            // is flagged for refinement once
             ((neighbor->level() < my_level) ||
            // If our neighbor is at the same level but isn't
            // flagged for refinement, it won't end up at a
            // higher level
             ((neighbor->active()) &&
              (neighbor->refinement_flag() != Elem::REFINE)) ||
            // If our neighbor is currently more refined but is
            // a parent flagged for coarsening, it will end up
            // at the same level.
             (neighbor->refinement_flag() == Elem::COARSEN_INACTIVE)))
            {
              // We've proven we won't become an unrefined island,
              // so don't h refine to avoid that.
	      h_flag_me = false;

              // If we've also proven we don't need to p refine,
              // we don't need to check more neighbors
              if (!p_flag_me)
                break;
            }
	  if (p_flag_me)
            {
	      // if active neighbors will have a p level
	      // equal to or lower than ours, then we do not need to p
              // refine ourselves.
              if (neighbor->active())
                {
                  int p_adjustment = 0;
                  if (neighbor->p_refinement_flag() == Elem::REFINE)
                    p_adjustment = 1;
                  else if (neighbor->p_refinement_flag() == Elem::COARSEN)
                    {
                      libmesh_assert_greater (neighbor->p_level(), 0);
                      p_adjustment = -1;
                    }
                  if (my_new_p_level >= neighbor->p_level() + p_adjustment)
                    {
                      p_flag_me = false;
                      if (!h_flag_me)
                        break;
                    }
                }
              // If we have inactive neighbors, we need to
              // test all their active descendants which neighbor us
              else if (neighbor->ancestor())
                {
                  if (neighbor->min_new_p_level_by_neighbor(elem,
                      my_new_p_level + 2) <= my_new_p_level)
                    {
                      p_flag_me = false;
                      if (!h_flag_me)
                        break;
                    }
                }
            }
        }

      if (h_flag_me)
	{
	  // Parents that would create islands should no longer
          // coarsen
          if (elem->refinement_flag() == Elem::COARSEN_INACTIVE)
            {
              for (unsigned int c=0; c<elem->n_children(); c++)
                {
                  libmesh_assert_equal_to (elem->child(c)->refinement_flag(),
                                          Elem::COARSEN);
                  elem->child(c)->set_refinement_flag(Elem::DO_NOTHING);
                }
              elem->set_refinement_flag(Elem::INACTIVE);
            }
          else
	    elem->set_refinement_flag(Elem::REFINE);
	  flags_changed = true;
	}
      if (p_flag_me)
	{
          if (elem->p_refinement_flag() == Elem::COARSEN)
	    elem->set_p_refinement_flag(Elem::DO_NOTHING);
          else
	    elem->set_p_refinement_flag(Elem::REFINE);
	  flags_changed = true;
	}
    }

  // If flags changed on any processor then they changed globally
  CommWorld.max(flags_changed);

  return flags_changed;
}
示例#4
0
void MeshBase::detect_interior_parents()
{
  // This requires an inspection on every processor
  parallel_object_only();

  // Check if the mesh contains mixed dimensions. If so, then set interior parents, otherwise return.
  if (this->elem_dimensions().size() == 1)
    return;

  //This map will be used to set interior parents
  LIBMESH_BEST_UNORDERED_MAP<dof_id_type, std::vector<dof_id_type> > node_to_elem;

  const_element_iterator el  = this->active_elements_begin();
  const_element_iterator end = this->active_elements_end();

  for (; el!=end; ++el)
    {
      const Elem * elem = *el;

      // Populating the node_to_elem map, same as MeshTools::build_nodes_to_elem_map
      for (unsigned int n=0; n<elem->n_vertices(); n++)
        {
          libmesh_assert_less (elem->id(), this->max_elem_id());

          node_to_elem[elem->node(n)].push_back(elem->id());
        }
    }

  // Automatically set interior parents
  el = this->elements_begin();
  for (; el!=end; ++el)
    {
      Elem * element = *el;

      // Ignore an 3D element or an element that already has an interior parent
      if (element->dim()>=LIBMESH_DIM || element->interior_parent())
        continue;

      // Start by generating a SET of elements that are dim+1 to the current
      // element at each vertex of the current element, thus ignoring interior nodes.
      // If one of the SET of elements is empty, then we will not have an interior parent
      // since an interior parent must be connected to all vertices of the current element
      std::vector< std::set<dof_id_type> > neighbors( element->n_vertices() );

      bool found_interior_parents = false;

      for (dof_id_type n=0; n < element->n_vertices(); n++)
        {
          std::vector<dof_id_type> & element_ids = node_to_elem[element->node(n)];
          for (std::vector<dof_id_type>::iterator e_it = element_ids.begin();
               e_it != element_ids.end(); e_it++)
            {
              dof_id_type eid = *e_it;
              if (this->elem(eid)->dim() == element->dim()+1)
                neighbors[n].insert(eid);
            }
          if (neighbors[n].size()>0)
            {
              found_interior_parents = true;
            }
          else
            {
              // We have found an empty set, no reason to continue
              // Ensure we set this flag to false before the break since it could have
              // been set to true for previous vertex
              found_interior_parents = false;
              break;
            }
        }

      // If we have successfully generated a set of elements for each vertex, we will compare
      // the set for vertex 0 will the sets for the vertices until we find a id that exists in
      // all sets.  If found, this is our an interior parent id.  The interior parent id found
      // will be the lowest element id if there is potential for multiple interior parents.
      if (found_interior_parents)
        {
          std::set<dof_id_type> & neighbors_0 = neighbors[0];
          for (std::set<dof_id_type>::iterator e_it = neighbors_0.begin();
               e_it != neighbors_0.end(); e_it++)
            {
              found_interior_parents=false;
              dof_id_type interior_parent_id = *e_it;
              for (dof_id_type n=1; n < element->n_vertices(); n++)
                {
                  if (neighbors[n].find(interior_parent_id)!=neighbors[n].end())
                    {
                      found_interior_parents=true;
                    }
                  else
                    {
                      found_interior_parents=false;
                      break;
                    }
                }
              if (found_interior_parents)
                {
                  element->set_interior_parent(this->elem(interior_parent_id));
                  break;
                }
            }
        }
    }
}
示例#5
0
void Elem::coarsen()
{
  libmesh_assert_equal_to (this->refinement_flag(), Elem::COARSEN_INACTIVE);
  libmesh_assert (!this->active());

  // We no longer delete children until MeshRefinement::contract()
  // delete [] _children;
  // _children = NULL;

  unsigned int parent_p_level = 0;

  // re-compute hanging node nodal locations
  for (unsigned int c=0; c<this->n_children(); c++)
  {
    Elem *mychild = this->child(c);
    if (mychild == remote_elem)
      continue;
    for (unsigned int nc=0; nc<mychild->n_nodes(); nc++)
    {
      Point new_pos;
      bool calculated_new_pos = false;

      for (unsigned int n=0; n<this->n_nodes(); n++)
      {
        // The value from the embedding matrix
        const float em_val = this->embedding_matrix(c,nc,n);

        // The node location is somewhere between existing vertices
        if ((em_val != 0.) && (em_val != 1.))
        {
	  new_pos.add_scaled (this->point(n), em_val);
	  calculated_new_pos = true;
        }
      }

      if(calculated_new_pos)
      {
	//Move the existing node back into it's original location
	for(unsigned int i=0; i<LIBMESH_DIM; i++)
	{
	  Point & child_node = *(mychild->get_node(nc));
	  child_node(i)=new_pos(i);
	}
      }
    }
  }

  for (unsigned int c=0; c<this->n_children(); c++)
    {
      Elem *mychild = this->child(c);
      if (mychild == remote_elem)
        continue;
      libmesh_assert_equal_to (mychild->refinement_flag(), Elem::COARSEN);
      mychild->set_refinement_flag(Elem::INACTIVE);
      if (mychild->p_level() > parent_p_level)
        parent_p_level = mychild->p_level();
    }

  this->set_refinement_flag(Elem::JUST_COARSENED);
  this->set_p_level(parent_p_level);

  libmesh_assert (this->active());
}
示例#6
0
// ------------------------------------------------------------
// MetisPartitioner implementation
void MetisPartitioner::_do_partition (MeshBase& mesh,
				      const unsigned int n_pieces)
{
  libmesh_assert_greater (n_pieces, 0);
  libmesh_assert (mesh.is_serial());

  // Check for an easy return
  if (n_pieces == 1)
    {
      this->single_partition (mesh);
      return;
    }

// What to do if the Metis library IS NOT present
#ifndef LIBMESH_HAVE_METIS

  libmesh_here();
  libMesh::err << "ERROR: The library has been built without"    << std::endl
	        << "Metis support.  Using a space-filling curve"  << std::endl
	        << "partitioner instead!"                         << std::endl;

  SFCPartitioner sfcp;

  sfcp.partition (mesh, n_pieces);

// What to do if the Metis library IS present
#else

  START_LOG("partition()", "MetisPartitioner");

  const dof_id_type n_active_elem = mesh.n_active_elem();

  // build the graph
  // std::vector<int> options(5);
  std::vector<int> vwgt(n_active_elem);
  std::vector<int> part(n_active_elem);

  int
    n = static_cast<int>(n_active_elem),  // number of "nodes" (elements)
                                          //   in the graph
//    wgtflag = 2,                          // weights on vertices only,
//                                          //   none on edges
//    numflag = 0,                          // C-style 0-based numbering
    nparts  = static_cast<int>(n_pieces), // number of subdomains to create
    edgecut = 0;                          // the numbers of edges cut by the
                                          //   resulting partition

  // Set the options
  // options[0] = 0; // use default options

  // Metis will only consider the active elements.
  // We need to map the active element ids into a
  // contiguous range.  Further, we want the unique range indexing to be
  // independednt of the element ordering, otherwise a circular dependency
  // can result in which the partitioning depends on the ordering which
  // depends on the partitioning...
  std::map<const Elem*, dof_id_type> global_index_map;
  {
    std::vector<dof_id_type> global_index;

    MeshBase::element_iterator       it  = mesh.active_elements_begin();
    const MeshBase::element_iterator end = mesh.active_elements_end();

    MeshCommunication().find_global_indices (MeshTools::bounding_box(mesh),
					     it, end, global_index);

    libmesh_assert_equal_to (global_index.size(), n_active_elem);

    for (std::size_t cnt=0; it != end; ++it)
      {
	const Elem *elem = *it;
	libmesh_assert (!global_index_map.count(elem));

	global_index_map[elem]  = global_index[cnt++];
      }
    libmesh_assert_equal_to (global_index_map.size(), n_active_elem);
  }


  // build the graph in CSR format.  Note that
  // the edges in the graph will correspond to
  // face neighbors
  std::vector<int> xadj, adjncy;
  {
    std::vector<const Elem*> neighbors_offspring;

    MeshBase::element_iterator       elem_it  = mesh.active_elements_begin();
    const MeshBase::element_iterator elem_end = mesh.active_elements_end();

    // This will be exact when there is no refinement and all the
    // elements are of the same type.
    std::size_t graph_size=0;
    std::vector<std::vector<dof_id_type> > graph(n_active_elem);

    for (; elem_it != elem_end; ++elem_it)
      {
	const Elem* elem = *elem_it;

	libmesh_assert (global_index_map.count(elem));

	const dof_id_type elem_global_index =
	  global_index_map[elem];

	libmesh_assert_less (elem_global_index, vwgt.size());
	libmesh_assert_less (elem_global_index, graph.size());

	// maybe there is a better weight?
	// The weight is used to define what a balanced graph is
        if(!_weights)
          vwgt[elem_global_index] = elem->n_nodes();
        else
          vwgt[elem_global_index] = static_cast<int>((*_weights)[elem->id()]);

	// Loop over the element's neighbors.  An element
	// adjacency corresponds to a face neighbor
	for (unsigned int ms=0; ms<elem->n_neighbors(); ms++)
	  {
	    const Elem* neighbor = elem->neighbor(ms);

	    if (neighbor != NULL)
	      {
		// If the neighbor is active treat it
		// as a connection
		if (neighbor->active())
		  {
		    libmesh_assert (global_index_map.count(neighbor));

		    const dof_id_type neighbor_global_index =
		      global_index_map[neighbor];

		    graph[elem_global_index].push_back(neighbor_global_index);
		    graph_size++;
		  }

#ifdef LIBMESH_ENABLE_AMR

		// Otherwise we need to find all of the
		// neighbor's children that are connected to
		// us and add them
		else
		  {
		    // The side of the neighbor to which
		    // we are connected
		    const unsigned int ns =
		      neighbor->which_neighbor_am_i (elem);
                    libmesh_assert_less (ns, neighbor->n_neighbors());

		    // Get all the active children (& grandchildren, etc...)
		    // of the neighbor.
		    neighbor->active_family_tree (neighbors_offspring);

		    // Get all the neighbor's children that
		    // live on that side and are thus connected
		    // to us
		    for (unsigned int nc=0; nc<neighbors_offspring.size(); nc++)
		      {
			const Elem* child =
			  neighbors_offspring[nc];

			// This does not assume a level-1 mesh.
			// Note that since children have sides numbered
			// coincident with the parent then this is a sufficient test.
			if (child->neighbor(ns) == elem)
			  {
			    libmesh_assert (child->active());
			    libmesh_assert (global_index_map.count(child));

			    const dof_id_type child_global_index =
			      global_index_map[child];

			    graph[elem_global_index].push_back(child_global_index);
			    graph_size++;
			  }
		      }
		  }

#endif /* ifdef LIBMESH_ENABLE_AMR */

	      }
	  }
      }

    // Convert the graph into the format Metis wants
    xadj.reserve(n_active_elem+1);
    adjncy.reserve(graph_size);

    for (std::size_t r=0; r<graph.size(); r++)
      {
	xadj.push_back(adjncy.size());
	std::vector<dof_id_type> graph_row; // build this emtpy
	graph_row.swap(graph[r]); // this will deallocate at the end of scope
	adjncy.insert(adjncy.end(),
		      graph_row.begin(),
		      graph_row.end());
      }

    // The end of the adjacency array for the last elem
    xadj.push_back(adjncy.size());

    libmesh_assert_equal_to (adjncy.size(), graph_size);
    libmesh_assert_equal_to (xadj.size(), n_active_elem+1);
  } // done building the graph


  if (adjncy.empty())
    adjncy.push_back(0);

  int ncon = 1;

  // Select which type of partitioning to create

  // Use recursive if the number of partitions is less than or equal to 8
  if (n_pieces <= 8)
    Metis::METIS_PartGraphRecursive(&n, &ncon, &xadj[0], &adjncy[0], &vwgt[0], NULL,
				    NULL, &nparts, NULL, NULL, NULL,
				    &edgecut, &part[0]);

  // Otherwise  use kway
  else
    Metis::METIS_PartGraphKway(&n, &ncon, &xadj[0], &adjncy[0], &vwgt[0], NULL,
			       NULL, &nparts, NULL, NULL, NULL,
			       &edgecut, &part[0]);


  // Assign the returned processor ids.  The part array contains
  // the processor id for each active element, but in terms of
  // the contiguous indexing we defined above
  {
    MeshBase::element_iterator       it  = mesh.active_elements_begin();
    const MeshBase::element_iterator end = mesh.active_elements_end();

    for (; it!=end; ++it)
      {
	Elem* elem = *it;

	libmesh_assert (global_index_map.count(elem));

	const dof_id_type elem_global_index =
	  global_index_map[elem];

	libmesh_assert_less (elem_global_index, part.size());
	const processor_id_type elem_procid =
	  static_cast<processor_id_type>(part[elem_global_index]);

        elem->processor_id() = elem_procid;
      }
  }

  STOP_LOG("partition()", "MetisPartitioner");
#endif
}
void
MultiAppUserObjectTransfer::execute()
{
  _console << "Beginning MultiAppUserObjectTransfer " << name() << std::endl;

  switch (_direction)
  {
    case TO_MULTIAPP:
    {
      for (unsigned int i=0; i<_multi_app->numGlobalApps(); i++)
      {
        if (_multi_app->hasLocalApp(i))
        {
          MPI_Comm swapped = Moose::swapLibMeshComm(_multi_app->comm());

          // Loop over the master nodes and set the value of the variable
          System * to_sys = find_sys(_multi_app->appProblem(i)->es(), _to_var_name);

          unsigned int sys_num = to_sys->number();
          unsigned int var_num = to_sys->variable_number(_to_var_name);

          NumericVector<Real> & solution = _multi_app->appTransferVector(i, _to_var_name);

          MeshBase * mesh = NULL;

          if (_displaced_target_mesh && _multi_app->appProblem(i)->getDisplacedProblem())
          {
            mesh = &_multi_app->appProblem(i)->getDisplacedProblem()->mesh().getMesh();
          }
          else
            mesh = &_multi_app->appProblem(i)->mesh().getMesh();

          bool is_nodal = to_sys->variable_type(var_num).family == LAGRANGE;

          const UserObject & user_object = _multi_app->problem()->getUserObjectBase(_user_object_name);

          if (is_nodal)
          {
            MeshBase::const_node_iterator node_it = mesh->local_nodes_begin();
            MeshBase::const_node_iterator node_end = mesh->local_nodes_end();

            for (; node_it != node_end; ++node_it)
            {
              Node * node = *node_it;

              if (node->n_dofs(sys_num, var_num) > 0) // If this variable has dofs at this node
              {
                // The zero only works for LAGRANGE!
                dof_id_type dof = node->dof_number(sys_num, var_num, 0);

                // Swap back
                Moose::swapLibMeshComm(swapped);
                Real from_value = user_object.spatialValue(*node+_multi_app->position(i));
                // Swap again
                swapped = Moose::swapLibMeshComm(_multi_app->comm());

                solution.set(dof, from_value);
              }
            }
          }
          else // Elemental
          {
            MeshBase::const_element_iterator elem_it = mesh->local_elements_begin();
            MeshBase::const_element_iterator elem_end = mesh->local_elements_end();

            for (; elem_it != elem_end; ++elem_it)
            {
              Elem * elem = *elem_it;

              Point centroid = elem->centroid();

              if (elem->n_dofs(sys_num, var_num) > 0) // If this variable has dofs at this elem
              {
                // The zero only works for LAGRANGE!
                dof_id_type dof = elem->dof_number(sys_num, var_num, 0);

                // Swap back
                Moose::swapLibMeshComm(swapped);
                Real from_value = user_object.spatialValue(centroid+_multi_app->position(i));
                // Swap again
                swapped = Moose::swapLibMeshComm(_multi_app->comm());

                solution.set(dof, from_value);
              }
            }
          }

          solution.close();
          to_sys->update();

          // Swap back
          Moose::swapLibMeshComm(swapped);
        }
      }

      break;
    }
    case FROM_MULTIAPP:
    {
      FEProblem & to_problem = *_multi_app->problem();
      MooseVariable & to_var = to_problem.getVariable(0, _to_var_name);
      SystemBase & to_system_base = to_var.sys();

      System & to_sys = to_system_base.system();

      unsigned int to_sys_num = to_sys.number();

      // Only works with a serialized mesh to transfer to!
      mooseAssert(to_sys.get_mesh().is_serial(), "MultiAppUserObjectTransfer only works with SerialMesh!");

      unsigned int to_var_num = to_sys.variable_number(to_var.name());

      _console << "Transferring to: " << to_var.name() << std::endl;

      // EquationSystems & to_es = to_sys.get_equation_systems();

      //Create a serialized version of the solution vector
      NumericVector<Number> * to_solution = to_sys.solution.get();

      MeshBase * to_mesh = NULL;

      if (_displaced_target_mesh && to_problem.getDisplacedProblem())
        to_mesh = &to_problem.getDisplacedProblem()->mesh().getMesh();
      else
        to_mesh = &to_problem.mesh().getMesh();

      bool is_nodal = to_sys.variable_type(to_var_num).family == LAGRANGE;

      for (unsigned int i=0; i<_multi_app->numGlobalApps(); i++)
      {
        if (!_multi_app->hasLocalApp(i))
          continue;

        Point app_position = _multi_app->position(i);
        MeshTools::BoundingBox app_box = _multi_app->getBoundingBox(i);
        const UserObject & user_object = _multi_app->appUserObjectBase(i, _user_object_name);

        if (is_nodal)
        {
          MeshBase::const_node_iterator node_it = to_mesh->nodes_begin();
          MeshBase::const_node_iterator node_end = to_mesh->nodes_end();

          for (; node_it != node_end; ++node_it)
          {
            Node * node = *node_it;

            if (node->n_dofs(to_sys_num, to_var_num) > 0) // If this variable has dofs at this node
            {
              // See if this node falls in this bounding box
              if (app_box.contains_point(*node))
              {
                dof_id_type dof = node->dof_number(to_sys_num, to_var_num, 0);

                MPI_Comm swapped = Moose::swapLibMeshComm(_multi_app->comm());
                Real from_value = user_object.spatialValue(*node-app_position);
                Moose::swapLibMeshComm(swapped);

                to_solution->set(dof, from_value);
              }
            }
          }
        }
        else // Elemental
        {
          MeshBase::const_element_iterator elem_it = to_mesh->elements_begin();
          MeshBase::const_element_iterator elem_end = to_mesh->elements_end();

          for (; elem_it != elem_end; ++elem_it)
          {
            Elem * elem = *elem_it;

            if (elem->n_dofs(to_sys_num, to_var_num) > 0) // If this variable has dofs at this elem
            {
              Point centroid = elem->centroid();

              // See if this elem falls in this bounding box
              if (app_box.contains_point(centroid))
              {
                dof_id_type dof = elem->dof_number(to_sys_num, to_var_num, 0);

                MPI_Comm swapped = Moose::swapLibMeshComm(_multi_app->comm());
                Real from_value = user_object.spatialValue(centroid-app_position);
                Moose::swapLibMeshComm(swapped);

                to_solution->set(dof, from_value);
              }
            }
          }
        }
      }

      to_solution->close();
      to_sys.update();

      break;
    }
  }

  _console << "Finished MultiAppUserObjectTransfer " << name() << std::endl;
}
void MeshRefinement::flag_elements_by_elem_fraction (const ErrorVector& error_per_cell,
						     const Real refine_frac,
						     const Real coarsen_frac,
						     const unsigned int max_l)
{
  parallel_object_only();

  // The function arguments are currently just there for
  // backwards_compatibility
  if (!_use_member_parameters)
  {
    // If the user used non-default parameters, lets warn
    // that they're deprecated
    if (refine_frac != 0.3 ||
	coarsen_frac != 0.0 ||
	max_l != libMesh::invalid_uint)
      libmesh_deprecated();

    _refine_fraction = refine_frac;
    _coarsen_fraction = coarsen_frac;
    _max_h_level = max_l;
  }

  // Check for valid fractions..
  // The fraction values must be in [0,1]
  libmesh_assert_greater_equal (_refine_fraction, 0);
  libmesh_assert_less_equal (_refine_fraction, 1);
  libmesh_assert_greater_equal (_coarsen_fraction, 0);
  libmesh_assert_less_equal (_coarsen_fraction, 1);

  // The number of active elements in the mesh
  const dof_id_type n_active_elem  = _mesh.n_elem();

  // The number of elements to flag for coarsening
  const dof_id_type n_elem_coarsen =
    static_cast<dof_id_type>(_coarsen_fraction * n_active_elem);

  // The number of elements to flag for refinement
  const dof_id_type n_elem_refine =
    static_cast<dof_id_type>(_refine_fraction  * n_active_elem);



  // Clean up the refinement flags.  These could be left
  // over from previous refinement steps.
  this->clean_refinement_flags();


  // This vector stores the error and element number for all the
  // active elements.  It will be sorted and the top & bottom
  // elements will then be flagged for coarsening & refinement
  std::vector<ErrorVectorReal> sorted_error;

  sorted_error.reserve (n_active_elem);

  // Loop over the active elements and create the entry
  // in the sorted_error vector
  MeshBase::element_iterator       elem_it  = _mesh.active_local_elements_begin();
  const MeshBase::element_iterator elem_end = _mesh.active_local_elements_end();

  for (; elem_it != elem_end; ++elem_it)
    sorted_error.push_back (error_per_cell[(*elem_it)->id()]);

  this->comm().allgather(sorted_error);

  // Now sort the sorted_error vector
  std::sort (sorted_error.begin(), sorted_error.end());

  // If we're coarsening by parents:
  // Create a sorted error vector with coarsenable parent elements
  // only, sorted by lowest errors first
  ErrorVector error_per_parent, sorted_parent_error;
  if (_coarsen_by_parents)
  {
    Real parent_error_min, parent_error_max;

    create_parent_error_vector(error_per_cell,
			       error_per_parent,
			       parent_error_min,
			       parent_error_max);

    sorted_parent_error = error_per_parent;
    std::sort (sorted_parent_error.begin(), sorted_parent_error.end());

    // All the other error values will be 0., so get rid of them.
    sorted_parent_error.erase (std::remove(sorted_parent_error.begin(),
					   sorted_parent_error.end(), 0.),
			       sorted_parent_error.end());
  }


  ErrorVectorReal top_error= 0., bottom_error = 0.;

  // Get the maximum error value corresponding to the
  // bottom n_elem_coarsen elements
  if (_coarsen_by_parents && n_elem_coarsen)
    {
      const unsigned int dim = _mesh.mesh_dimension();
      unsigned int twotodim = 1;
      for (unsigned int i=0; i!=dim; ++i)
        twotodim *= 2;

      dof_id_type n_parent_coarsen = n_elem_coarsen / (twotodim - 1);

      if (n_parent_coarsen)
	bottom_error = sorted_parent_error[n_parent_coarsen - 1];
    }
  else if (n_elem_coarsen)
    {
      bottom_error = sorted_error[n_elem_coarsen - 1];
    }

  if (n_elem_refine)
    top_error = sorted_error[sorted_error.size() - n_elem_refine];

  // Finally, let's do the element flagging
  elem_it  = _mesh.active_elements_begin();
  for (; elem_it != elem_end; ++elem_it)
    {
      Elem* elem = *elem_it;
      Elem* parent = elem->parent();

      if (_coarsen_by_parents && parent && n_elem_coarsen &&
          error_per_parent[parent->id()] <= bottom_error)
        elem->set_refinement_flag(Elem::COARSEN);

      if (!_coarsen_by_parents && n_elem_coarsen &&
          error_per_cell[elem->id()] <= bottom_error)
        elem->set_refinement_flag(Elem::COARSEN);

      if (n_elem_refine &&
          elem->level() < _max_h_level &&
          error_per_cell[elem->id()] >= top_error)
        elem->set_refinement_flag(Elem::REFINE);
    }
}
void MeshRefinement::flag_elements_by_mean_stddev (const ErrorVector& error_per_cell,
						   const Real refine_frac,
						   const Real coarsen_frac,
						   const unsigned int max_l)
{
  // The function arguments are currently just there for
  // backwards_compatibility
  if (!_use_member_parameters)
    {
      // If the user used non-default parameters, lets warn
      // that they're deprecated
      if (refine_frac != 0.3 ||
          coarsen_frac != 0.0 ||
          max_l != libMesh::invalid_uint)
        libmesh_deprecated();

      _refine_fraction = refine_frac;
      _coarsen_fraction = coarsen_frac;
      _max_h_level = max_l;
    }

  // Get the mean value from the error vector
  const Real mean = error_per_cell.mean();

  // Get the standard deviation.  This equals the
  // square-root of the variance
  const Real stddev = std::sqrt (error_per_cell.variance());

  // Check for valid fractions
  libmesh_assert_greater_equal (_refine_fraction, 0);
  libmesh_assert_less_equal (_refine_fraction, 1);
  libmesh_assert_greater_equal (_coarsen_fraction, 0);
  libmesh_assert_less_equal (_coarsen_fraction, 1);

  // The refine and coarsen cutoff
  const Real refine_cutoff  =  mean + _refine_fraction  * stddev;
  const Real coarsen_cutoff =  std::max(mean - _coarsen_fraction * stddev, 0.);

  // Loop over the elements and flag them for coarsening or
  // refinement based on the element error
  MeshBase::element_iterator       elem_it  = _mesh.active_elements_begin();
  const MeshBase::element_iterator elem_end = _mesh.active_elements_end();

  for (; elem_it != elem_end; ++elem_it)
    {
      Elem* elem             = *elem_it;
      const dof_id_type id  = elem->id();

      libmesh_assert_less (id, error_per_cell.size());

      const ErrorVectorReal elem_error = error_per_cell[id];

      // Possibly flag the element for coarsening ...
      if (elem_error <= coarsen_cutoff)
	elem->set_refinement_flag(Elem::COARSEN);

      // ... or refinement
      if ((elem_error >= refine_cutoff) && (elem->level() < _max_h_level))
	elem->set_refinement_flag(Elem::REFINE);
    }
}
示例#10
0
bool MeshRefinement::flag_elements_by_nelem_target (const ErrorVector& error_per_cell)
{
  parallel_object_only();

  // Check for valid fractions..
  // The fraction values must be in [0,1]
  libmesh_assert_greater_equal (_refine_fraction, 0);
  libmesh_assert_less_equal (_refine_fraction, 1);
  libmesh_assert_greater_equal (_coarsen_fraction, 0);
  libmesh_assert_less_equal (_coarsen_fraction, 1);

  // This function is currently only coded to work when coarsening by
  // parents - it's too hard to guess how many coarsenings will be
  // performed otherwise.
  libmesh_assert (_coarsen_by_parents);

  // The number of active elements in the mesh - hopefully less than
  // 2 billion on 32 bit machines
  const dof_id_type n_active_elem  = _mesh.n_active_elem();

  // The maximum number of active elements to flag for coarsening
  const dof_id_type max_elem_coarsen =
    static_cast<dof_id_type>(_coarsen_fraction * n_active_elem) + 1;

  // The maximum number of elements to flag for refinement
  const dof_id_type max_elem_refine  =
    static_cast<dof_id_type>(_refine_fraction  * n_active_elem) + 1;

  // Clean up the refinement flags.  These could be left
  // over from previous refinement steps.
  this->clean_refinement_flags();

  // The target number of elements to add or remove
  const std::ptrdiff_t n_elem_new = _nelem_target - n_active_elem;

  // Create an vector with active element errors and ids,
  // sorted by highest errors first
  const dof_id_type max_elem_id = _mesh.max_elem_id();
  std::vector<std::pair<ErrorVectorReal, dof_id_type> > sorted_error;

  sorted_error.reserve (n_active_elem);

  // On a ParallelMesh, we need to communicate to know which remote ids
  // correspond to active elements.
  {
    std::vector<bool> is_active(max_elem_id, false);

    MeshBase::element_iterator       elem_it  = _mesh.active_local_elements_begin();
    const MeshBase::element_iterator elem_end = _mesh.active_local_elements_end();
    for (; elem_it != elem_end; ++elem_it)
      {
        const dof_id_type eid = (*elem_it)->id();
        is_active[eid] = true;
        libmesh_assert_less (eid, error_per_cell.size());
        sorted_error.push_back
          (std::make_pair(error_per_cell[eid], eid));
      }

    this->comm().max(is_active);

    this->comm().allgather(sorted_error);
  }

  // Default sort works since pairs are sorted lexicographically
  std::sort (sorted_error.begin(), sorted_error.end());
  std::reverse (sorted_error.begin(), sorted_error.end());

  // Create a sorted error vector with coarsenable parent elements
  // only, sorted by lowest errors first
  ErrorVector error_per_parent;
  std::vector<std::pair<ErrorVectorReal, dof_id_type> > sorted_parent_error;
  Real parent_error_min, parent_error_max;

  create_parent_error_vector(error_per_cell,
                             error_per_parent,
                             parent_error_min,
                             parent_error_max);

  // create_parent_error_vector sets values for non-parents and
  // non-coarsenable parents to -1.  Get rid of them.
  for (dof_id_type i=0; i != error_per_parent.size(); ++i)
    if (error_per_parent[i] != -1)
      sorted_parent_error.push_back(std::make_pair(error_per_parent[i], i));

  std::sort (sorted_parent_error.begin(), sorted_parent_error.end());

  // Keep track of how many elements we plan to coarsen & refine
  dof_id_type coarsen_count = 0;
  dof_id_type refine_count = 0;

  const unsigned int dim = _mesh.mesh_dimension();
  unsigned int twotodim = 1;
  for (unsigned int i=0; i!=dim; ++i)
    twotodim *= 2;

  // First, let's try to get our element count to target_nelem
  if (n_elem_new >= 0)
  {
    // Every element refinement creates at least
    // 2^dim-1 new elements
    refine_count =
      std::min(libmesh_cast_int<dof_id_type>(n_elem_new / (twotodim-1)),
	       max_elem_refine);
  }
  else
  {
    // Every successful element coarsening is likely to destroy
    // 2^dim-1 net elements.
    coarsen_count =
      std::min(libmesh_cast_int<dof_id_type>(-n_elem_new / (twotodim-1)),
	       max_elem_coarsen);
  }

  // Next, let's see if we can trade any refinement for coarsening
  while (coarsen_count < max_elem_coarsen &&
         refine_count < max_elem_refine &&
         coarsen_count < sorted_parent_error.size() &&
         refine_count < sorted_error.size() &&
         sorted_error[refine_count].first >
	 sorted_parent_error[coarsen_count].first * _coarsen_threshold)
  {
    coarsen_count++;
    refine_count++;
  }

  // On a ParallelMesh, we need to communicate to know which remote ids
  // correspond to refinable elements
  dof_id_type successful_refine_count = 0;
  {
    std::vector<bool> is_refinable(max_elem_id, false);

    for (dof_id_type i=0; i != sorted_error.size(); ++i)
      {
        dof_id_type eid = sorted_error[i].second;
        Elem *elem = _mesh.query_elem(eid);
        if (elem && elem->level() < _max_h_level)
	  is_refinable[eid] = true;
      }
    this->comm().max(is_refinable);

    if (refine_count > max_elem_refine)
      refine_count = max_elem_refine;
    for (dof_id_type i=0; i != sorted_error.size(); ++i)
      {
        if (successful_refine_count >= refine_count)
          break;

        dof_id_type eid = sorted_error[i].second;
        Elem *elem = _mesh.query_elem(eid);
        if (is_refinable[eid])
          {
            if (elem)
	      elem->set_refinement_flag(Elem::REFINE);
	    successful_refine_count++;
          }
      }
  }

  // If we couldn't refine enough elements, don't coarsen too many
  // either
  if (coarsen_count < (refine_count - successful_refine_count))
    coarsen_count = 0;
  else
    coarsen_count -= (refine_count - successful_refine_count);

  if (coarsen_count > max_elem_coarsen)
    coarsen_count = max_elem_coarsen;

  dof_id_type successful_coarsen_count = 0;
  if (coarsen_count)
    {
      for (dof_id_type i=0; i != sorted_parent_error.size(); ++i)
        {
          if (successful_coarsen_count >= coarsen_count * twotodim)
            break;

          dof_id_type parent_id = sorted_parent_error[i].second;
          Elem *parent = _mesh.query_elem(parent_id);

          // On a ParallelMesh we skip remote elements
          if (!parent)
            continue;

          libmesh_assert(parent->has_children());
          for (unsigned int c=0; c != parent->n_children(); ++c)
            {
              Elem *elem = parent->child(c);
              if (elem && elem != remote_elem)
                {
                  libmesh_assert(elem->active());
                  elem->set_refinement_flag(Elem::COARSEN);
                  successful_coarsen_count++;
                }
            }
        }
    }

  // Return true if we've done all the AMR/C we can
  if (!successful_coarsen_count &&
      !successful_refine_count)
    return true;
  // And false if there may still be more to do.
  return false;
}
示例#11
0
//-----------------------------------------------------------------
// Mesh refinement methods
void MeshRefinement::flag_elements_by_error_fraction (const ErrorVector& error_per_cell,
						      const Real refine_frac,
						      const Real coarsen_frac,
						      const unsigned int max_l)
{
  parallel_object_only();

  // The function arguments are currently just there for
  // backwards_compatibility
  if (!_use_member_parameters)
  {
    // If the user used non-default parameters, lets warn
    // that they're deprecated
    if (refine_frac != 0.3 ||
	coarsen_frac != 0.0 ||
	max_l != libMesh::invalid_uint)
      libmesh_deprecated();

    _refine_fraction = refine_frac;
    _coarsen_fraction = coarsen_frac;
    _max_h_level = max_l;
  }

  // Check for valid fractions..
  // The fraction values must be in [0,1]
  libmesh_assert_greater_equal (_refine_fraction, 0);
  libmesh_assert_less_equal (_refine_fraction, 1);
  libmesh_assert_greater_equal (_coarsen_fraction, 0);
  libmesh_assert_less_equal (_coarsen_fraction, 1);

  // Clean up the refinement flags.  These could be left
  // over from previous refinement steps.
  this->clean_refinement_flags();

  // We're getting the minimum and maximum error values
  // for the ACTIVE elements
  Real error_min = 1.e30;
  Real error_max = 0.;

  // And, if necessary, for their parents
  Real parent_error_min = 1.e30;
  Real parent_error_max = 0.;

  // Prepare another error vector if we need to sum parent errors
  ErrorVector error_per_parent;
  if (_coarsen_by_parents)
  {
    create_parent_error_vector(error_per_cell,
			       error_per_parent,
			       parent_error_min,
			       parent_error_max);
  }

  // We need to loop over all active elements to find the minimum
  MeshBase::element_iterator       el_it  =
    _mesh.active_local_elements_begin();
  const MeshBase::element_iterator el_end =
    _mesh.active_local_elements_end();

  for (; el_it != el_end; ++el_it)
  {
    const dof_id_type id  = (*el_it)->id();
    libmesh_assert_less (id, error_per_cell.size());

    error_max = std::max (error_max, error_per_cell[id]);
    error_min = std::min (error_min, error_per_cell[id]);
  }
  this->comm().max(error_max);
  this->comm().min(error_min);

  // Compute the cutoff values for coarsening and refinement
  const Real error_delta = (error_max - error_min);
  const Real parent_error_delta = parent_error_max - parent_error_min;

  const Real refine_cutoff  = (1.- _refine_fraction)*error_max;
  const Real coarsen_cutoff = _coarsen_fraction*error_delta + error_min;
  const Real parent_cutoff = _coarsen_fraction*parent_error_delta + error_min;

//   // Print information about the error
//   libMesh::out << " Error Information:"                     << std::endl
// 	    << " ------------------"                     << std::endl
// 	    << "   min:              " << error_min      << std::endl
// 	    << "   max:              " << error_max      << std::endl
// 	    << "   delta:            " << error_delta    << std::endl
// 	    << "     refine_cutoff:  " << refine_cutoff  << std::endl
// 	    << "     coarsen_cutoff: " << coarsen_cutoff << std::endl;



  // Loop over the elements and flag them for coarsening or
  // refinement based on the element error

  MeshBase::element_iterator       e_it  =
    _mesh.active_elements_begin();
  const MeshBase::element_iterator e_end =
    _mesh.active_elements_end();
  for (; e_it != e_end; ++e_it)
  {
    Elem* elem           = *e_it;
    const dof_id_type id = elem->id();

    libmesh_assert_less (id, error_per_cell.size());

    const ErrorVectorReal elem_error = error_per_cell[id];

    if (_coarsen_by_parents)
    {
      Elem* parent           = elem->parent();
      if (parent)
      {
	const dof_id_type parentid  = parent->id();
	if (error_per_parent[parentid] >= 0. &&
	    error_per_parent[parentid] <= parent_cutoff)
	  elem->set_refinement_flag(Elem::COARSEN);
      }
    }
    // Flag the element for coarsening if its error
    // is <= coarsen_fraction*delta + error_min
    else if (elem_error <= coarsen_cutoff)
    {
      elem->set_refinement_flag(Elem::COARSEN);
    }

    // Flag the element for refinement if its error
    // is >= refinement_cutoff.
    if (elem_error >= refine_cutoff)
      if (elem->level() < _max_h_level)
	elem->set_refinement_flag(Elem::REFINE);
  }
}
示例#12
0
void MeshRefinement::flag_elements_by_error_tolerance (const ErrorVector& error_per_cell_in)
{
  parallel_object_only();

  libmesh_assert_greater (_coarsen_threshold, 0);

  // Check for valid fractions..
  // The fraction values must be in [0,1]
  libmesh_assert_greater_equal (_refine_fraction, 0);
  libmesh_assert_less_equal (_refine_fraction, 1);
  libmesh_assert_greater_equal (_coarsen_fraction, 0);
  libmesh_assert_less_equal (_coarsen_fraction, 1);

  // How much error per cell will we tolerate?
  const Real local_refinement_tolerance =
    _absolute_global_tolerance / std::sqrt(static_cast<Real>(_mesh.n_active_elem()));
  const Real local_coarsening_tolerance =
    local_refinement_tolerance * _coarsen_threshold;

  // Prepare another error vector if we need to sum parent errors
  ErrorVector error_per_parent;
  if (_coarsen_by_parents)
  {
    Real parent_error_min, parent_error_max;

    create_parent_error_vector(error_per_cell_in,
			       error_per_parent,
			       parent_error_min,
			       parent_error_max);
  }

  MeshBase::element_iterator       elem_it  = _mesh.active_elements_begin();
  const MeshBase::element_iterator elem_end = _mesh.active_elements_end();

  for (; elem_it != elem_end; ++elem_it)
  {
    Elem* elem = *elem_it;
    Elem* parent = elem->parent();
    const dof_id_type elem_number    = elem->id();
    const ErrorVectorReal elem_error = error_per_cell_in[elem_number];

    if (elem_error > local_refinement_tolerance &&
	elem->level() < _max_h_level)
      elem->set_refinement_flag(Elem::REFINE);

    if (!_coarsen_by_parents && elem_error <
	local_coarsening_tolerance)
      elem->set_refinement_flag(Elem::COARSEN);

    if (_coarsen_by_parents && parent)
    {
      ErrorVectorReal parent_error = error_per_parent[parent->id()];
      if (parent_error >= 0.)
      {
	const Real parent_coarsening_tolerance =
	  std::sqrt(parent->n_children() *
		    local_coarsening_tolerance *
		    local_coarsening_tolerance);
	if (parent_error < parent_coarsening_tolerance)
	  elem->set_refinement_flag(Elem::COARSEN);
      }
    }
  }
}
示例#13
0
void ExodusII_IO::read (const std::string & fname)
{
  // Get a reference to the mesh we are reading
  MeshBase & mesh = MeshInput<MeshBase>::mesh();

  // Clear any existing mesh data
  mesh.clear();

  // Keep track of what kinds of elements this file contains
  elems_of_dimension.clear();
  elems_of_dimension.resize(4, false);

#ifdef DEBUG
  this->verbose(true);
#endif

  // Instantiate the ElementMaps interface
  ExodusII_IO_Helper::ElementMaps em(*exio_helper);

  // Open the exodus file in EX_READ mode
  exio_helper->open(fname.c_str(), /*read_only=*/true);

  // Get header information from exodus file
  exio_helper->read_header();

  // Read the QA records
  exio_helper->read_qa_records();

  // Print header information
  exio_helper->print_header();

  // Read nodes from the exodus file
  exio_helper->read_nodes();

  // Reserve space for the nodes.
  mesh.reserve_nodes(exio_helper->num_nodes);

  // Read the node number map from the Exodus file.  This is
  // required if we want to preserve the numbering of nodes as it
  // exists in the Exodus file.  If the Exodus file does not contain
  // a node_num_map, the identity map is returned by this call.
  exio_helper->read_node_num_map();

  // Loop over the nodes, create Nodes with local processor_id 0.
  for (int i=0; i<exio_helper->num_nodes; i++)
    {
      // Use the node_num_map to get the correct ID for Exodus
      int exodus_id = exio_helper->node_num_map[i];

      // Catch the node that was added to the mesh
      Node * added_node = mesh.add_point (Point(exio_helper->x[i], exio_helper->y[i], exio_helper->z[i]), exodus_id-1);

      // If the Mesh assigned an ID different from what is in the
      // Exodus file, we should probably error.
      if (added_node->id() != static_cast<unsigned>(exodus_id-1))
        libmesh_error_msg("Error!  Mesh assigned node ID "    \
                          << added_node->id()                         \
                          << " which is different from the (zero-based) Exodus ID " \
                          << exodus_id-1                              \
                          << "!");
    }

  // This assert is no longer valid if the nodes are not numbered
  // sequentially starting from 1 in the Exodus file.
  // libmesh_assert_equal_to (static_cast<unsigned int>(exio_helper->num_nodes), mesh.n_nodes());

  // Get information about all the blocks
  exio_helper->read_block_info();

  // Reserve space for the elements
  mesh.reserve_elem(exio_helper->num_elem);

  // Read the element number map from the Exodus file.  This is
  // required if we want to preserve the numbering of elements as it
  // exists in the Exodus file.  If the Exodus file does not contain
  // an elem_num_map, the identity map is returned by this call.
  exio_helper->read_elem_num_map();

  // Read in the element connectivity for each block.
  int nelem_last_block = 0;

  // Loop over all the blocks
  for (int i=0; i<exio_helper->num_elem_blk; i++)
    {
      // Read the information for block i
      exio_helper->read_elem_in_block (i);
      int subdomain_id = exio_helper->get_block_id(i);

      // populate the map of names
      std::string subdomain_name = exio_helper->get_block_name(i);
      if (!subdomain_name.empty())
        mesh.subdomain_name(static_cast<subdomain_id_type>(subdomain_id)) = subdomain_name;

      // Set any relevant node/edge maps for this element
      const std::string type_str (exio_helper->get_elem_type());
      const ExodusII_IO_Helper::Conversion conv = em.assign_conversion(type_str);

      // Loop over all the faces in this block
      int jmax = nelem_last_block+exio_helper->num_elem_this_blk;
      for (int j=nelem_last_block; j<jmax; j++)
        {
          Elem * elem = Elem::build (conv.get_canonical_type()).release();
          libmesh_assert (elem);
          elem->subdomain_id() = static_cast<subdomain_id_type>(subdomain_id) ;

          // Use the elem_num_map to obtain the ID of this element in the Exodus file
          int exodus_id = exio_helper->elem_num_map[j];

          // Assign this element the same ID it had in the Exodus
          // file, but make it zero-based by subtracting 1.  Note:
          // some day we could use 1-based numbering in libmesh and
          // thus match the Exodus numbering exactly, but at the
          // moment libmesh is zero-based.
          elem->set_id(exodus_id-1);

          // Record that we have seen an element of dimension elem->dim()
          elems_of_dimension[elem->dim()] = true;

          // Catch the Elem pointer that the Mesh throws back
          elem = mesh.add_elem (elem);

          // If the Mesh assigned an ID different from what is in the
          // Exodus file, we should probably error.
          if (elem->id() != static_cast<unsigned>(exodus_id-1))
            libmesh_error_msg("Error!  Mesh assigned ID "       \
                              << elem->id()                             \
                              << " which is different from the (zero-based) Exodus ID " \
                              << exodus_id-1                            \
                              << "!");

          // Set all the nodes for this element
          for (int k=0; k<exio_helper->num_nodes_per_elem; k++)
            {
              // global index
              int gi = (j-nelem_last_block)*exio_helper->num_nodes_per_elem + conv.get_node_map(k);

              // The entries in 'connect' are actually (1-based)
              // indices into the node_num_map, so to get the right
              // node ID we:
              // 1.) Subtract 1 from connect[gi]
              // 2.) Pass it through node_num_map to get the corresponding Exodus ID
              // 3.) Subtract 1 from that, since libmesh node numbering is "zero"-based,
              //     even when the Exodus node numbering doesn't start with 1.
              int libmesh_node_id = exio_helper->node_num_map[exio_helper->connect[gi] - 1] - 1;

              // Set the node pointer in the Elem
              elem->set_node(k) = mesh.node_ptr(libmesh_node_id);
            }
        }

      // running sum of # of elements per block,
      // (should equal total number of elements in the end)
      nelem_last_block += exio_helper->num_elem_this_blk;
    }

  // This assert isn't valid if the Exodus file's numbering doesn't
  // start with 1!  For example, if Exodus's elem_num_map is 21, 22,
  // 23, 24, 25, 26, 27, 28, 29, 30, ... 84, then by the time you are
  // done with the loop above, mesh.n_elem() will report 84 and
  // nelem_last_block will be 64.
  // libmesh_assert_equal_to (static_cast<unsigned>(nelem_last_block), mesh.n_elem());

  // Set the mesh dimension to the largest encountered for an element
  for (unsigned char i=0; i!=4; ++i)
    if (elems_of_dimension[i])
      mesh.set_mesh_dimension(i);

  // Read in sideset information -- this is useful for applying boundary conditions
  {
    // Get basic information about all sidesets
    exio_helper->read_sideset_info();
    int offset=0;
    for (int i=0; i<exio_helper->num_side_sets; i++)
      {
        // Compute new offset
        offset += (i > 0 ? exio_helper->num_sides_per_set[i-1] : 0);
        exio_helper->read_sideset (i, offset);

        std::string sideset_name = exio_helper->get_side_set_name(i);
        if (!sideset_name.empty())
          mesh.get_boundary_info().sideset_name
            (cast_int<boundary_id_type>(exio_helper->get_side_set_id(i)))
            = sideset_name;
      }

    for (unsigned int e=0; e<exio_helper->elem_list.size(); e++)
      {
        // The numbers in the Exodus file sidesets should be thought
        // of as (1-based) indices into the elem_num_map array.  So,
        // to get the right element ID we have to:
        // 1.) Subtract 1 from elem_list[e] (to get a zero-based index)
        // 2.) Pass it through elem_num_map (to get the corresponding Exodus ID)
        // 3.) Subtract 1 from that, since libmesh is "zero"-based,
        //     even when the Exodus numbering doesn't start with 1.
        dof_id_type libmesh_elem_id =
          cast_int<dof_id_type>(exio_helper->elem_num_map[exio_helper->elem_list[e] - 1] - 1);

        // Set any relevant node/edge maps for this element
        Elem * elem = mesh.elem(libmesh_elem_id);

        const ExodusII_IO_Helper::Conversion conv = em.assign_conversion(elem->type());

        // Map the zero-based Exodus side numbering to the libmesh side numbering
        int mapped_side = conv.get_side_map(exio_helper->side_list[e]-1);

        // Check for errors
        if (mapped_side == ExodusII_IO_Helper::Conversion::invalid_id)
          libmesh_error_msg("Invalid 1-based side id: "                 \
                            << exio_helper->side_list[e]                \
                            << " detected for "                         \
                            << Utility::enum_to_string(elem->type()));

        // Add this (elem,side,id) triplet to the BoundaryInfo object.
        mesh.get_boundary_info().add_side (libmesh_elem_id,
                                           cast_int<unsigned short>(mapped_side),
                                           cast_int<boundary_id_type>(exio_helper->id_list[e]));
      }
  }

  // Read nodeset info
  {
    exio_helper->read_nodeset_info();

    for (int nodeset=0; nodeset<exio_helper->num_node_sets; nodeset++)
      {
        boundary_id_type nodeset_id =
          cast_int<boundary_id_type>(exio_helper->nodeset_ids[nodeset]);

        std::string nodeset_name = exio_helper->get_node_set_name(nodeset);
        if (!nodeset_name.empty())
          mesh.get_boundary_info().nodeset_name(nodeset_id) = nodeset_name;

        exio_helper->read_nodeset(nodeset);

        for (unsigned int node=0; node<exio_helper->node_list.size(); node++)
          {
            // As before, the entries in 'node_list' are 1-based
            // indcies into the node_num_map array, so we have to map
            // them.  See comment above.
            int libmesh_node_id = exio_helper->node_num_map[exio_helper->node_list[node] - 1] - 1;
            mesh.get_boundary_info().add_node(cast_int<dof_id_type>(libmesh_node_id),
                                              nodeset_id);
          }
      }
  }

#if LIBMESH_DIM < 3
  if (mesh.mesh_dimension() > LIBMESH_DIM)
    libmesh_error_msg("Cannot open dimension "        \
                      << mesh.mesh_dimension()            \
                      << " mesh file when configured without "        \
                      << mesh.mesh_dimension()                        \
                      << "D support.");
#endif
}
示例#14
0
// ------------------------------------------------------------
// SFCPartitioner implementation
void SFCPartitioner::_do_partition (MeshBase& mesh,
				    const unsigned int n)
{

  libmesh_assert_greater (n, 0);

  // Check for an easy return
  if (n == 1)
    {
      this->single_partition (mesh);
      return;
    }

// What to do if the sfcurves library IS NOT present
#ifndef LIBMESH_HAVE_SFCURVES

  libmesh_here();
  libMesh::err << "ERROR: The library has been built without"    << std::endl
	        << "Space Filling Curve support.  Using a linear" << std::endl
	        << "partitioner instead!" << std::endl;

  LinearPartitioner lp;

  lp.partition (mesh, n);

// What to do if the sfcurves library IS present
#else

  START_LOG("sfc_partition()", "SFCPartitioner");

  const unsigned int n_active_elem = mesh.n_active_elem();
  const unsigned int n_elem        = mesh.n_elem();

  // the forward_map maps the active element id
  // into a contiguous block of indices
  std::vector<unsigned int>
    forward_map (n_elem, libMesh::invalid_uint);

  // the reverse_map maps the contiguous ids back
  // to active elements
  std::vector<Elem*> reverse_map (n_active_elem, NULL);

  int size = static_cast<int>(n_active_elem);
  std::vector<double> x      (size);
  std::vector<double> y      (size);
  std::vector<double> z      (size);
  std::vector<int>    table  (size);


  // We need to map the active element ids into a
  // contiguous range.
  {
//     active_elem_iterator       elem_it (mesh.elements_begin());
//     const active_elem_iterator elem_end(mesh.elements_end());

    MeshBase::element_iterator       elem_it  = mesh.active_elements_begin();
    const MeshBase::element_iterator elem_end = mesh.active_elements_end();

    unsigned int el_num = 0;

    for (; elem_it != elem_end; ++elem_it)
      {
	libmesh_assert_less ((*elem_it)->id(), forward_map.size());
	libmesh_assert_less (el_num, reverse_map.size());

	forward_map[(*elem_it)->id()] = el_num;
	reverse_map[el_num]           = *elem_it;
	el_num++;
      }
    libmesh_assert_equal_to (el_num, n_active_elem);
  }


  // Get the centroid for each active element
  {
//     const_active_elem_iterator       elem_it (mesh.const_elements_begin());
//     const const_active_elem_iterator elem_end(mesh.const_elements_end());

    MeshBase::element_iterator       elem_it  = mesh.active_elements_begin();
    const MeshBase::element_iterator elem_end = mesh.active_elements_end();

    for (; elem_it != elem_end; ++elem_it)
      {
	const Elem* elem = *elem_it;

	libmesh_assert_less (elem->id(), forward_map.size());

	const Point p = elem->centroid();

	x[forward_map[elem->id()]] = p(0);
	y[forward_map[elem->id()]] = p(1);
	z[forward_map[elem->id()]] = p(2);
      }
  }

  // build the space-filling curve
  if (_sfc_type == "Hilbert")
    Sfc::hilbert (&x[0], &y[0], &z[0], &size, &table[0]);

  else if (_sfc_type == "Morton")
    Sfc::morton  (&x[0], &y[0], &z[0], &size, &table[0]);

  else
    {
      libmesh_here();
      libMesh::err << "ERROR: Unknown type: " << _sfc_type << std::endl
		    << " Valid types are"                   << std::endl
		    << "  \"Hilbert\""                      << std::endl
		    << "  \"Morton\""                       << std::endl
		    << " "                                  << std::endl
		    << "Proceeding with a Hilbert curve."   << std::endl;

      Sfc::hilbert (&x[0], &y[0], &z[0], &size, &table[0]);
    }


  // Assign the partitioning to the active elements
  {
//      {
//        std::ofstream out ("sfc.dat");
//        out << "variables=x,y,z" << std::endl;
//        out << "zone f=point" << std::endl;

//        for (unsigned int i=0; i<n_active_elem; i++)
//  	out << x[i] << " "
//  	    << y[i] << " "
//  	    << z[i] << std::endl;
//      }

    const unsigned int blksize = (n_active_elem+n-1)/n;

    for (unsigned int i=0; i<n_active_elem; i++)
      {
	libmesh_assert_less (static_cast<unsigned int>(table[i]-1), reverse_map.size());

	Elem* elem = reverse_map[table[i]-1];

	elem->processor_id() = i/blksize;
      }
  }

  STOP_LOG("sfc_partition()", "SFCPartitioner");

#endif

}
示例#15
0
void ParmetisPartitioner::assign_partitioning (MeshBase& mesh)
{
  // This function must be run on all processors at once
  libmesh_parallel_only(mesh.comm());

  const dof_id_type
    first_local_elem = _vtxdist[mesh.processor_id()];

  std::vector<std::vector<dof_id_type> >
    requested_ids(mesh.n_processors()),
    requests_to_fill(mesh.n_processors());

  MeshBase::element_iterator elem_it  = mesh.active_elements_begin();
  MeshBase::element_iterator elem_end = mesh.active_elements_end();

  for (; elem_it != elem_end; ++elem_it)
    {
      Elem *elem = *elem_it;

      // we need to get the index from the owning processor
      // (note we cannot assign it now -- we are iterating
      // over elements again and this will be bad!)
      libmesh_assert_less (elem->processor_id(), requested_ids.size());
      requested_ids[elem->processor_id()].push_back(elem->id());
    }

  // Trade with all processors (including self) to get their indices
  for (processor_id_type pid=0; pid<mesh.n_processors(); pid++)
    {
      // Trade my requests with processor procup and procdown
      const processor_id_type procup = (mesh.processor_id() + pid) %
        mesh.n_processors();
      const processor_id_type procdown = (mesh.n_processors() +
                                          mesh.processor_id() - pid) %
        mesh.n_processors();

      mesh.comm().send_receive (procup,   requested_ids[procup],
                                procdown, requests_to_fill[procdown]);

      // we can overwrite these requested ids in-place.
      for (std::size_t i=0; i<requests_to_fill[procdown].size(); i++)
        {
          const dof_id_type requested_elem_index =
            requests_to_fill[procdown][i];

          libmesh_assert(_global_index_by_pid_map.count(requested_elem_index));

          const dof_id_type global_index_by_pid =
            _global_index_by_pid_map[requested_elem_index];

          const dof_id_type local_index =
            global_index_by_pid - first_local_elem;

          libmesh_assert_less (local_index, _part.size());
          libmesh_assert_less (local_index, mesh.n_active_local_elem());

          const unsigned int elem_procid =
            static_cast<unsigned int>(_part[local_index]);

          libmesh_assert_less (elem_procid, static_cast<unsigned int>(_nparts));

          requests_to_fill[procdown][i] = elem_procid;
        }

      // Trade back
      mesh.comm().send_receive (procdown, requests_to_fill[procdown],
                                procup,   requested_ids[procup]);
    }

  // and finally assign the partitioning.
  // note we are iterating in exactly the same order
  // used to build up the request, so we can expect the
  // required entries to be in the proper sequence.
  elem_it  = mesh.active_elements_begin();
  elem_end = mesh.active_elements_end();

  for (std::vector<unsigned int> counters(mesh.n_processors(), 0);
       elem_it != elem_end; ++elem_it)
    {
      Elem *elem = *elem_it;

      const processor_id_type current_pid = elem->processor_id();

      libmesh_assert_less (counters[current_pid], requested_ids[current_pid].size());

      const processor_id_type elem_procid =
        requested_ids[current_pid][counters[current_pid]++];

      libmesh_assert_less (elem_procid, static_cast<unsigned int>(_nparts));
      elem->processor_id() = elem_procid;
    }
}
示例#16
0
// Begin the main program.
int main (int argc, char ** argv)
{
  // Initialize libMesh and any dependent libaries, like in example 2.
  LibMeshInit init (argc, argv);

  // Declare a performance log for the main program
  // PerfLog perf_main("Main Program");

  // Create a GetPot object to parse the command line
  GetPot command_line (argc, argv);

  // Check for proper calling arguments.
  if (argc < 3)
    {
      // This handy function will print the file name, line number,
      // specified message, and then throw an exception.
      libmesh_error_msg("Usage:\n" << "\t " << argv[0] << " -d 2(3)" << " -n 15");
    }

  // Brief message to the user regarding the program name
  // and command line arguments.
  else
    {
      libMesh::out << "Running " << argv[0];

      for (int i=1; i<argc; i++)
        libMesh::out << " " << argv[i];

      libMesh::out << std::endl << std::endl;
    }


  // Read problem dimension from command line.  Use int
  // instead of unsigned since the GetPot overload is ambiguous
  // otherwise.
  int dim = 2;
  if (command_line.search(1, "-d"))
    dim = command_line.next(dim);

  // Skip higher-dimensional examples on a lower-dimensional libMesh build
  libmesh_example_requires(dim <= LIBMESH_DIM, "2D/3D support");

  // Create a mesh with user-defined dimension on the default MPI
  // communicator.
  Mesh mesh (init.comm(), dim);

  // Read number of elements from command line
  int ps = 15;
  if (command_line.search(1, "-n"))
    ps = command_line.next(ps);

  // Read FE order from command line
  std::string order = "SECOND";
  if (command_line.search(2, "-Order", "-o"))
    order = command_line.next(order);

  // Read FE Family from command line
  std::string family = "LAGRANGE";
  if (command_line.search(2, "-FEFamily", "-f"))
    family = command_line.next(family);

  // Cannot use discontinuous basis.
  if ((family == "MONOMIAL") || (family == "XYZ"))
    {
      if (mesh.processor_id() == 0)
        libmesh_error_msg("This example requires a C^0 (or higher) FE basis.");
    }

  // Use the MeshTools::Generation mesh generator to create a uniform
  // grid on the square [-1,1]^D.  We instruct the mesh generator
  // to build a mesh of 8x8 Quad9 elements in 2D, or Hex27
  // elements in 3D.  Building these higher-order elements allows
  // us to use higher-order approximation, as in example 3.

  Real halfwidth = dim > 1 ? 1. : 0.;
  Real halfheight = dim > 2 ? 1. : 0.;

  if ((family == "LAGRANGE") && (order == "FIRST"))
    {
      // No reason to use high-order geometric elements if we are
      // solving with low-order finite elements.
      MeshTools::Generation::build_cube (mesh,
                                         ps,
                                         (dim>1) ? ps : 0,
                                         (dim>2) ? ps : 0,
                                         -1., 1.,
                                         -halfwidth, halfwidth,
                                         -halfheight, halfheight,
                                         (dim==1)    ? EDGE2 :
                                         ((dim == 2) ? QUAD4 : HEX8));
    }

  else
    {
      MeshTools::Generation::build_cube (mesh,
                                         ps,
                                         (dim>1) ? ps : 0,
                                         (dim>2) ? ps : 0,
                                         -1., 1.,
                                         -halfwidth, halfwidth,
                                         -halfheight, halfheight,
                                         (dim==1)    ? EDGE3 :
                                         ((dim == 2) ? QUAD9 : HEX27));
    }

  {
    MeshBase::element_iterator       el     = mesh.elements_begin();
    const MeshBase::element_iterator end_el = mesh.elements_end();

    for ( ; el != end_el; ++el)
      {
        Elem * elem = *el;
        const Point cent = elem->centroid();
        if (dim > 1)
          {
            if ((cent(0) > 0) == (cent(1) > 0))
              elem->subdomain_id() = 1;
          }
        else
          {
            if (cent(0) > 0)
              elem->subdomain_id() = 1;
          }
      }
  }

  // Print information about the mesh to the screen.
  mesh.print_info();

  // Create an equation systems object.
  EquationSystems equation_systems (mesh);

  // Declare the system and its variables.
  // Create a system named "Poisson"
  LinearImplicitSystem & system =
    equation_systems.add_system<LinearImplicitSystem> ("Poisson");


  std::set<subdomain_id_type> active_subdomains;


  // Add the variable "u" to "Poisson".  "u"
  // will be approximated using second-order approximation.
  active_subdomains.clear(); active_subdomains.insert(0);
  system.add_variable("u",
                      Utility::string_to_enum<Order>   (order),
                      Utility::string_to_enum<FEFamily>(family),
                      &active_subdomains);

  // Add the variable "v" to "Poisson".  "v"
  // will be approximated using second-order approximation.
  active_subdomains.clear(); active_subdomains.insert(1);
  system.add_variable("v",
                      Utility::string_to_enum<Order>   (order),
                      Utility::string_to_enum<FEFamily>(family),
                      &active_subdomains);

  // Give the system a pointer to the matrix assembly
  // function.
  system.attach_assemble_function (assemble_poisson);

  // Initialize the data structures for the equation system.
  equation_systems.init();

  // Print information about the system to the screen.
  equation_systems.print_info();
  mesh.print_info();

  // Solve the system "Poisson", just like example 2.
  equation_systems.get_system("Poisson").solve();

  // After solving the system write the solution
  // to a GMV-formatted plot file.
  if (dim == 1)
    {
      GnuPlotIO plot(mesh, "Subdomains Example 2, 1D", GnuPlotIO::GRID_ON);
      plot.write_equation_systems("gnuplot_script", equation_systems);
    }
  else
    {
#ifdef LIBMESH_HAVE_EXODUS_API
      ExodusII_IO (mesh).write_equation_systems ((dim == 3) ?
                                                 "out_3.e" : "out_2.e", equation_systems);
#endif // #ifdef LIBMESH_HAVE_EXODUS_API
    }

  // All done.
  return 0;
}
示例#17
0
void
FeatureFloodCount::FeatureData::updateBBoxExtremes(MeshTools::BoundingBox & bbox, const Elem & elem)
{
  for (auto node_n = decltype(elem.n_nodes())(0); node_n < elem.n_nodes();  ++node_n)
    updateBBoxExtremes(bbox, *(elem.get_node(node_n)));
}
示例#18
0
int main(int argc, char** argv)
{
    LibMeshInit init(argc, argv);

    GetPot cl(argc, argv);

    int dim = -1;
    if (!cl.search("--dim"))
    {
        std::cerr << "No --dim argument found!" << std::endl;
        usage_error(argv[0]);
    }
    dim = cl.next(dim);

    Mesh mesh(dim);

    if(!cl.search("--input"))
    {
        std::cerr << "No --input argument found!" << std::endl;
        usage_error(argv[0]);
    }
    const char* meshname = cl.next("mesh.xda");

    mesh.read(meshname);
    std::cout << "Loaded mesh " << meshname << std::endl;

    if(!cl.search("--newbcid"))
    {
        std::cerr << "No --bcid argument found!" << std::endl;
        usage_error(argv[0]);
    }
    boundary_id_type bcid = 0;
    bcid = cl.next(bcid);

    Point minnormal(-std::numeric_limits<Real>::max(),
                    -std::numeric_limits<Real>::max(),
                    -std::numeric_limits<Real>::max());
    Point maxnormal(std::numeric_limits<Real>::max(),
                    std::numeric_limits<Real>::max(),
                    std::numeric_limits<Real>::max());
    Point minpoint(-std::numeric_limits<Real>::max(),
                   -std::numeric_limits<Real>::max(),
                   -std::numeric_limits<Real>::max());
    Point maxpoint(std::numeric_limits<Real>::max(),
                   std::numeric_limits<Real>::max(),
                   std::numeric_limits<Real>::max());

    if (cl.search("--minnormalx"))
        minnormal(0) = cl.next(minnormal(0));
    if (cl.search("--minnormalx"))
        minnormal(0) = cl.next(minnormal(0));
    if (cl.search("--maxnormalx"))
        maxnormal(0) = cl.next(maxnormal(0));
    if (cl.search("--minnormaly"))
        minnormal(1) = cl.next(minnormal(1));
    if (cl.search("--maxnormaly"))
        maxnormal(1) = cl.next(maxnormal(1));
    if (cl.search("--minnormalz"))
        minnormal(2) = cl.next(minnormal(2));
    if (cl.search("--maxnormalz"))
        maxnormal(2) = cl.next(maxnormal(2));

    if (cl.search("--minpointx"))
        minpoint(0) = cl.next(minpoint(0));
    if (cl.search("--maxpointx"))
        maxpoint(0) = cl.next(maxpoint(0));
    if (cl.search("--minpointy"))
        minpoint(1) = cl.next(minpoint(1));
    if (cl.search("--maxpointy"))
        maxpoint(1) = cl.next(maxpoint(1));
    if (cl.search("--minpointz"))
        minpoint(2) = cl.next(minpoint(2));
    if (cl.search("--maxpointz"))
        maxpoint(2) = cl.next(maxpoint(2));

    std::cout << "min point = " << minpoint << std::endl;
    std::cout << "max point = " << maxpoint << std::endl;
    std::cout << "min normal = " << minnormal << std::endl;
    std::cout << "max normal = " << maxnormal << std::endl;

    bool matcholdbcid = false;
    boundary_id_type oldbcid = 0;
    if (cl.search("--oldbcid"))
    {
        matcholdbcid = true;
        oldbcid = cl.next(oldbcid);
        if (oldbcid < 0)
            oldbcid = BoundaryInfo::invalid_id;
    }

    AutoPtr<FEBase> fe = FEBase::build(dim, FEType(FIRST,LAGRANGE));
    QGauss qface(dim-1, CONSTANT);
    fe->attach_quadrature_rule(&qface);
    const std::vector<Point> &face_points = fe->get_xyz();
    const std::vector<Point> &face_normals = fe->get_normals();

    MeshBase::element_iterator           el = mesh.elements_begin();
    const MeshBase::element_iterator end_el = mesh.elements_end();
    for (; el != end_el; ++el)
    {
        Elem *elem = *el;
        unsigned int n_sides = elem->n_sides();
        for (unsigned int s=0; s != n_sides; ++s)
        {
            if (elem->neighbor(s))
                continue;

            fe->reinit(elem,s);
            const Point &p = face_points[0];
            const Point &n = face_normals[0];

//std::cout << "elem = " << elem->id() << std::endl;
//std::cout << "centroid = " << elem->centroid() << std::endl;
//std::cout << "p = " << p << std::endl;
//std::cout << "n = " << n << std::endl;

            if (p(0) > minpoint(0) && p(0) < maxpoint(0) &&
                    p(1) > minpoint(1) && p(1) < maxpoint(1) &&
                    p(2) > minpoint(2) && p(2) < maxpoint(2) &&
                    n(0) > minnormal(0) && n(0) < maxnormal(0) &&
                    n(1) > minnormal(1) && n(1) < maxnormal(1) &&
                    n(2) > minnormal(2) && n(2) < maxnormal(2))
            {
                if (matcholdbcid &&
                        mesh.boundary_info->boundary_id(elem, s) != oldbcid)
                    continue;
                mesh.boundary_info->remove_side(elem, s);
                mesh.boundary_info->add_side(elem, s, bcid);
//std::cout << "Set element " << elem->id() << " side " << s <<
//             " to boundary " << bcid << std::endl;
            }
        }
    }

    std::string outputname;
    if(cl.search("--output"))
    {
        outputname = cl.next("mesh.xda");
    }
    else
    {
        outputname = "new.";
        outputname += meshname;
    }


    mesh.write(outputname.c_str());
    std::cout << "Wrote mesh " << outputname << std::endl;

    return 0;
}
示例#19
0
void
MaterialPropertyStorage::prolongStatefulProps(
    const std::vector<std::vector<QpMap>> & refinement_map,
    QBase & qrule,
    QBase & qrule_face,
    MaterialPropertyStorage & parent_material_props,
    MaterialData & child_material_data,
    const Elem & elem,
    const int input_parent_side,
    const int input_child,
    const int input_child_side)
{
  mooseAssert(input_child != -1 || input_parent_side == input_child_side, "Invalid inputs!");

  unsigned int n_qpoints = 0;

  // If we passed in -1 for these then we really need to store properties at 0
  unsigned int parent_side = input_parent_side == -1 ? 0 : input_parent_side;
  unsigned int child_side = input_child_side == -1 ? 0 : input_child_side;

  if (input_child_side == -1) // Not doing side projection (ie, doing volume projection)
    n_qpoints = qrule.n_points();
  else
    n_qpoints = qrule_face.n_points();

  child_material_data.resize(n_qpoints);

  unsigned int n_children = elem.n_children();

  std::vector<unsigned int> children;

  if (input_child != -1) // Passed in a child explicitly
    children.push_back(input_child);
  else
  {
    children.resize(n_children);
    for (unsigned int child = 0; child < n_children; child++)
      children[child] = child;
  }

  for (const auto & child : children)
  {
    // If we're not projecting an internal child side, but we are projecting sides, see if this
    // child is on that side
    if (input_child == -1 && input_child_side != -1 && !elem.is_child_on_side(child, parent_side))
      continue;

    const Elem * child_elem = elem.child_ptr(child);

    mooseAssert(child < refinement_map.size(), "Refinement_map vector not initialized");
    const std::vector<QpMap> & child_map = refinement_map[child];

    initProps(child_material_data, *child_elem, child_side, n_qpoints);

    for (unsigned int i = 0; i < _stateful_prop_id_to_prop_id.size(); ++i)
    {
      // Copy from the parent stateful properties
      for (unsigned int qp = 0; qp < refinement_map[child].size(); qp++)
      {
        PropertyValue * child_property = props(child_elem, child_side)[i];
        mooseAssert(props().contains(&elem),
                    "Parent pointer is not in the MaterialProps data structure");
        PropertyValue * parent_property = parent_material_props.props(&elem, parent_side)[i];

        child_property->qpCopy(qp, parent_property, child_map[qp]._to);
        propsOld(child_elem, child_side)[i]->qpCopy(
            qp, parent_material_props.propsOld(&elem, parent_side)[i], child_map[qp]._to);
        if (hasOlderProperties())
          propsOlder(child_elem, child_side)[i]->qpCopy(
              qp, parent_material_props.propsOlder(&elem, parent_side)[i], child_map[qp]._to);
      }
    }
  }
}
示例#20
0
int main (int argc, char** argv)
{
  LibMeshInit init(argc, argv);

  PerfMon perfmon(argv[0]);

  unsigned int n_subdomains = 1;
  unsigned int n_rsteps = 0;
  unsigned char dim = static_cast<unsigned char>(-1); // invalid dimension
  double dist_fact = 0.;
  bool verbose = false;
  BoundaryMeshWriteMode write_bndry = BM_DISABLED;
  unsigned int convert_second_order = 0;
  bool addinfelems = false;
  bool triangulate = false;
  bool do_quality = false;
  ElemQuality quality_type = DIAGONAL;

#ifdef LIBMESH_ENABLE_INFINITE_ELEMENTS
  InfElemBuilder::InfElemOriginValue origin_x(false, 0.);
  InfElemBuilder::InfElemOriginValue origin_y(false, 0.);
  InfElemBuilder::InfElemOriginValue origin_z(false, 0.);
#endif

  bool x_sym=false;
  bool y_sym=false;
  bool z_sym=false;


  std::vector<std::string> names;
  std::vector<std::string> var_names;
  std::vector<Number>      soln;

  process_cmd_line(argc, argv, names,
                   n_subdomains, n_rsteps, dim,
                   dist_fact, verbose, write_bndry,
                   convert_second_order,

                   triangulate,

                   do_quality,
                   quality_type,

                   addinfelems,

#ifdef LIBMESH_ENABLE_INFINITE_ELEMENTS
                   origin_x, origin_y, origin_z,
#endif

                   x_sym, y_sym, z_sym);

  UniquePtr<Mesh> mesh_ptr;
  if (dim == static_cast<unsigned char>(-1))
    {
      mesh_ptr.reset(new Mesh(init.comm()));
    }
  else
    {
      mesh_ptr.reset(new Mesh(init.comm(),dim));
    }

  Mesh& mesh = *mesh_ptr;
  MeshData mesh_data(mesh);

  /**
   * Read the input mesh
   */
  if (!names.empty())
    {
      /*
       * activate the MeshData of the dim mesh,
       * so that it can be copied to the boundary
       */

      if (write_bndry == BM_WITH_MESHDATA)
        {
          mesh_data.activate();

          if (verbose)
            mesh_data.print_info();
        }


      mesh.read(names[0]);

      if (verbose)
        {
          mesh.print_info();
          mesh.get_boundary_info().print_summary();
        }

    }

  else
    {
      libMesh::out << "No input specified." << std::endl;
      return 1;
    }



#ifdef LIBMESH_ENABLE_INFINITE_ELEMENTS

  if(addinfelems)
    {
      if (names.size() == 3)
        {
          libMesh::out << "ERROR: Invalid combination: Building infinite elements " << std::endl
                       << "not compatible with solution import." << std::endl;
          exit(1);
        }

      if (write_bndry != BM_DISABLED)
        {
          libMesh::out << "ERROR: Invalid combination: Building infinite elements " << std::endl
                       << "not compatible with writing boundary conditions." << std::endl;
          exit(1);
        }

      /*
       * Sanity checks: -X/Y/Z can only be used, when the
       * corresponding coordinate is also given (using -x/y/z)
       */
      if ((x_sym && !origin_x.first) ||     // claim x-symmetry, but x-coordinate of origin not given!
          (y_sym && !origin_y.first) ||     // the same for y
          (z_sym && !origin_z.first))       // the same for z
        {
          libMesh::out << "ERROR: When x-symmetry is requested using -X, then" << std::endl
                       << "the option -x <coord> also has to be given." << std::endl
                       << "This holds obviously for y and z, too." << std::endl;
          exit(1);
        }


      // build infinite elements
      InfElemBuilder(mesh).build_inf_elem(origin_x, origin_y, origin_z,
                                          x_sym, y_sym, z_sym,
                                          verbose);


      if (verbose)
        {
          mesh.print_info();
          mesh.get_boundary_info().print_summary();
        }

    }

  // sanity check
  else if((origin_x.first ||  origin_y.first || origin_z.first) ||
          (x_sym          ||  y_sym          || z_sym))
    {
      libMesh::out << "ERROR:  -x/-y/-z/-X/-Y/-Z is only to be used when" << std::endl
                   << "the option -a is also specified!" << std::endl;
      exit(1);
    }

#endif


  /**
   * Possibly read the solution
   */
  if (names.size() == 3)
    LegacyXdrIO(mesh,true).read_mgf_soln(names[2],
                                         soln,
                                         var_names);



  /**
   * Maybe Triangulate
   */
  //  if (dim == 2 && triangulate)
  if (triangulate)
    {
      if (verbose)
        libMesh::out << "...Converting to all simplices...\n";

      MeshTools::Modification::all_tri(mesh);
    }

  /**
   * Compute Shape quality metrics
   */
  if (do_quality)
    {
      StatisticsVector<Real> sv;
      sv.reserve(mesh.n_elem());

      libMesh::out << "Quality type is: " << Quality::name(quality_type) << std::endl;

      // What are the quality bounds for this element?
      std::pair<Real, Real> bounds = mesh.elem(0)->qual_bounds(quality_type);
      libMesh::out << "Quality bounds for this element type are: (" << bounds.first
                   << ", " << bounds.second << ") "
                   << std::endl;

      MeshBase::const_element_iterator it  = mesh.active_elements_begin(),
        end = mesh.active_elements_end();
      for (; it != end; ++it)
        {
          Elem *e = *it;
          sv.push_back(e->quality(quality_type));
        }

      const unsigned int n_bins = 10;
      libMesh::out << "Avg. shape quality: " << sv.mean() << std::endl;

      // Find element indices below the specified cutoff.
      // These might be considered "bad" elements which need refinement.
      std::vector<dof_id_type> bad_elts  = sv.cut_below(0.8);
      libMesh::out << "Found " << bad_elts.size()
                   << " of " << mesh.n_elem()
                   << " elements below the cutoff." << std::endl;

      /*
        for (unsigned int i=0; i<bad_elts.size(); i++)
        libMesh::out << bad_elts[i] << " ";
        libMesh::out << std::endl;
      */

      // Compute the histogram for this distribution
      std::vector<dof_id_type> histogram;
      sv.histogram(histogram, n_bins);

      /*
        for (unsigned int i=0; i<n_bins; i++)
        histogram[i] = histogram[i] / mesh.n_elem();
      */

      const bool do_matlab = true;

      if (do_matlab)
        {
          std::ofstream out ("histo.m");

          out << "% This is a sample histogram plot for Matlab." << std::endl;
          out << "bin_members = [" << std::endl;
          for (unsigned int i=0; i<n_bins; i++)
            out << static_cast<Real>(histogram[i]) / static_cast<Real>(mesh.n_elem())
                << std::endl;
          out << "];" << std::endl;

          std::vector<Real> bin_coords(n_bins);
          const Real max   = *(std::max_element(sv.begin(), sv.end()));
          const Real min   = *(std::min_element(sv.begin(), sv.end()));
          const Real delta = (max - min) / static_cast<Real>(n_bins);
          for (unsigned int i=0; i<n_bins; i++)
            bin_coords[i] = min + (i * delta) + delta / 2.0 ;

          out << "bin_coords = [" << std::endl;
          for (unsigned int i=0; i<n_bins; i++)
            out << bin_coords[i] << std::endl;
          out << "];" << std::endl;

          out << "bar(bin_coords, bin_members, 1);" << std::endl;
          out << "hold on" << std::endl;
          out << "plot (bin_coords, 0, 'kx');" << std::endl;
          out << "xlabel('Quality (0=Worst, 1=Best)');" << std::endl;
          out << "ylabel('Percentage of elements in each bin');" << std::endl;
          out << "axis([" << min << "," << max << ",0, max(bin_members)]);" << std::endl;

          out << "title('" << Quality::name(quality_type) << "');" << std::endl;

        }
    }


  /**
   * Possibly convert all linear
   * elements to second-order counterparts
   */
  if (convert_second_order > 0)
    {
      bool second_order_mode = true;
      std:: string message = "Converting elements to second order counterparts";
      if (convert_second_order == 2)
        {
          second_order_mode = false;
          message += ", lower version: Quad4 -> Quad8, not Quad9";
        }

      else if (convert_second_order == 22)
        {
          second_order_mode = true;
          message += ", highest version: Quad4 -> Quad9";
        }

      else
        libmesh_error_msg("Invalid value, convert_second_order = " << convert_second_order);

      if (verbose)
        libMesh::out << message << std::endl;

      mesh.all_second_order(second_order_mode);

      if (verbose)
        {
          mesh.print_info();
          mesh.get_boundary_info().print_summary();
        }
    }


#ifdef LIBMESH_ENABLE_AMR

  /**
   * Possibly refine the mesh
   */
  if (n_rsteps > 0)
    {
      if (verbose)
        libMesh::out << "Refining the mesh "
                     << n_rsteps << " times"
                     << std::endl;

      MeshRefinement mesh_refinement (mesh);
      mesh_refinement.uniformly_refine(n_rsteps);

      if (verbose)
        {
          mesh.print_info();
          mesh.get_boundary_info().print_summary();
        }
    }


  /**
   * Possibly distort the mesh
   */
  if (dist_fact > 0.)
    {
      libMesh::out << "Distoring the mesh by a factor of "
                   << dist_fact
                   << std::endl;

      MeshTools::Modification::distort(mesh,dist_fact);
    };


  /*
    char filechar[81];
    sprintf(filechar,"%s-%04d.plt", "out", 0);
    std::string oname(filechar);

    mesh.write(oname);

    for (unsigned int step=0; step<100; step++)
    {
    //        const Real x = .5 + .25*cos((((Real) step)/100.)*3.1415927);
    //        const Real y = .5 + .25*sin((((Real) step)/100.)*3.1415927);
    const Real x = 2.5*cos((((Real) step)/100.)*3.1415927);
    const Real y = 2.5*sin((((Real) step)/100.)*3.1415927);

    const Point p(x,y);

    for (unsigned int e=0; e<mesh.n_elem(); e++)
    if (mesh.elem(e)->active())
    mesh.elem(e)->set_refinement_flag() = -1;



    for (unsigned int e=0; e<mesh.n_elem(); e++)
    if (mesh.elem(e)->active())
    {
    const Point diff = mesh.elem(e)->centroid(mesh) - p;

    if (diff.size() < .5)
    {
    if (mesh.elem(e)->level() < 4)
    mesh.elem(e)->set_refinement_flag() = 1;
    else if (mesh.elem(e)->level() == 4)
    mesh.elem(e)->set_refinement_flag() = 0;
    }
    }


    mesh.mesh_refinement.refine_and_coarsen_elements();

    char filechar[81];
    sprintf(filechar,"%s-%04d.plt", "out", step+1);
    std::string oname(filechar);

    mesh.write(oname);
    }
  */

#endif



  //     /**
  //      * Possibly partition the mesh
  //      */
  if (n_subdomains > 1)
    mesh.partition(n_subdomains);


  /**
   * Possibly write the mesh
   */
  {
    if (names.size() >= 2)
      {
        /*
         * When the mesh got refined, it is likely that
         * the user does _not_ want to write also
         * the coarse elements, but only the active ones.
         * Use Mesh::create_submesh() to create a mesh
         * of only active elements, and then write _this_
         * new mesh.
         */
        if (n_rsteps > 0)
          {
            if (verbose)
              libMesh::out << " Mesh got refined, will write only _active_ elements." << std::endl;

            Mesh new_mesh (init.comm(), mesh.mesh_dimension());

            construct_mesh_of_active_elements(new_mesh, mesh);

            // now write the new_mesh
            if (names.size() == 2)
              new_mesh.write(names[1]);
            else if (names.size() == 3)
              new_mesh.write(names[1], soln, var_names);
            else
              libmesh_error_msg("Invalid names.size() = " << names.size());
          }
        else
          {
            if (names.size() == 2)
              mesh.write(names[1]);
            else if (names.size() == 3)
              mesh.write(names[1], soln, var_names);
            else
              libmesh_error_msg("Invalid names.size() = " << names.size());
          }



        /**
         * Possibly write the BCs
         */
        if (write_bndry != BM_DISABLED)
          {
            BoundaryMesh boundary_mesh
              (mesh.comm(), cast_int<unsigned char>(mesh.mesh_dimension()-1));
            MeshData boundary_mesh_data (boundary_mesh);

            std::string boundary_name = "bndry_";
            boundary_name += names[1];

            if (write_bndry == BM_MESH_ONLY)
              mesh.get_boundary_info().sync(boundary_mesh);

            else if  (write_bndry == BM_WITH_MESHDATA)
              mesh.get_boundary_info().sync(boundary_mesh, &boundary_mesh_data, &mesh_data);

            else
              libmesh_error_msg("Invalid value write_bndry = " << write_bndry);

            if (names.size() == 2)
              boundary_mesh.write(boundary_name);
            else if (names.size() == 3)
              boundary_mesh.write(boundary_name, soln, var_names);
          }
      }
  };

  /*
    libMesh::out << "Infinite loop, look at memory footprint" << std::endl;
    for (;;)
    ;
  */

  return 0;
}
示例#21
0
// Begin the main program.
int main (int argc, char ** argv)
{
  // Initialize libMesh, like in example 2.
  LibMeshInit init (argc, argv);

  // This example requires Infinite Elements
#ifndef LIBMESH_ENABLE_INFINITE_ELEMENTS
  libmesh_example_requires(false, "--enable-ifem");
#else

  // Skip this 3D example if libMesh was compiled as 1D/2D-only.
  libmesh_example_requires(3 <= LIBMESH_DIM, "3D support");

  // Tell the user what we are doing.
  libMesh::out << "Running ex6 with dim = 3" << std::endl << std::endl;

  // Create a serialized mesh, distributed across the default MPI
  // communicator.
  // InfElemBuilder still requires some updates to be DistributedMesh
  // compatible

  ReplicatedMesh mesh(init.comm());

  // Use the internal mesh generator to create elements
  // on the square [-1,1]^3, of type Hex8.
  MeshTools::Generation::build_cube (mesh,
                                     4, 4, 4,
                                     -1., 1.,
                                     -1., 1.,
                                     -1., 1.,
                                     HEX8);

  // Print information about the mesh to the screen.
  mesh.print_info();

  // Write the mesh before the infinite elements are added
#ifdef LIBMESH_HAVE_EXODUS_API
  ExodusII_IO(mesh).write ("orig_mesh.e");
#endif

  // Normally, when a mesh is imported or created in
  // libMesh, only conventional elements exist.  The infinite
  // elements used here, however, require prescribed
  // nodal locations (with specified distances from an imaginary
  // origin) and configurations that a conventional mesh creator
  // in general does not offer.  Therefore, an efficient method
  // for building infinite elements is offered.  It can account
  // for symmetry planes and creates infinite elements in a fully
  // automatic way.
  //
  // Right now, the simplified interface is used, automatically
  // determining the origin.  Check MeshBase for a generalized
  // method that can even return the element faces of interior
  // vibrating surfaces.  The bool determines whether to be
  // verbose.
  InfElemBuilder builder(mesh);
  builder.build_inf_elem(true);

  // Reassign subdomain_id() of all infinite elements.
  // Otherwise, the exodus-api will fail on the mesh.
  MeshBase::element_iterator       elem_it  = mesh.elements_begin();
  const MeshBase::element_iterator elem_end = mesh.elements_end();
  for (; elem_it != elem_end; ++elem_it)
    {
      Elem* elem = *elem_it;
      if(elem->infinite())
        {
          elem->subdomain_id() = 1;
        }
    }



  // Print information about the mesh to the screen.
  mesh.print_info();

  // Write the mesh with the infinite elements added.
  // Compare this to the original mesh.
#ifdef LIBMESH_HAVE_EXODUS_API
  ExodusII_IO(mesh).write ("ifems_added.e");
#endif

  // After building infinite elements, we have to let
  // the elements find their neighbors again.
  mesh.find_neighbors();

  // Create an equation systems object, where ThinSystem
  // offers only the crucial functionality for solving a
  // system.  Use ThinSystem when you want the sleekest
  // system possible.
  EquationSystems equation_systems (mesh);

  // Declare the system and its variables.
  // Create a system named "Wave".  This can
  // be a simple, steady system
  equation_systems.add_system<LinearImplicitSystem> ("Wave");

  // Create an FEType describing the approximation
  // characteristics of the InfFE object.  Note that
  // the constructor automatically defaults to some
  // sensible values.  But use FIRST order
  // approximation.
  FEType fe_type(FIRST);

  // Add the variable "p" to "Wave".  Note that there exist
  // various approaches in adding variables.  In example 3,
  // add_variable took the order of approximation and used
  // default values for the FEFamily, while here the FEType
  // is used.
  equation_systems.get_system("Wave").add_variable("p", fe_type);

  // Give the system a pointer to the matrix assembly
  // function.
  equation_systems.get_system("Wave").attach_assemble_function (assemble_wave);

  // Set the speed of sound and fluid density
  // as EquationSystems parameter,
  // so that assemble_wave() can access it.
  equation_systems.parameters.set<Real>("speed")         = 1.;
  equation_systems.parameters.set<Real>("fluid density") = 1.;

  // Initialize the data structures for the equation system.
  equation_systems.init();

  // Prints information about the system to the screen.
  equation_systems.print_info();

  // Solve the system "Wave".
  equation_systems.get_system("Wave").solve();

  // Write the whole EquationSystems object to file.
  // For infinite elements, the concept of nodal_soln()
  // is not applicable. Therefore, writing the mesh in
  // some format @e always gives all-zero results at
  // the nodes of the infinite elements.  Instead,
  // use the FEInterface::compute_data() methods to
  // determine physically correct results within an
  // infinite element.
  equation_systems.write ("eqn_sys.dat", WRITE);

  // All done.
  return 0;

#endif // else part of ifndef LIBMESH_ENABLE_INFINITE_ELEMENTS
}
示例#22
0
void ParmetisPartitioner::build_graph (const MeshBase & mesh)
{
  // build the graph in distributed CSR format.  Note that
  // the edges in the graph will correspond to
  // face neighbors
  const dof_id_type n_active_local_elem  = mesh.n_active_local_elem();

  // If we have boundary elements in this mesh, we want to account for
  // the connectivity between them and interior elements.  We can find
  // interior elements from boundary elements, but we need to build up
  // a lookup map to do the reverse.

  typedef LIBMESH_BEST_UNORDERED_MULTIMAP<const Elem *, const Elem *>
    map_type;
  map_type interior_to_boundary_map;

  {
    MeshBase::const_element_iterator       elem_it  = mesh.active_elements_begin();
    const MeshBase::const_element_iterator elem_end = mesh.active_elements_end();

    for (; elem_it != elem_end; ++elem_it)
      {
        const Elem * elem = *elem_it;

        // If we don't have an interior_parent then there's nothing to look us
        // up.
        if ((elem->dim() >= LIBMESH_DIM) ||
            !elem->interior_parent())
          continue;

        // get all relevant interior elements
        std::set<const Elem *> neighbor_set;
        elem->find_interior_neighbors(neighbor_set);

        std::set<const Elem *>::iterator n_it = neighbor_set.begin();
        for (; n_it != neighbor_set.end(); ++n_it)
          {
            // FIXME - non-const versions of the Elem set methods
            // would be nice
            Elem * neighbor = const_cast<Elem *>(*n_it);

#if defined(LIBMESH_HAVE_UNORDERED_MULTIMAP) || \
  defined(LIBMESH_HAVE_TR1_UNORDERED_MAP) ||    \
  defined(LIBMESH_HAVE_HASH_MAP) ||             \
  defined(LIBMESH_HAVE_EXT_HASH_MAP)
            interior_to_boundary_map.insert
              (std::make_pair(neighbor, elem));
#else
            interior_to_boundary_map.insert
              (interior_to_boundary_map.begin(),
               std::make_pair(neighbor, elem));
#endif
          }
      }
  }

#ifdef LIBMESH_ENABLE_AMR
  std::vector<const Elem *> neighbors_offspring;
#endif

  std::vector<std::vector<dof_id_type> > graph(n_active_local_elem);
  dof_id_type graph_size=0;

  const dof_id_type first_local_elem = _pmetis->vtxdist[mesh.processor_id()];

  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)
    {
      const Elem * elem = *elem_it;

      libmesh_assert (_global_index_by_pid_map.count(elem->id()));
      const dof_id_type global_index_by_pid =
        _global_index_by_pid_map[elem->id()];

      const dof_id_type local_index =
        global_index_by_pid - first_local_elem;
      libmesh_assert_less (local_index, n_active_local_elem);

      std::vector<dof_id_type> & graph_row = graph[local_index];

      // Loop over the element's neighbors.  An element
      // adjacency corresponds to a face neighbor
      for (unsigned int ms=0; ms<elem->n_neighbors(); ms++)
        {
          const Elem * neighbor = elem->neighbor(ms);

          if (neighbor != libmesh_nullptr)
            {
              // If the neighbor is active treat it
              // as a connection
              if (neighbor->active())
                {
                  libmesh_assert(_global_index_by_pid_map.count(neighbor->id()));
                  const dof_id_type neighbor_global_index_by_pid =
                    _global_index_by_pid_map[neighbor->id()];

                  graph_row.push_back(neighbor_global_index_by_pid);
                  graph_size++;
                }

#ifdef LIBMESH_ENABLE_AMR

              // Otherwise we need to find all of the
              // neighbor's children that are connected to
              // us and add them
              else
                {
                  // The side of the neighbor to which
                  // we are connected
                  const unsigned int ns =
                    neighbor->which_neighbor_am_i (elem);
                  libmesh_assert_less (ns, neighbor->n_neighbors());

                  // Get all the active children (& grandchildren, etc...)
                  // of the neighbor

                  // FIXME - this is the wrong thing, since we
                  // should be getting the active family tree on
                  // our side only.  But adding too many graph
                  // links may cause hanging nodes to tend to be
                  // on partition interiors, which would reduce
                  // communication overhead for constraint
                  // equations, so we'll leave it.

                  neighbor->active_family_tree (neighbors_offspring);

                  // Get all the neighbor's children that
                  // live on that side and are thus connected
                  // to us
                  for (unsigned int nc=0; nc<neighbors_offspring.size(); nc++)
                    {
                      const Elem * child =
                        neighbors_offspring[nc];

                      // This does not assume a level-1 mesh.
                      // Note that since children have sides numbered
                      // coincident with the parent then this is a sufficient test.
                      if (child->neighbor(ns) == elem)
                        {
                          libmesh_assert (child->active());
                          libmesh_assert (_global_index_by_pid_map.count(child->id()));
                          const dof_id_type child_global_index_by_pid =
                            _global_index_by_pid_map[child->id()];

                          graph_row.push_back(child_global_index_by_pid);
                          graph_size++;
                        }
                    }
                }

#endif /* ifdef LIBMESH_ENABLE_AMR */


            }
        }

      if ((elem->dim() < LIBMESH_DIM) &&
          elem->interior_parent())
        {
          // get all relevant interior elements
          std::set<const Elem *> neighbor_set;
          elem->find_interior_neighbors(neighbor_set);

          std::set<const Elem *>::iterator n_it = neighbor_set.begin();
          for (; n_it != neighbor_set.end(); ++n_it)
            {
              // FIXME - non-const versions of the Elem set methods
              // would be nice
              Elem * neighbor = const_cast<Elem *>(*n_it);

              const dof_id_type neighbor_global_index_by_pid =
                _global_index_by_pid_map[neighbor->id()];

              graph_row.push_back(neighbor_global_index_by_pid);
              graph_size++;
            }
        }

      // Check for any boundary neighbors
      typedef map_type::iterator map_it_type;
      std::pair<map_it_type, map_it_type>
        bounds = interior_to_boundary_map.equal_range(elem);

      for (map_it_type it = bounds.first; it != bounds.second; ++it)
        {
          const Elem * neighbor = it->second;

          const dof_id_type neighbor_global_index_by_pid =
            _global_index_by_pid_map[neighbor->id()];

          graph_row.push_back(neighbor_global_index_by_pid);
          graph_size++;
        }
    }

  // Reserve space in the adjacency array
  _pmetis->xadj.clear();
  _pmetis->xadj.reserve (n_active_local_elem + 1);
  _pmetis->adjncy.clear();
  _pmetis->adjncy.reserve (graph_size);

  for (std::size_t r=0; r<graph.size(); r++)
    {
      _pmetis->xadj.push_back(_pmetis->adjncy.size());
      std::vector<dof_id_type> graph_row; // build this emtpy
      graph_row.swap(graph[r]); // this will deallocate at the end of scope
      _pmetis->adjncy.insert(_pmetis->adjncy.end(),
                             graph_row.begin(),
                             graph_row.end());
    }

  // The end of the adjacency array for the last elem
  _pmetis->xadj.push_back(_pmetis->adjncy.size());

  libmesh_assert_equal_to (_pmetis->xadj.size(), n_active_local_elem+1);
  libmesh_assert_equal_to (_pmetis->adjncy.size(), graph_size);
}
  void setUp() {
#if LIBMESH_DIM > 2
    mesh.reset(new Mesh(*TestCommWorld));
    MeshTools::Generation::build_cube(*mesh, 1, 1, 1);
    es.reset(new EquationSystems(*mesh));
    sys = &(es->add_system<System> ("SimpleSystem"));
    sys->add_variable("x2");
    sys->add_variable("x3");
    sys->add_variable("c05");
    sys->add_variable("y4");
    sys->add_variable("xy");
    sys->add_variable("yz");
    sys->add_variable("xyz");

    es->init();

    NumericVector<Number> & sol = *sys->solution;
    Elem *elem = mesh->query_elem_ptr(0);

    if (elem && elem->processor_id() == TestCommWorld->rank())
      {
        // Set x2 = 2*x
        sol.set(elem->node_ref(1).dof_number(0,0,0), 2);
        sol.set(elem->node_ref(2).dof_number(0,0,0), 2);
        sol.set(elem->node_ref(5).dof_number(0,0,0), 2);
        sol.set(elem->node_ref(6).dof_number(0,0,0), 2);

        // Set x3 = 3*x
        sol.set(elem->node_ref(1).dof_number(0,1,0), 3);
        sol.set(elem->node_ref(2).dof_number(0,1,0), 3);
        sol.set(elem->node_ref(5).dof_number(0,1,0), 3);
        sol.set(elem->node_ref(6).dof_number(0,1,0), 3);

        // Set c05 = 0.5
        sol.set(elem->node_ref(0).dof_number(0,2,0), 0.5);
        sol.set(elem->node_ref(1).dof_number(0,2,0), 0.5);
        sol.set(elem->node_ref(2).dof_number(0,2,0), 0.5);
        sol.set(elem->node_ref(3).dof_number(0,2,0), 0.5);
        sol.set(elem->node_ref(4).dof_number(0,2,0), 0.5);
        sol.set(elem->node_ref(5).dof_number(0,2,0), 0.5);
        sol.set(elem->node_ref(6).dof_number(0,2,0), 0.5);
        sol.set(elem->node_ref(7).dof_number(0,2,0), 0.5);

        // Set y4 = 4*y
        sol.set(elem->node_ref(2).dof_number(0,3,0), 4);
        sol.set(elem->node_ref(3).dof_number(0,3,0), 4);
        sol.set(elem->node_ref(6).dof_number(0,3,0), 4);
        sol.set(elem->node_ref(7).dof_number(0,3,0), 4);

        // Set xy = x*y
        sol.set(elem->node_ref(2).dof_number(0,4,0), 1);
        sol.set(elem->node_ref(6).dof_number(0,4,0), 1);

        // Set yz = y*z
        sol.set(elem->node_ref(6).dof_number(0,5,0), 1);
        sol.set(elem->node_ref(7).dof_number(0,5,0), 1);

        // Set xyz = x*y*z
        sol.set(elem->node_ref(6).dof_number(0,6,0), 1);
      }

    sol.close();
    sys->update();

    c.reset(new FEMContext(*sys));
    s.reset(new FEMContext(*sys));
    if (elem && elem->processor_id() == TestCommWorld->rank())
      {
        c->pre_fe_reinit(*sys, elem);
        c->elem_fe_reinit();
        s->pre_fe_reinit(*sys, elem);
        s->side = 3;
        s->side_fe_reinit();
      }
#endif
  }
示例#24
0
void unpack(std::vector<int>::const_iterator in,
            Elem** out,
            MeshBase* mesh)
{
#ifndef NDEBUG
  const std::vector<int>::const_iterator original_in = in;

  const int incoming_header = *in++;
  libmesh_assert (incoming_header == elem_magic_header);
#endif

  // int 0: level
  const unsigned int level =
    static_cast<unsigned int>(*in++);

#ifdef LIBMESH_ENABLE_AMR
  // int 1: p level
  const unsigned int p_level =
    static_cast<unsigned int>(*in++);

  // int 2: refinement flag
  const int rflag = *in++;
  libmesh_assert(rflag >= 0);
  libmesh_assert(rflag < Elem::INVALID_REFINEMENTSTATE);
  const Elem::RefinementState refinement_flag =
    static_cast<Elem::RefinementState>(rflag);

  // int 3: p refinement flag
  const int pflag = *in++;
  libmesh_assert(pflag >= 0);
  libmesh_assert(pflag < Elem::INVALID_REFINEMENTSTATE);
  const Elem::RefinementState p_refinement_flag =
    static_cast<Elem::RefinementState>(pflag);
#else
  in += 3;
#endif // LIBMESH_ENABLE_AMR

  // int 4: element type
  const int typeint = *in++;
  libmesh_assert(typeint >= 0);
  libmesh_assert(typeint < INVALID_ELEM);
  const ElemType type =
    static_cast<ElemType>(typeint);

  const unsigned int n_nodes = 
    Elem::type_to_n_nodes_map[type];

  // int 5: processor id
  const unsigned int processor_id = 
    static_cast<unsigned int>(*in++);
  libmesh_assert (processor_id < libMesh::n_processors() ||
                  processor_id == DofObject::invalid_processor_id);

  // int 6: subdomain id
  const unsigned int subdomain_id = 
    static_cast<unsigned int>(*in++);

  // int 7: dof object id
  const unsigned int id = 
    static_cast<unsigned int>(*in++);
  libmesh_assert (id != DofObject::invalid_id);

#ifdef LIBMESH_ENABLE_AMR
  // int 8: parent dof object id
  const unsigned int parent_id = 
    static_cast<unsigned int>(*in++);
  libmesh_assert (level == 0 || parent_id != DofObject::invalid_id);
  libmesh_assert (level != 0 || parent_id == DofObject::invalid_id);

  // int 9: local child id
  const unsigned int which_child_am_i = 
    static_cast<unsigned int>(*in++);
#else
  in += 2;
#endif // LIBMESH_ENABLE_AMR

  // Make sure we don't miscount above when adding the "magic" header
  // plus the real data header
  libmesh_assert(in - original_in == header_size + 1);

  Elem *elem = mesh->query_elem(id);

  // if we already have this element, make sure its
  // properties match, and update any missing neighbor
  // links, but then go on
  if (elem) 
    {
      libmesh_assert (elem->level()             == level);
      libmesh_assert (elem->id()                == id);
      libmesh_assert (elem->processor_id()      == processor_id);
      libmesh_assert (elem->subdomain_id()      == subdomain_id);
      libmesh_assert (elem->type()              == type);
      libmesh_assert (elem->n_nodes()           == n_nodes);

#ifndef NDEBUG
      // All our nodes should be correct
      for (unsigned int i=0; i != n_nodes; ++i)
        libmesh_assert(elem->node(i) == 
                       static_cast<unsigned int>(*in++));
#else
      in += n_nodes;
#endif

#ifdef LIBMESH_ENABLE_AMR
      libmesh_assert (elem->p_level()           == p_level);
      libmesh_assert (elem->refinement_flag()   == refinement_flag);
      libmesh_assert (elem->p_refinement_flag() == p_refinement_flag);

      libmesh_assert (!level || elem->parent() != NULL);
      libmesh_assert (!level || elem->parent()->id() == parent_id);
      libmesh_assert (!level || elem->parent()->child(which_child_am_i) == elem);
#endif

      // Our neighbor links should be "close to" correct - we may have
      // to update them, but we can check for some inconsistencies.
      for (unsigned int n=0; n != elem->n_neighbors(); ++n)
        {
          const unsigned int neighbor_id =
            static_cast<unsigned int>(*in++);

	  // If the sending processor sees a domain boundary here,
	  // we'd better agree.
          if (neighbor_id == DofObject::invalid_id)
            {
              libmesh_assert(elem->neighbor(n) == NULL);
              continue;
            }

	  // If the sending processor has a remote_elem neighbor here,
	  // then all we know is that we'd better *not* have a domain
	  // boundary.
          if (neighbor_id == remote_elem->id())
            {
              libmesh_assert(elem->neighbor(n) != NULL);
              continue;
            }

          Elem *neigh = mesh->query_elem(neighbor_id);

          // The sending processor sees a neighbor here, so if we
          // don't have that neighboring element, then we'd better
          // have a remote_elem signifying that fact.
          if (!neigh)
            {
              libmesh_assert(elem->neighbor(n) == remote_elem);
              continue;
            }

          // The sending processor has a neighbor here, and we have
          // that element, but that does *NOT* mean we're already
	  // linking to it.  Perhaps we initially received both elem
	  // and neigh from processors on which their mutual link was
	  // remote?
          libmesh_assert(elem->neighbor(n) == neigh ||
			 elem->neighbor(n) == remote_elem);

	  // If the link was originally remote, we should update it,
	  // and make sure the appropriate parts of its family link
	  // back to us.
	  if (elem->neighbor(n) == remote_elem)
            {
              elem->set_neighbor(n, neigh); 

              elem->make_links_to_me_local(n); 
	    }
	}

      // FIXME: We should add some debug mode tests to ensure that the
      // encoded indexing and boundary conditions are consistent.
    }
  else
    {
      // We don't already have the element, so we need to create it.

      // Find the parent if necessary
      Elem *parent = NULL;
#ifdef LIBMESH_ENABLE_AMR
      // Find a child element's parent
      if (level > 0)
        {
	  // Note that we must be very careful to construct the send
	  // connectivity so that parents are encountered before
	  // children.  If we get here and can't find the parent that
	  // is a fatal error.
          parent = mesh->elem(parent_id);
        }
      // Or assert that the sending processor sees no parent
      else
        libmesh_assert (parent_id == static_cast<unsigned int>(-1));
#else
      // No non-level-0 elements without AMR
      libmesh_assert (level == 0);
#endif

      elem = Elem::build(type,parent).release();
      libmesh_assert (elem);

#ifdef LIBMESH_ENABLE_AMR
      if (level != 0)
        {
          // Since this is a newly created element, the parent must
          // have previously thought of this child as a remote element.
          libmesh_assert (parent->child(which_child_am_i) == remote_elem);

          parent->add_child(elem, which_child_am_i);
        }

      // Assign the refinement flags and levels
      elem->set_p_level(p_level);
      elem->set_refinement_flag(refinement_flag);
      elem->set_p_refinement_flag(p_refinement_flag);
      libmesh_assert (elem->level() == level);

      // If this element definitely should have children, assign
      // remote_elem to all of them for now, for consistency.  Later
      // unpacked elements may overwrite that.
      if (!elem->active())
        for (unsigned int c=0; c != elem->n_children(); ++c)
          elem->add_child(const_cast<RemoteElem*>(remote_elem), c);

#endif // LIBMESH_ENABLE_AMR

      // Assign the IDs
      elem->subdomain_id() = subdomain_id;
      elem->processor_id() = processor_id;
      elem->set_id()       = id;

      // Assign the connectivity
      libmesh_assert (elem->n_nodes() == n_nodes);

      for (unsigned int n=0; n != n_nodes; n++)
        elem->set_node(n) =
          mesh->node_ptr
	    (static_cast<unsigned int>(*in++));

      for (unsigned int n=0; n<elem->n_neighbors(); n++)
        {
          const unsigned int neighbor_id =
            static_cast<unsigned int>(*in++);

          if (neighbor_id == DofObject::invalid_id)
	    continue;

          // We may be unpacking an element that was a ghost element on the
          // sender, in which case the element's neighbors may not all be
          // known by the packed element.  We'll have to set such
          // neighbors to remote_elem ourselves and wait for a later
          // packed element to give us better information.
          if (neighbor_id == remote_elem->id())
            {
              elem->set_neighbor(n, const_cast<RemoteElem*>(remote_elem));
	      continue;
	    }

          // If we don't have the neighbor element, then it's a
          // remote_elem until we get it.
          Elem *neigh = mesh->query_elem(neighbor_id);
          if (!neigh)
            {
              elem->set_neighbor(n, const_cast<RemoteElem*>(remote_elem));
	      continue;
	    }

          // If we have the neighbor element, then link to it, and
          // make sure the appropriate parts of its family link back
          // to us.
          elem->set_neighbor(n, neigh);

          elem->make_links_to_me_local(n);
        }

      elem->unpack_indexing(in);
    }

  in += elem->packed_indexing_size();

  // If this is a coarse element,
  // add any element side boundary condition ids
  if (level == 0)
    for (unsigned int s = 0; s != elem->n_sides(); ++s)
      {
        const int num_bcs = *in++;
        libmesh_assert (num_bcs >= 0);

        for(int bc_it=0; bc_it < num_bcs; bc_it++)
          mesh->boundary_info->add_side (elem, s, *in++);
      }

  // Return the new element
  *out = elem;
}
示例#25
0
UniquePtr<Elem> InfHex8::build_side (const unsigned int i,
                                     bool proxy) const
{
  libmesh_assert_less (i, this->n_sides());

  if (proxy)
    {
      switch (i)
        {
          // base
        case 0:
          return UniquePtr<Elem>(new Side<Quad4,InfHex8>(this,i));

          // ifem sides
        case 1:
        case 2:
        case 3:
        case 4:
          return UniquePtr<Elem>(new Side<InfQuad4,InfHex8>(this,i));

        default:
          libmesh_error_msg("Invalid side i = " << i);
        }
    }

  else
    {
      // Create NULL pointer to be initialized, returned later.
      Elem * face = libmesh_nullptr;

      // Think of a unit cube: (-1,1) x (-1,1) x (1,1)
      switch (i)
        {
        case 0: // the base face
          {
            face = new Quad4;
            break;
          }

          // connecting to another infinite element
        case 1:
        case 2:
        case 3:
        case 4:
          {
            face = new InfQuad4;
            break;
          }

        default:
          libmesh_error_msg("Invalid side i = " << i);
        }

      face->subdomain_id() = this->subdomain_id();

      // Set the nodes
      for (unsigned n=0; n<face->n_nodes(); ++n)
        face->set_node(n) = this->get_node(InfHex8::side_nodes_map[i][n]);

      return UniquePtr<Elem>(face);
    }

  libmesh_error_msg("We'll never get here!");
  return UniquePtr<Elem>();
}
示例#26
0
Elem *
Packing<Elem *>::unpack (std::vector<largest_id_type>::const_iterator in,
                         MeshBase * mesh)
{
#ifndef NDEBUG
  const std::vector<largest_id_type>::const_iterator original_in = in;

  const largest_id_type incoming_header = *in++;
  libmesh_assert_equal_to (incoming_header, elem_magic_header);
#endif

  // int 0: level
  const unsigned int level =
    cast_int<unsigned int>(*in++);

#ifdef LIBMESH_ENABLE_AMR
  // int 1: p level
  const unsigned int p_level =
    cast_int<unsigned int>(*in++);

  // int 2: refinement flag and encoded has_children
  const int rflag = cast_int<int>(*in++);
  const int invalid_rflag =
    cast_int<int>(Elem::INVALID_REFINEMENTSTATE);
  libmesh_assert_greater_equal (rflag, 0);

  libmesh_assert_less (rflag, invalid_rflag*2+1);

  const bool has_children = (rflag > invalid_rflag);

  const Elem::RefinementState refinement_flag = has_children ?
    cast_int<Elem::RefinementState>(rflag - invalid_rflag - 1) :
    cast_int<Elem::RefinementState>(rflag);

  // int 3: p refinement flag
  const int pflag = cast_int<int>(*in++);
  libmesh_assert_greater_equal (pflag, 0);
  libmesh_assert_less (pflag, Elem::INVALID_REFINEMENTSTATE);
  const Elem::RefinementState p_refinement_flag =
    cast_int<Elem::RefinementState>(pflag);
#else
  in += 3;
#endif // LIBMESH_ENABLE_AMR

  // int 4: element type
  const int typeint = cast_int<int>(*in++);
  libmesh_assert_greater_equal (typeint, 0);
  libmesh_assert_less (typeint, INVALID_ELEM);
  const ElemType type =
    cast_int<ElemType>(typeint);

  const unsigned int n_nodes =
    Elem::type_to_n_nodes_map[type];

  // int 5: processor id
  const processor_id_type processor_id =
    cast_int<processor_id_type>(*in++);
  libmesh_assert (processor_id < mesh->n_processors() ||
                  processor_id == DofObject::invalid_processor_id);

  // int 6: subdomain id
  const subdomain_id_type subdomain_id =
    cast_int<subdomain_id_type>(*in++);

  // int 7: dof object id
  const dof_id_type id =
    cast_int<dof_id_type>(*in++);
  libmesh_assert_not_equal_to (id, DofObject::invalid_id);

#ifdef LIBMESH_ENABLE_UNIQUE_ID
  // int 8: dof object unique id
  const unique_id_type unique_id =
    cast_int<unique_id_type>(*in++);
#endif

#ifdef LIBMESH_ENABLE_AMR
  // int 9: parent dof object id.
  // Note: If level==0, then (*in) == invalid_id.  In
  // this case, the equality check in cast_int<unsigned>(*in) will
  // never succeed.  Therefore, we should only attempt the more
  // rigorous cast verification in cases where level != 0.
  const dof_id_type parent_id =
    (level == 0)
    ? static_cast<dof_id_type>(*in++)
    : cast_int<dof_id_type>(*in++);
  libmesh_assert (level == 0 || parent_id != DofObject::invalid_id);
  libmesh_assert (level != 0 || parent_id == DofObject::invalid_id);

  // int 10: local child id
  // Note: If level==0, then which_child_am_i is not valid, so don't
  // do the more rigorous cast verification.
  const unsigned int which_child_am_i =
    (level == 0)
    ? static_cast<unsigned int>(*in++)
    : cast_int<unsigned int>(*in++);
#else
  in += 2;
#endif // LIBMESH_ENABLE_AMR

  const dof_id_type interior_parent_id =
    static_cast<dof_id_type>(*in++);

  // Make sure we don't miscount above when adding the "magic" header
  // plus the real data header
  libmesh_assert_equal_to (in - original_in, header_size + 1);

  Elem * elem = mesh->query_elem_ptr(id);

  // if we already have this element, make sure its
  // properties match, and update any missing neighbor
  // links, but then go on
  if (elem)
    {
      libmesh_assert_equal_to (elem->level(), level);
      libmesh_assert_equal_to (elem->id(), id);
      //#ifdef LIBMESH_ENABLE_UNIQUE_ID
      // No check for unique id sanity
      //#endif
      libmesh_assert_equal_to (elem->processor_id(), processor_id);
      libmesh_assert_equal_to (elem->subdomain_id(), subdomain_id);
      libmesh_assert_equal_to (elem->type(), type);
      libmesh_assert_equal_to (elem->n_nodes(), n_nodes);

#ifndef NDEBUG
      // All our nodes should be correct
      for (unsigned int i=0; i != n_nodes; ++i)
        libmesh_assert(elem->node_id(i) ==
                       cast_int<dof_id_type>(*in++));
#else
      in += n_nodes;
#endif

#ifdef LIBMESH_ENABLE_AMR
      libmesh_assert_equal_to (elem->refinement_flag(), refinement_flag);
      libmesh_assert_equal_to (elem->has_children(), has_children);

#ifdef DEBUG
      if (elem->active())
        {
          libmesh_assert_equal_to (elem->p_level(), p_level);
          libmesh_assert_equal_to (elem->p_refinement_flag(), p_refinement_flag);
        }
#endif

      libmesh_assert (!level || elem->parent() != libmesh_nullptr);
      libmesh_assert (!level || elem->parent()->id() == parent_id);
      libmesh_assert (!level || elem->parent()->child_ptr(which_child_am_i) == elem);
#endif
      // Our interior_parent link should be "close to" correct - we
      // may have to update it, but we can check for some
      // inconsistencies.
      {
        // If the sending processor sees no interior_parent here, we'd
        // better agree.
        if (interior_parent_id == DofObject::invalid_id)
          {
            if (elem->dim() < LIBMESH_DIM)
              libmesh_assert (!(elem->interior_parent()));
          }

        // If the sending processor has a remote_elem interior_parent,
        // then all we know is that we'd better have *some*
        // interior_parent
        else if (interior_parent_id == remote_elem->id())
          {
            libmesh_assert(elem->interior_parent());
          }
        else
          {
            Elem * ip = mesh->query_elem_ptr(interior_parent_id);

            // The sending processor sees an interior parent here, so
            // if we don't have that interior element, then we'd
            // better have a remote_elem signifying that fact.
            if (!ip)
              libmesh_assert_equal_to (elem->interior_parent(), remote_elem);
            else
              {
                // The sending processor has an interior_parent here,
                // and we have that element, but that does *NOT* mean
                // we're already linking to it.  Perhaps we initially
                // received elem from a processor on which the
                // interior_parent link was remote?
                libmesh_assert(elem->interior_parent() == ip ||
                               elem->interior_parent() == remote_elem);

                // If the link was originally remote, update it
                if (elem->interior_parent() == remote_elem)
                  {
                    elem->set_interior_parent(ip);
                  }
              }
          }
      }

      // Our neighbor links should be "close to" correct - we may have
      // to update a remote_elem link, and we can check for possible
      // inconsistencies along the way.
      //
      // For subactive elements, we don't bother keeping neighbor
      // links in good shape, so there's nothing we need to set or can
      // safely assert here.
      if (!elem->subactive())
        for (auto n : elem->side_index_range())
          {
            const dof_id_type neighbor_id =
              cast_int<dof_id_type>(*in++);

            // If the sending processor sees a domain boundary here,
            // we'd better agree.
            if (neighbor_id == DofObject::invalid_id)
              {
                libmesh_assert (!(elem->neighbor_ptr(n)));
                continue;
              }

            // If the sending processor has a remote_elem neighbor here,
            // then all we know is that we'd better *not* have a domain
            // boundary.
            if (neighbor_id == remote_elem->id())
              {
                libmesh_assert(elem->neighbor_ptr(n));
                continue;
              }

            Elem * neigh = mesh->query_elem_ptr(neighbor_id);

            // The sending processor sees a neighbor here, so if we
            // don't have that neighboring element, then we'd better
            // have a remote_elem signifying that fact.
            if (!neigh)
              {
                libmesh_assert_equal_to (elem->neighbor_ptr(n), remote_elem);
                continue;
              }

            // The sending processor has a neighbor here, and we have
            // that element, but that does *NOT* mean we're already
            // linking to it.  Perhaps we initially received both elem
            // and neigh from processors on which their mutual link was
            // remote?
            libmesh_assert(elem->neighbor_ptr(n) == neigh ||
                           elem->neighbor_ptr(n) == remote_elem);

            // If the link was originally remote, we should update it,
            // and make sure the appropriate parts of its family link
            // back to us.
            if (elem->neighbor_ptr(n) == remote_elem)
              {
                elem->set_neighbor(n, neigh);

                elem->make_links_to_me_local(n);
              }
          }

      // Our p level and refinement flags should be "close to" correct
      // if we're not an active element - we might have a p level
      // increased or decreased by changes in remote_elem children.
      //
      // But if we have remote_elem children, then we shouldn't be
      // doing a projection on this inactive element on this
      // processor, so we won't need correct p settings.  Couldn't
      // hurt to update, though.
#ifdef LIBMESH_ENABLE_AMR
      if (elem->processor_id() != mesh->processor_id())
        {
          elem->hack_p_level(p_level);
          elem->set_p_refinement_flag(p_refinement_flag);
        }
#endif // LIBMESH_ENABLE_AMR

      // FIXME: We should add some debug mode tests to ensure that the
      // encoded indexing and boundary conditions are consistent.
    }
  else
    {
      // We don't already have the element, so we need to create it.

      // Find the parent if necessary
      Elem * parent = libmesh_nullptr;
#ifdef LIBMESH_ENABLE_AMR
      // Find a child element's parent
      if (level > 0)
        {
          // Note that we must be very careful to construct the send
          // connectivity so that parents are encountered before
          // children.  If we get here and can't find the parent that
          // is a fatal error.
          parent = mesh->elem_ptr(parent_id);
        }
      // Or assert that the sending processor sees no parent
      else
        libmesh_assert_equal_to (parent_id, DofObject::invalid_id);
#else
      // No non-level-0 elements without AMR
      libmesh_assert_equal_to (level, 0);
#endif

      elem = Elem::build(type,parent).release();
      libmesh_assert (elem);

#ifdef LIBMESH_ENABLE_AMR
      if (level != 0)
        {
          // Since this is a newly created element, the parent must
          // have previously thought of this child as a remote element.
          libmesh_assert_equal_to (parent->child_ptr(which_child_am_i), remote_elem);

          parent->add_child(elem, which_child_am_i);
        }

      // Assign the refinement flags and levels
      elem->set_p_level(p_level);
      elem->set_refinement_flag(refinement_flag);
      elem->set_p_refinement_flag(p_refinement_flag);
      libmesh_assert_equal_to (elem->level(), level);

      // If this element should have children, assign remote_elem to
      // all of them for now, for consistency.  Later unpacked
      // elements may overwrite that.
      if (has_children)
        {
          const unsigned int nc = elem->n_children();
          for (unsigned int c=0; c != nc; ++c)
            elem->add_child(const_cast<RemoteElem *>(remote_elem), c);
        }

#endif // LIBMESH_ENABLE_AMR

      // Assign the IDs
      elem->subdomain_id()  = subdomain_id;
      elem->processor_id()  = processor_id;
      elem->set_id()        = id;
#ifdef LIBMESH_ENABLE_UNIQUE_ID
      elem->set_unique_id() = unique_id;
#endif

      // Assign the connectivity
      libmesh_assert_equal_to (elem->n_nodes(), n_nodes);

      for (unsigned int n=0; n != n_nodes; n++)
        elem->set_node(n) =
          mesh->node_ptr
          (cast_int<dof_id_type>(*in++));

      // Set interior_parent if found
      {
        // We may be unpacking an element that was a ghost element on the
        // sender, in which case the element's interior_parent may not be
        // known by the packed element.  We'll have to set such
        // interior_parents to remote_elem ourselves and wait for a
        // later packed element to give us better information.
        if (interior_parent_id == remote_elem->id())
          {
            elem->set_interior_parent
              (const_cast<RemoteElem *>(remote_elem));
          }
        else if (interior_parent_id != DofObject::invalid_id)
          {
            // If we don't have the interior parent element, then it's
            // a remote_elem until we get it.
            Elem * ip = mesh->query_elem_ptr(interior_parent_id);
            if (!ip )
              elem->set_interior_parent
                (const_cast<RemoteElem *>(remote_elem));
            else
              elem->set_interior_parent(ip);
          }
      }

      for (auto n : elem->side_index_range())
        {
          const dof_id_type neighbor_id =
            cast_int<dof_id_type>(*in++);

          if (neighbor_id == DofObject::invalid_id)
            continue;

          // We may be unpacking an element that was a ghost element on the
          // sender, in which case the element's neighbors may not all be
          // known by the packed element.  We'll have to set such
          // neighbors to remote_elem ourselves and wait for a later
          // packed element to give us better information.
          if (neighbor_id == remote_elem->id())
            {
              elem->set_neighbor(n, const_cast<RemoteElem *>(remote_elem));
              continue;
            }

          // If we don't have the neighbor element, then it's a
          // remote_elem until we get it.
          Elem * neigh = mesh->query_elem_ptr(neighbor_id);
          if (!neigh)
            {
              elem->set_neighbor(n, const_cast<RemoteElem *>(remote_elem));
              continue;
            }

          // If we have the neighbor element, then link to it, and
          // make sure the appropriate parts of its family link back
          // to us.
          elem->set_neighbor(n, neigh);

          elem->make_links_to_me_local(n);
        }

      elem->unpack_indexing(in);
    }

  in += elem->packed_indexing_size();

  // If this is a coarse element,
  // add any element side or edge boundary condition ids
  if (level == 0)
    {
      for (auto s : elem->side_index_range())
        {
          const boundary_id_type num_bcs =
            cast_int<boundary_id_type>(*in++);

          for (boundary_id_type bc_it=0; bc_it < num_bcs; bc_it++)
            mesh->get_boundary_info().add_side
              (elem, s, cast_int<boundary_id_type>(*in++));
        }

      for (auto e : elem->edge_index_range())
        {
          const boundary_id_type num_bcs =
            cast_int<boundary_id_type>(*in++);

          for (boundary_id_type bc_it=0; bc_it < num_bcs; bc_it++)
            mesh->get_boundary_info().add_edge
              (elem, e, cast_int<boundary_id_type>(*in++));
        }

      for (unsigned short sf=0; sf != 2; ++sf)
        {
          const boundary_id_type num_bcs =
            cast_int<boundary_id_type>(*in++);

          for (boundary_id_type bc_it=0; bc_it < num_bcs; bc_it++)
            mesh->get_boundary_info().add_shellface
              (elem, sf, cast_int<boundary_id_type>(*in++));
        }
    }

  // Return the new element
  return elem;
}
//-----------------------------------------------------------------
// Mesh refinement methods
bool MeshRefinement::limit_level_mismatch_at_edge (const unsigned int max_mismatch)
{
  // This function must be run on all processors at once
  parallel_only();

  bool flags_changed = false;


  // Maps holding the maximum element level that touches an edge
  std::map<std::pair<unsigned int, unsigned int>, unsigned char>
    max_level_at_edge;
  std::map<std::pair<unsigned int, unsigned int>, unsigned char>
    max_p_level_at_edge;

  // Loop over all the active elements & fill the maps
  {
    MeshBase::element_iterator       elem_it  = _mesh.active_elements_begin();
    const MeshBase::element_iterator elem_end = _mesh.active_elements_end();

    for (; elem_it != elem_end; ++elem_it)
      {
	const Elem* elem = *elem_it;
	const unsigned char elem_level =
	  elem->level() + ((elem->refinement_flag() == Elem::REFINE) ? 1 : 0);
	const unsigned char elem_p_level =
	  elem->p_level() + ((elem->p_refinement_flag() == Elem::REFINE) ? 1 : 0);

	// Set the max_level at each edge
	for (unsigned int n=0; n<elem->n_edges(); n++)
	  {
            AutoPtr<Elem> edge = elem->build_edge(n);
            unsigned int childnode0 = edge->node(0);
            unsigned int childnode1 = edge->node(1);
            if (childnode1 < childnode0)
              std::swap(childnode0, childnode1);

	    for (const Elem *p = elem; p != NULL; p = p->parent())
	      {
                AutoPtr<Elem> pedge = p->build_edge(n);
		unsigned int node0 = pedge->node(0);
		unsigned int node1 = pedge->node(1);

                if (node1 < node0)
                  std::swap(node0, node1);

		// If elem does not share this edge with its ancestor
		// p, refinement levels of elements sharing p's edge
		// are not restricted by refinement levels of elem.
		// Furthermore, elem will not share this edge with any
		// of p's ancestors, so we can safely break out of the
		// for loop early.
		if (node0 != childnode0 && node1 != childnode1)
		  break;

                childnode0 = node0;
                childnode1 = node1;

                std::pair<unsigned int, unsigned int> edge_key =
                  std::make_pair(node0, node1);

                if (max_level_at_edge.find(edge_key) ==
                    max_level_at_edge.end())
                  {
                    max_level_at_edge[edge_key] = elem_level;
	            max_p_level_at_edge[edge_key] = elem_p_level;
                  }
                else
                  {
	            max_level_at_edge[edge_key] =
	              std::max (max_level_at_edge[edge_key], elem_level);
	            max_p_level_at_edge[edge_key] =
	              std::max (max_p_level_at_edge[edge_key], elem_p_level);
                  }
              }
	  }
      }
  }


  // Now loop over the active elements and flag the elements
  // who violate the requested level mismatch
  {
    MeshBase::element_iterator       elem_it  = _mesh.active_elements_begin();
    const MeshBase::element_iterator elem_end = _mesh.active_elements_end();

    for (; elem_it != elem_end; ++elem_it)
      {
	Elem* elem = *elem_it;
	const unsigned int elem_level = elem->level();
	const unsigned int elem_p_level = elem->p_level();

	// Skip the element if it is already fully flagged
	if (elem->refinement_flag() == Elem::REFINE &&
            elem->p_refinement_flag() == Elem::REFINE)
	  continue;

	// Loop over the nodes, check for possible mismatch
	for (unsigned int n=0; n<elem->n_edges(); n++)
	  {
            AutoPtr<Elem> edge = elem->build_edge(n);
            unsigned int node0 = edge->node(0);
            unsigned int node1 = edge->node(1);
            if (node1 < node0)
              std::swap(node0, node1);

            std::pair<unsigned int, unsigned int> edge_key =
              std::make_pair(node0, node1);

	    // Flag the element for refinement if it violates
	    // the requested level mismatch
	    if ( (elem_level + max_mismatch) < max_level_at_edge[edge_key]
                 && elem->refinement_flag() != Elem::REFINE)
	      {
		elem->set_refinement_flag (Elem::REFINE);
		flags_changed = true;
	      }
	    if ( (elem_p_level + max_mismatch) < max_p_level_at_edge[edge_key]
                 && elem->p_refinement_flag() != Elem::REFINE)
	      {
		elem->set_p_refinement_flag (Elem::REFINE);
		flags_changed = true;
	      }
	  }
      }
  }

  // If flags changed on any processor then they changed globally
  CommWorld.max(flags_changed);

  return flags_changed;
}
示例#28
0
void add_cube_convex_hull_to_mesh(MeshBase& mesh, Point lower_limit, Point upper_limit)
{
#ifdef LIBMESH_HAVE_TETGEN
  SerialMesh cube_mesh(3);

  unsigned n_elem = 1;

  MeshTools::Generation::build_cube(cube_mesh,
				    n_elem,n_elem,n_elem, // n. elements in each direction
				    lower_limit(0), upper_limit(0),
				    lower_limit(1), upper_limit(1),
				    lower_limit(2), upper_limit(2),
				    HEX8);
  
  // The pointset_convexhull() algorithm will ignore the Hex8s
  // in the Mesh, and just construct the triangulation
  // of the convex hull.
  TetGenMeshInterface t(cube_mesh);
  t.pointset_convexhull(); 
  
  // Now add all nodes from the boundary of the cube_mesh to the input mesh.

  // Map from "node id in cube_mesh" -> "node id in mesh".  Initially inserted
  // with a dummy value, later to be assigned a value by the input mesh.
  std::map<unsigned,unsigned> node_id_map;
  typedef std::map<unsigned,unsigned>::iterator iterator;

  {
    MeshBase::element_iterator it = cube_mesh.elements_begin();
    const MeshBase::element_iterator end = cube_mesh.elements_end();
    for ( ; it != end; ++it) 
      {
	Elem* elem = *it;
	  
	for (unsigned s=0; s<elem->n_sides(); ++s)
	  if (elem->neighbor(s) == NULL)
	    {
	      // Add the node IDs of this side to the set
	      AutoPtr<Elem> side = elem->side(s);
		
	      for (unsigned n=0; n<side->n_nodes(); ++n)
		node_id_map.insert( std::make_pair(side->node(n), /*dummy_value=*/0) );
	    }
      }
  }

  // For each node in the map, insert it into the input mesh and keep 
  // track of the ID assigned.
  for (iterator it=node_id_map.begin(); it != node_id_map.end(); ++it)
    {
      // Id of the node in the cube mesh
      unsigned id = (*it).first;

      // Pointer to node in the cube mesh
      Node* old_node = cube_mesh.node_ptr(id);

      // Add geometric point to input mesh
      Node* new_node = mesh.add_point ( *old_node );

      // Track ID value of new_node in map
      (*it).second = new_node->id();
    }
  
  // With the points added and the map data structure in place, we are
  // ready to add each TRI3 element of the cube_mesh to the input Mesh 
  // with proper node assignments
  {
    MeshBase::element_iterator       el     = cube_mesh.elements_begin();
    const MeshBase::element_iterator end_el = cube_mesh.elements_end();
    
    for (; el != end_el; ++el)
      {
	Elem* old_elem = *el;

	if (old_elem->type() == TRI3)
	  {
	    Elem* new_elem = mesh.add_elem(new Tri3);

	    // Assign nodes in new elements.  Since this is an example,
	    // we'll do it in several steps.
	    for (unsigned i=0; i<old_elem->n_nodes(); ++i)
	      {
		// Locate old node ID in the map
		iterator it = node_id_map.find(old_elem->node(i));

		// Check for not found
		if (it == node_id_map.end())
		  {
		    libMesh::err << "Node id " << old_elem->node(i) << " not found in map!" << std::endl;
		    libmesh_error();
		  }

		// Mapping to node ID in input mesh
		unsigned new_node_id = (*it).second;

		// Node pointer assigned from input mesh
		new_elem->set_node(i) = mesh.node_ptr(new_node_id);
	      }
	  }
      }
  }
#endif // LIBMESH_HAVE_TETGEN
}
//-----------------------------------------------------------------
// Mesh refinement methods
bool MeshRefinement::limit_level_mismatch_at_node (const unsigned int max_mismatch)
{
  // This function must be run on all processors at once
  parallel_only();

  bool flags_changed = false;


  // Vector holding the maximum element level that touches a node.
  std::vector<unsigned char> max_level_at_node (_mesh.n_nodes(), 0);
  std::vector<unsigned char> max_p_level_at_node (_mesh.n_nodes(), 0);


  // Loop over all the active elements & fill the vector
  {
    MeshBase::element_iterator       elem_it  = _mesh.active_elements_begin();
    const MeshBase::element_iterator elem_end = _mesh.active_elements_end();

    for (; elem_it != elem_end; ++elem_it)
      {
	const Elem* elem = *elem_it;
	const unsigned char elem_level =
	  elem->level() + ((elem->refinement_flag() == Elem::REFINE) ? 1 : 0);
	const unsigned char elem_p_level =
	  elem->p_level() + ((elem->p_refinement_flag() == Elem::REFINE) ? 1 : 0);

	// Set the max_level at each node
	for (unsigned int n=0; n<elem->n_nodes(); n++)
	  {
	    const unsigned int node_number = elem->node(n);

	    libmesh_assert_less (node_number, max_level_at_node.size());

	    max_level_at_node[node_number] =
	      std::max (max_level_at_node[node_number], elem_level);
	    max_p_level_at_node[node_number] =
	      std::max (max_p_level_at_node[node_number], elem_p_level);
	  }
      }
  }


  // Now loop over the active elements and flag the elements
  // who violate the requested level mismatch
  {
    MeshBase::element_iterator       elem_it  = _mesh.active_elements_begin();
    const MeshBase::element_iterator elem_end = _mesh.active_elements_end();

    for (; elem_it != elem_end; ++elem_it)
      {
	Elem* elem = *elem_it;
	const unsigned int elem_level = elem->level();
	const unsigned int elem_p_level = elem->p_level();

	// Skip the element if it is already fully flagged
	if (elem->refinement_flag() == Elem::REFINE &&
            elem->p_refinement_flag() == Elem::REFINE)
	  continue;

	// Loop over the nodes, check for possible mismatch
	for (unsigned int n=0; n<elem->n_nodes(); n++)
	  {
	    const unsigned int node_number = elem->node(n);

	    // Flag the element for refinement if it violates
	    // the requested level mismatch
	    if ( (elem_level + max_mismatch) < max_level_at_node[node_number]
                 && elem->refinement_flag() != Elem::REFINE)
	      {
		elem->set_refinement_flag (Elem::REFINE);
		flags_changed = true;
	      }
	    if ( (elem_p_level + max_mismatch) < max_p_level_at_node[node_number]
                 && elem->p_refinement_flag() != Elem::REFINE)
	      {
		elem->set_p_refinement_flag (Elem::REFINE);
		flags_changed = true;
	      }
	  }
      }
  }

  // If flags changed on any processor then they changed globally
  CommWorld.max(flags_changed);

  return flags_changed;
}
示例#30
0
文件: vtk_io.C 项目: ZJLi2013/libmesh
void VTKIO::cells_to_vtk()
{
  const MeshBase& mesh = MeshOutput<MeshBase>::mesh();

  vtkSmartPointer<vtkCellArray> cells = vtkSmartPointer<vtkCellArray>::New();
  vtkSmartPointer<vtkIdList> pts = vtkSmartPointer<vtkIdList>::New();

  std::vector<int> types(mesh.n_active_local_elem());
  unsigned active_element_counter = 0;

  vtkSmartPointer<vtkIntArray> elem_id = vtkSmartPointer<vtkIntArray>::New();
  elem_id->SetName("libmesh_elem_id");
  elem_id->SetNumberOfComponents(1);

  vtkSmartPointer<vtkIntArray> subdomain_id = vtkSmartPointer<vtkIntArray>::New();
  subdomain_id->SetName("subdomain_id");
  subdomain_id->SetNumberOfComponents(1);

  MeshBase::const_element_iterator it = mesh.active_local_elements_begin();
  const MeshBase::const_element_iterator end = mesh.active_local_elements_end();
  for (; it != end; ++it, ++active_element_counter)
    {
      Elem *elem = *it;

      pts->SetNumberOfIds(elem->n_nodes());

      // get the connectivity for this element
      std::vector<dof_id_type> conn;
      elem->connectivity(0, VTK, conn);

      for (unsigned int i=0; i<conn.size(); ++i)
        {
          // If the node ID is not found in the _local_node_map, we'll
          // add it to the _vtk_grid.  NOTE[JWP]: none of the examples
          // I have actually enters this section of code...
          if (_local_node_map.find(conn[i]) == _local_node_map.end())
            {
              dof_id_type global_node_id = elem->node(i);

              const Node* the_node = mesh.node_ptr(global_node_id);

              // Error checking...
              if (the_node == NULL)
                {
                  libMesh::err << "Error getting pointer to node "
                               << global_node_id
                               << "!" << std::endl;
                  libmesh_error();
                }

              // InsertNextPoint accepts either a double or float array of length 3.
              Real pt[3] = {0., 0., 0.};
              for (unsigned int d=0; d<LIBMESH_DIM; ++d)
                pt[d] = (*the_node)(d);

              // Insert the point into the _vtk_grid
              vtkIdType local = _vtk_grid->GetPoints()->InsertNextPoint(pt);

              // Update the _local_node_map with the ID returned by VTK
              _local_node_map[global_node_id] = local;
            }

          // Otherwise, the node ID was found in the _local_node_map, so
          // insert it into the vtkIdList.
          pts->InsertId(i, _local_node_map[conn[i]]);
        }

      vtkIdType vtkcellid = cells->InsertNextCell(pts);
      types[active_element_counter] = this->get_elem_type(elem->type());
      elem_id->InsertTuple1(vtkcellid, elem->id());
      subdomain_id->InsertTuple1(vtkcellid, elem->subdomain_id());
    } // end loop over active elements

  _vtk_grid->SetCells(&types[0], cells);
  _vtk_grid->GetCellData()->AddArray(elem_id);
  _vtk_grid->GetCellData()->AddArray(subdomain_id);
}