borderdofexchanger.hh

// -*- tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
// vi: set et ts=8 sw=2 sts=2:
#ifndef DUNE_PDELAB_GRIDOPERATOR_COMMON_BORDERDOFEXCHANGER_HH
#define DUNE_PDELAB_GRIDOPERATOR_COMMON_BORDERDOFEXCHANGER_HH
 
#include <algorithm>
#include <cstddef>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <vector>
 
#include <dune/common/deprecated.hh>
#include <dune/common/parallel/mpihelper.hh>
 
#include <dune/geometry/typeindex.hh>
 
#include <dune/grid/common/datahandleif.hh>
#include <dune/grid/common/gridenums.hh>
 
#include <dune/pdelab/common/borderindexidcache.hh>
#include <dune/pdelab/common/globaldofindex.hh>
#include <dune/pdelab/gridfunctionspace/entityindexcache.hh>
 
namespace Dune {
  namespace PDELab {
 
 
 
 
    template<typename GridOperator>
    class NonOverlappingBorderDOFExchanger
    {
      typedef typename GridOperator::Traits::Jacobian M;
      typedef M Matrix;
      typedef typename GridOperator::Traits GridOperatorTraits;
      typedef typename GridOperatorTraits::JacobianField Scalar;
      typedef typename GridOperatorTraits::TrialGridFunctionSpace GFSU;
      typedef typename GridOperatorTraits::TestGridFunctionSpace GFSV;
      using EntitySet = typename GFSV::Traits::EntitySet;
      static const int dim = EntitySet::dimension;
      using Grid = typename EntitySet::Traits::GridView::Traits::Grid;
      typedef typename Matrix::block_type BlockType;
      typedef typename Grid::Traits::GlobalIdSet IdSet;
      typedef typename IdSet::IdType IdType;
 
      typedef Dune::PDELab::GlobalDOFIndex<
        typename GFSV::Ordering::Traits::DOFIndex::value_type,
        GFSV::Ordering::Traits::DOFIndex::max_depth,
        typename IdSet::IdType
        > GlobalDOFIndex;
 
    public:
      typedef std::unordered_map<
        typename GFSV::Ordering::Traits::DOFIndex,
        std::unordered_set<GlobalDOFIndex>
        > BorderPattern;
 
    private:
      typedef typename GFSV::Ordering::Traits::DOFIndex RowDOFIndex;
      typedef typename GFSU::Ordering::Traits::DOFIndex ColDOFIndex;
 
      typedef std::pair<
        typename RowDOFIndex::TreeIndex,
        typename BorderPattern::mapped_type::value_type
        > PatternMPIData;
 
      typedef std::tuple<
        typename RowDOFIndex::TreeIndex,
        typename BorderPattern::mapped_type::value_type,
        typename M::field_type
        > ValueMPIData;
 
    public:
      NonOverlappingBorderDOFExchanger(const GridOperator& grid_operator)
        : _communication_cache(std::make_shared<CommunicationCache>(grid_operator))
        , _entity_set(grid_operator.testGridFunctionSpace().entitySet())
      {}
 
      void update(const GridOperator& grid_operator)
      {
        _communication_cache = std::make_shared<CommunicationCache>(grid_operator);
      }
 
      class CommunicationCache
        : public BorderIndexIdCache<GFSV>
      {
 
        friend class NonOverlappingBorderDOFExchanger;
        typedef BorderIndexIdCache<GFSV> BaseT;
 
      public:
 
        CommunicationCache(const GridOperator& go)
          : BaseT(go.testGridFunctionSpace())
          , _gfsu(go.trialGridFunctionSpace())
          , _initialized(false)
          , _entity_cache(go.testGridFunctionSpace())
        {}
 
        typedef IdType EntityID;
        typedef typename GFSU::Ordering::Traits::DOFIndex::TreeIndex ColumnTreeIndex;
        typedef std::size_t size_type;
 
        bool initialized() const
        {
          return _initialized;
        }
 
        void finishInitialization()
        {
          _initialized = true;
        }
 
        void update()
        {
          BaseT::update();
          _border_pattern.clear();
          _initialized = false;
        }
 
 
        const BorderPattern& pattern() const
        {
          assert(initialized());
          return _border_pattern;
        }
 
        template<typename LFSVCache, typename LFSUCache, typename LocalPattern>
        void addEntries(const LFSVCache& lfsv_cache, const LFSUCache& lfsu_cache, const LocalPattern& pattern)
        {
          assert(!initialized());
 
          for (typename LocalPattern::const_iterator it = pattern.begin(),
                 end_it = pattern.end();
               it != end_it;
               ++it)
            {
              // skip constrained entries for now. TODO: Is this correct??
              if (lfsv_cache.isConstrained(it->i()) || lfsu_cache.isConstrained(it->j()))
                continue;
 
              const typename LFSVCache::DOFIndex& di = lfsv_cache.dofIndex(it->i());
              const typename LFSUCache::DOFIndex& dj = lfsu_cache.dofIndex(it->j());
 
              size_type row_gt_index = GFSV::Ordering::Traits::DOFIndexAccessor::geometryType(di);
              size_type row_entity_index = GFSV::Ordering::Traits::DOFIndexAccessor::entityIndex(di);
 
              size_type col_gt_index = GFSU::Ordering::Traits::DOFIndexAccessor::geometryType(dj);
              size_type col_entity_index = GFSU::Ordering::Traits::DOFIndexAccessor::entityIndex(dj);
 
              // We are only interested in connections between two border entities.
              if (!this->isBorderEntity(row_gt_index,row_entity_index) ||
                  !this->isBorderEntity(col_gt_index,col_entity_index))
                continue;
 
              _border_pattern[di].insert(GlobalDOFIndex(this->id(col_gt_index,col_entity_index),dj.treeIndex()));
            }
        }
 
 
        template<typename Entity>
        size_type size(const Entity& e) const
        {
          if (!_gfsu.entitySet().contains(e))
            return 0;
          _entity_cache.update(e);
          size_type n = 0;
          for (size_type i = 0; i < _entity_cache.size(); ++i)
            {
              typename BorderPattern::const_iterator it = _border_pattern.find(_entity_cache.dofIndex(i));
              if (!transfer_dof(i,it))
                continue;
              n += it->second.size();
            }
 
          return n;
        }
 
        template<typename Buffer, typename Entity>
        void gather_pattern(Buffer& buf, const Entity& e) const
        {
          if (!_gfsu.entitySet().contains(e))
            return;
          _entity_cache.update(e);
          for (size_type i = 0; i < _entity_cache.size(); ++i)
            {
              typename BorderPattern::const_iterator it = _border_pattern.find(_entity_cache.dofIndex(i));
              if (!transfer_dof(i,it))
                continue;
              for (typename BorderPattern::mapped_type::const_iterator col_it = it->second.begin(),
                     col_end = it->second.end();
                   col_it != col_end;
                   ++col_it)
                buf.write(std::make_pair(_entity_cache.dofIndex(i).treeIndex(),*col_it));
            }
        }
 
        template<typename Buffer, typename Entity>
        void gather_data(Buffer& buf, const Entity& e, const M& matrix) const
        {
          if (!_gfsu.entitySet().contains(e))
            return;
          _entity_cache.update(e);
          for (size_type i = 0; i < _entity_cache.size(); ++i)
            {
              typename BorderPattern::const_iterator it = _border_pattern.find(_entity_cache.dofIndex(i));
              if (!transfer_dof(i,it))
                continue;
              for (typename BorderPattern::mapped_type::const_iterator col_it = it->second.begin(),
                     col_end = it->second.end();
                   col_it != col_end;
                   ++col_it)
                {
                  typename BaseT::EntityIndex col_entity = this->index(col_it->entityID());
 
                  ColDOFIndex dj;
                  GFSU::Ordering::Traits::DOFIndexAccessor::store(dj,col_entity.geometryTypeIndex(),col_entity.entityIndex(),col_it->treeIndex());
                  buf.write(std::make_tuple(_entity_cache.dofIndex(i).treeIndex(),*col_it,matrix(_entity_cache.containerIndex(i),_gfsu.ordering().mapIndex(dj))));
                }
            }
        }
 
      private:
 
        bool transfer_dof(size_type i, typename BorderPattern::const_iterator it) const
        {
          // not a border DOF
          if (it == _border_pattern.end())
            return false;
          else
            return true;
 
          /* Constraints check moved to addEntry()
          // check for constraint
          typename GridOperator::Traits::TrialGridFunctionSpaceConstraints::const_iterator cit = _constraints->find(_entity_cache.containerIndex(i));
 
          // transfer if DOF is not constrained
          // TODO: What about non-Dirichlet constraints??
          return cit == _constraints->end();
          */
        }
 
        const GFSU& _gfsu;
        BorderPattern _border_pattern;
        bool _initialized;
        mutable EntityIndexCache<GFSV,true> _entity_cache;
 
      };
 
      template<typename Pattern>
      class PatternExtender
        : public CommDataHandleIF<PatternExtender<Pattern>, PatternMPIData>
      {
 
        typedef std::size_t size_type;
 
      public:
        typedef PatternMPIData DataType;
 
        bool contains (int dim, int codim) const
        {
          return
            codim > 0 &&
            (_gfsu.dataHandleContains(codim) ||
             _gfsv.dataHandleContains(codim));
        }
 
        bool fixedSize (int dim, int codim) const
        {
          return false;
        }
 
        template<typename Entity>
        size_type size (Entity& e) const
        {
          if (Entity::codimension == 0)
            return 0;
 
          return _communication_cache.size(e);
        }
 
        template<typename MessageBuffer, typename Entity>
        void gather (MessageBuffer& buff, const Entity& e) const
        {
          if (Entity::codimension == 0)
            return;
 
          _communication_cache.gather_pattern(buff,e);
        }
 
        template<typename MessageBuffer, typename Entity>
        void scatter (MessageBuffer& buff, const Entity& e, size_t n)
        {
          if (Entity::codimension == 0)
            return;
 
          for (size_type i = 0; i < n; ++i)
            {
              DataType data;
              buff.read(data);
 
              std::pair<bool,typename CommunicationCache::EntityIndex> col_index = _communication_cache.findIndex(data.second.entityID());
              if (!col_index.first)
                continue;
 
              RowDOFIndex di;
              GFSV::Ordering::Traits::DOFIndexAccessor::store(di,
                                                              e.type(),
                                                              _entity_set.indexSet().index(e),
                                                              data.first);
 
              ColDOFIndex dj;
              GFSU::Ordering::Traits::DOFIndexAccessor::store(dj,
                                                              col_index.second.geometryTypeIndex(),
                                                              col_index.second.entityIndex(),
                                                              data.second.treeIndex());
 
              _pattern.add_link(_gfsv.ordering().mapIndex(di),_gfsu.ordering().mapIndex(dj));
            }
        }
 
        PatternExtender(const NonOverlappingBorderDOFExchanger& dof_exchanger,
                        const GFSU& gfsu,
                        const GFSV& gfsv,
                        Pattern& pattern)
          : _communication_cache(dof_exchanger.communicationCache())
          , _entity_set(dof_exchanger.entitySet())
          , _gfsu(gfsu)
          , _gfsv(gfsv)
          , _pattern(pattern)
        {}
 
      private:
 
        const CommunicationCache& _communication_cache;
        const EntitySet _entity_set;
        const GFSU& _gfsu;
        const GFSV& _gfsv;
        Pattern& _pattern;
 
      };
 
      class EntryAccumulator
        : public CommDataHandleIF<EntryAccumulator,ValueMPIData>
      {
 
        typedef std::size_t size_type;
 
      public:
        typedef ValueMPIData DataType;
 
        bool contains(int dim, int codim) const
        {
          return
            codim > 0 &&
            (_gfsu.dataHandleContains(codim) ||
             _gfsv.dataHandleContains(codim));
        }
 
        bool fixedSize(int dim, int codim) const
        {
          return false;
        }
 
        template<typename Entity>
        size_type size(Entity& e) const
        {
          if (Entity::codimension == 0)
            return 0;
 
          return _communication_cache.size(e);
        }
 
        template<typename MessageBuffer, typename Entity>
        void gather(MessageBuffer& buff, const Entity& e) const
        {
          if (Entity::codimension == 0)
            return;
 
          _communication_cache.gather_data(buff,e,_matrix);
        }
 
        template<typename MessageBuffer, typename Entity>
        void scatter(MessageBuffer& buff, const Entity& e, size_type n)
        {
          if (Entity::codimension == 0)
            return;
 
          for (size_type i = 0; i < n; ++i)
            {
              DataType data;
              buff.read(data);
 
              std::pair<bool,typename CommunicationCache::EntityIndex> col_index = _communication_cache.findIndex(std::get<1>(data).entityID());
              if (!col_index.first)
                continue;
 
              RowDOFIndex di;
              GFSV::Ordering::Traits::DOFIndexAccessor::store(di,
                                                              e.type(),
                                                              _entity_set.indexSet().index(e),
                                                              std::get<0>(data));
 
              ColDOFIndex dj;
              GFSU::Ordering::Traits::DOFIndexAccessor::store(dj,
                                                              col_index.second.geometryTypeIndex(),
                                                              col_index.second.entityIndex(),
                                                              std::get<1>(data).treeIndex());
 
              _matrix(_gfsv.ordering().mapIndex(di),_gfsu.ordering().mapIndex(dj)) += std::get<2>(data);
            }
        }
 
 
        EntryAccumulator(const NonOverlappingBorderDOFExchanger& dof_exchanger,
                         const GFSU& gfsu,
                         const GFSV& gfsv,
                         Matrix& matrix)
          : _communication_cache(dof_exchanger.communicationCache())
          , _entity_set(dof_exchanger.entitySet())
          , _gfsu(gfsu)
          , _gfsv(gfsv)
          , _matrix(matrix)
        {}
 
      private:
 
        const CommunicationCache& _communication_cache;
        EntitySet _entity_set;
        const GFSU& _gfsu;
        const GFSV& _gfsv;
        Matrix& _matrix;
 
      };
 
      void accumulateBorderEntries(const GridOperator& grid_operator, Matrix& matrix)
      {
        if (_entity_set.gridView().comm().size() > 1)
          {
            EntryAccumulator data_handle(*this,
                                         grid_operator.testGridFunctionSpace(),
                                         grid_operator.trialGridFunctionSpace(),
                                         matrix);
            _entity_set.gridView().communicate(data_handle,
                                               InteriorBorder_InteriorBorder_Interface,
                                               ForwardCommunication);
          }
      }
 
      CommunicationCache& communicationCache()
      {
        return *_communication_cache;
      }
 
      const CommunicationCache& communicationCache() const
      {
        return *_communication_cache;
      }
 
      std::shared_ptr<CommunicationCache> communicationCacheStorage()
      {
        return _communication_cache;
      }
 
      const EntitySet& entitySet() const
      {
        return _entity_set;
      }
 
    private:
 
      std::shared_ptr<CommunicationCache> _communication_cache;
      EntitySet _entity_set;
 
    };
 
 
    template<typename GridOperator>
    class NoDataBorderDOFExchanger
    {
 
    public:
 
      typedef NoDataBorderDOFExchanger CommunicationCache;
 
      typedef Empty BorderPattern;
 
      NoDataBorderDOFExchanger()
      {}
 
      NoDataBorderDOFExchanger(const GridOperator& grid_operator)
      {}
 
      void accumulateBorderEntries(const GridOperator& grid_operator, typename GridOperator::Traits::Jacobian& matrix)
      {}
 
      CommunicationCache& communicationCache()
      {
        return *this;
      }
 
      const CommunicationCache& communicationCache() const
      {
        return *this;
      }
 
      void update(const GridOperator& grid_operator)
      {}
 
    };
 
 
    template<typename GridOperator>
    class OverlappingBorderDOFExchanger :
      public NoDataBorderDOFExchanger<GridOperator>
    {
 
    public:
 
      OverlappingBorderDOFExchanger()
      {}
 
      OverlappingBorderDOFExchanger(const GridOperator& grid_operator)
      {}
 
    };
 
 
  } // namespace PDELab
} // namespace Dune
 
#endif // DUNE_PDELAB_GRIDOPERATOR_COMMON_BORDERDOFEXCHANGER_HH