//
// Software License for AMDiS
//
// Copyright (c) 2010 Dresden University of Technology 
// All rights reserved.
// Authors: Simon Vey, Thomas Witkowski et al.
//
// This file is part of AMDiS
//
// See also license.opensource.txt in the distribution.


#include "ParallelDebug.h"
#include "MeshDistributor.h"
#include "ProblemVec.h"
#include "DOFVector.h"
#include "FixVec.h"
#include "StdMpi.h"
#include "Debug.h"
#include "MpiHelper.h"

namespace AMDiS {

  void ParallelDebug::testInteriorBoundary(MeshDistributor &pdb)
  {
    FUNCNAME("ParallelDebug::testInteriorBoundary()");

    typedef MeshDistributor::RankToBoundMap RankToBoundMap;

    std::vector<int*> sendBuffers, recvBuffers;

    MPI::Request request[pdb.myIntBoundary.boundary.size() + 
			 pdb.otherIntBoundary.boundary.size() +
                         pdb.periodicBoundary.boundary.size() * 2];
    int requestCounter = 0;


    // === Send rank's boundary information. ===

    for (RankToBoundMap::iterator rankIt = pdb.myIntBoundary.boundary.begin();
	 rankIt != pdb.myIntBoundary.boundary.end(); ++rankIt) {

      int nSendInt = rankIt->second.size();
      int* buffer = new int[nSendInt];
      for (int i = 0; i < nSendInt; i++)
	buffer[i] = (rankIt->second)[i].rankObj.elIndex;
      
      sendBuffers.push_back(buffer);
      
      request[requestCounter++] =
	pdb.mpiComm.Isend(buffer, nSendInt, MPI_INT, rankIt->first, 0);
    }


    // === Receive information from other ranks about the interior boundaries. ====

    for (RankToBoundMap::iterator rankIt = pdb.otherIntBoundary.boundary.begin();
	 rankIt != pdb.otherIntBoundary.boundary.end(); ++rankIt) {
      int nRecvInt = rankIt->second.size();
      int *buffer = new int[nRecvInt];
      recvBuffers.push_back(buffer);

      request[requestCounter++] = 
	pdb.mpiComm.Irecv(buffer, nRecvInt, MPI_INT, rankIt->first, 0);
    }


    // === To the last, do the same of periodic boundaries. ===

    for (RankToBoundMap::iterator rankIt = pdb.periodicBoundary.boundary.begin();
	 rankIt != pdb.periodicBoundary.boundary.end(); ++rankIt) {
      int nValues = rankIt->second.size();
      int* sBuffer = new int[nValues];
      for (int i = 0; i < nValues; i++)
	sBuffer[i] = (rankIt->second)[i].rankObj.elIndex;

      sendBuffers.push_back(sBuffer);

      request[requestCounter++] =
	pdb.mpiComm.Isend(sBuffer, nValues, MPI_INT, rankIt->first, 0);

      int *rBuffer = new int[nValues];
      recvBuffers.push_back(rBuffer);

      request[requestCounter++] = 
	pdb.mpiComm.Irecv(rBuffer, nValues, MPI_INT, rankIt->first, 0);      
    }

    // === Finish communication and delete all send buffers. ===

    MPI::Request::Waitall(requestCounter, request);
    for (int i = 0; i < static_cast<int>(sendBuffers.size()); i++)
      delete [] sendBuffers[i];


    // === Finally, check the results, i.e., the indices of element at the     === 
    // === boundaries, if they fit together. First check the interior bounds,  ===
    // === and after this the periodic ones.                                   ===

    int bufCounter = 0;
    for (RankToBoundMap::iterator rankIt = pdb.otherIntBoundary.boundary.begin();
	 rankIt != pdb.otherIntBoundary.boundary.end(); ++rankIt) {

      TEST_EXIT(rankIt->second.size() == 
		pdb.otherIntBoundary.boundary[rankIt->first].size())
	("Boundaries does not fit together!\n");      

      for (unsigned int i = 0; i < rankIt->second.size(); i++) {
	int elIndex1 = recvBuffers[bufCounter][i];
	int elIndex2 = pdb.otherIntBoundary.boundary[rankIt->first][i].neighObj.elIndex;

	TEST_EXIT(elIndex1 == elIndex2)("Wrong element index at interior boundary!\n");
      }

      delete [] recvBuffers[bufCounter++];
    }


    for (RankToBoundMap::iterator rankIt = pdb.periodicBoundary.boundary.begin();
	 rankIt != pdb.periodicBoundary.boundary.end(); ++rankIt) {
      for (unsigned int i = 0; i < rankIt->second.size(); i++) {
	int elIndex1 = recvBuffers[bufCounter][i];
	int elIndex2 = pdb.periodicBoundary.boundary[rankIt->first][i].neighObj.elIndex;

	TEST_EXIT(elIndex1 == elIndex2)("Wrong element index at periodic boundary!\n");
      }

      delete [] recvBuffers[bufCounter++];
    }
  }


  void ParallelDebug::testCommonDofs(MeshDistributor &pdb, bool printCoords)
  {
    FUNCNAME("ParallelDebug::testCommonDofs()");

    clock_t first = clock();

    int testCommonDofs = 1;
    GET_PARAMETER(0, "dbg->test common dofs", "%d", &testCommonDofs);
    if (testCommonDofs == 0) {
      MSG("Skip test common dofs!\n");
      return;
    }

    /// Defines a mapping type from rank numbers to sets of coordinates.
    typedef std::map<int, std::vector<WorldVector<double> > > RankToCoords;

    /// Defines a mapping type from rank numbers to sets of DOFs.
    typedef std::map<int, DofContainer> RankToDofContainer;

    // Maps to each neighbour rank an array of WorldVectors. This array contains the 
    // coordinates of all DOFs this rank shares on the interior boundary with the 
    // neighbour rank. A rank sends the coordinates to another rank, if it owns the
    // boundarys DOFs.
    RankToCoords sendCoords;

    // A rank receives all boundary DOFs that are at its interior boundaries but are
    // not owned by the rank. This map stores for each rank the coordinates of DOFs
    // this rank expectes to receive from.
    RankToCoords recvCoords;

    DOFVector<WorldVector<double> > coords(pdb.feSpace, "dofCorrds");
    pdb.mesh->getDofIndexCoords(pdb.feSpace, coords);

    for (RankToDofContainer::iterator it = pdb.sendDofs.begin();
	 it != pdb.sendDofs.end(); ++it)
      for (DofContainer::iterator dofIt = it->second.begin(); 
	   dofIt != it->second.end(); ++dofIt)
	sendCoords[it->first].push_back(coords[**dofIt]);

    for (RankToDofContainer::iterator it = pdb.recvDofs.begin();
	 it != pdb.recvDofs.end(); ++it)
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt)
	recvCoords[it->first].push_back(coords[**dofIt]);

    std::vector<int> sendSize(pdb.mpiSize, 0);
    std::vector<int> recvSize(pdb.mpiSize, 0);
    std::vector<int> recvSizeBuffer(pdb.mpiSize, 0);
    MPI::Request request[(pdb.mpiSize - 1) * 2];
    int requestCounter = 0;

    for (RankToCoords::iterator it = sendCoords.begin(); it != sendCoords.end(); ++it)
      sendSize[it->first] = it->second.size();

    for (RankToCoords::iterator it = recvCoords.begin(); it != recvCoords.end(); ++it)
      recvSize[it->first] = it->second.size();

    for (int i = 0; i < pdb.mpiSize; i++) {
      if (i == pdb.mpiRank)
	continue;

      request[requestCounter++] = 
	pdb.mpiComm.Isend(&(sendSize[i]), 1, MPI_INT, i, 0);
    }   

    for (int i = 0; i < pdb.mpiSize; i++) {
      if (i == pdb.mpiRank)
	continue;

      request[requestCounter++] = 
	pdb.mpiComm.Irecv(&(recvSizeBuffer[i]), 1, MPI_INT, i, 0);
    }

    MPI::Request::Waitall(requestCounter, request);


    int foundError = 0;
    for (int i = 0; i < pdb.mpiSize; i++) {
      if (i == pdb.mpiRank)
	continue;

      if (recvSize[i] != recvSizeBuffer[i]) {
	ERROR("MPI rank %d expectes to receive %d DOFs from rank %d. But this rank sends %d DOFs!\n", 
	      pdb.mpiRank, recvSize[i], i, recvSizeBuffer[i]);	
	foundError = 1;
      }
    }
    mpi::globalAdd(foundError);
    TEST_EXIT(foundError == 0)("Error found on at least on rank!\n");

    // === Now we know that the number of send and received DOFs fits together. ===
    // === So we can check if also the coordinates of the communicated DOFs are ===
    // === the same on both corresponding ranks.                                ===

    typedef std::vector<WorldVector<double> > CoordsVec;
    StdMpi<CoordsVec> stdMpi(pdb.mpiComm, true);
    stdMpi.send(sendCoords);
    stdMpi.recv(recvCoords);   
    stdMpi.startCommunication<double>(MPI_DOUBLE);

    int dimOfWorld = Global::getGeo(WORLD);

    // === Compare the received with the expected coordinates. ===

    for (RankToCoords::iterator it = stdMpi.getRecvData().begin(); 
	 it != stdMpi.getRecvData().end(); ++it) {
      for (unsigned int i = 0; i < it->second.size(); i++) {
	WorldVector<double> tmp = (it->second)[i];
	tmp -=  recvCoords[it->first][i];

	if (norm(tmp) > 1e-13) {
	  // === Print error message if the coordinates are not the same. ===
	  if (printCoords) {
	    MSG("[DBG] i = %d\n", i);	  
	    std::stringstream oss;
	    oss.precision(5);
	    oss << "[DBG] Rank " << pdb.mpiRank << " from rank " << it->first
		<< " expect coords (";
	    for (int k = 0; k < dimOfWorld; k++) {
	      oss << recvCoords[it->first][i][k];
	      if (k + 1 < dimOfWorld)
		oss << " / ";
	    }
	    oss << ")  received coords (";
	    for (int k = 0; k < dimOfWorld; k++) {
	      oss << (it->second)[i][k];
	      if (k + 1 < dimOfWorld)
		oss << " / ";
	    }
	    oss << ")";
	    MSG("%s\n", oss.str().c_str());
	    
	    debug::printInfoByDof(pdb.feSpace, *(pdb.recvDofs[it->first][i]));
	  }
	  ERROR("Wrong DOFs in rank %d!\n", pdb.mpiRank);
	  foundError = 1;
	}	 
      }
    }
    mpi::globalAdd(foundError);
    TEST_EXIT(foundError == 0)("Error found on at least on rank!\n");

    INFO(pdb.info, 8)("Test common dofs needed %.5f seconds\n", TIME_USED(first, clock()));
  }


  void ParallelDebug::testGlobalIndexByCoords(MeshDistributor &pdb)
  {
    FUNCNAME("ParallelDebug::testGlobalIndexByCoords()");

    DOFVector<WorldVector<double> > coords(pdb.feSpace, "tmp");
    pdb.mesh->getDofIndexCoords(pdb.feSpace, coords);

    typedef std::map<WorldVector<double>, int> CoordsIndexMap;
    CoordsIndexMap coordsToIndex;

    DOFIterator<WorldVector<double> > it(&coords, USED_DOFS);
    for (it.reset(); !it.end(); ++it)
      coordsToIndex[(*it)] = pdb.mapLocalGlobalDofs[it.getDOFIndex()];    

    StdMpi<CoordsIndexMap> stdMpi(pdb.mpiComm, true);
    for (RankToDofContainer::iterator it = pdb.sendDofs.begin();
	 it != pdb.sendDofs.end(); ++it)
      stdMpi.send(it->first, coordsToIndex);
    for (RankToDofContainer::iterator it = pdb.recvDofs.begin();
	 it != pdb.recvDofs.end(); ++it)
      stdMpi.recv(it->first);
   
    stdMpi.startCommunication<double>(MPI_DOUBLE); 

    int foundError = 0;
    for (RankToDofContainer::iterator it = pdb.recvDofs.begin();
	 it != pdb.recvDofs.end(); ++it) {
      CoordsIndexMap& otherCoords = stdMpi.getRecvData(it->first);

      for (CoordsIndexMap::iterator coordsIt = otherCoords.begin();
	   coordsIt != otherCoords.end(); ++coordsIt) {
	if (coordsToIndex.count(coordsIt->first) == 1 &&
	    coordsToIndex[coordsIt->first] != coordsIt->second) {
	  std::stringstream oss;
	  oss.precision(5);
	  oss << "DOF at coords ";
	  for (int i = 0; i < Global::getGeo(WORLD); i++)
	    oss << coordsIt->first[i] << " ";
	  oss << " do not fit together on rank " 
	      << pdb.getMpiRank() << " (global index: " 
	      << coordsToIndex[coordsIt->first] << " and on rank "
	      << it->first << " (global index: " << coordsIt->second << ")";

	  MSG("[DBG] %s\n", oss.str().c_str());
	  foundError = 1;
	}
      }
    }

    mpi::globalAdd(foundError);
    TEST_EXIT(foundError == 0)("Error found on at least on rank!\n");
  }


  void ParallelDebug::testAllElements(MeshDistributor &pdb)
  {
    FUNCNAME("ParallelDebug::testAllElements()");

    std::set<int> macroElements;
    int minElementIndex = std::numeric_limits<int>::max();
    int maxElementIndex = std::numeric_limits<int>::min();   

    TraverseStack stack;
    ElInfo *elInfo = stack.traverseFirst(pdb.mesh, 0, Mesh::CALL_EL_LEVEL);
    while (elInfo) {
      int elIndex = elInfo->getElement()->getIndex();
      minElementIndex = std::min(minElementIndex, elIndex);
      maxElementIndex = std::max(maxElementIndex, elIndex);
      macroElements.insert(elInfo->getElement()->getIndex());
      elInfo = stack.traverseNext(elInfo);      
    }
    
    int globalMinIndex, globalMaxIndex;
    pdb.mpiComm.Allreduce(&minElementIndex, &globalMinIndex, 1, MPI_INT, MPI_MIN);
    pdb.mpiComm.Allreduce(&maxElementIndex, &globalMaxIndex, 1, MPI_INT, MPI_MAX);

    TEST_EXIT(globalMinIndex == 0)("No macro element with index 0!\n");
    for (int i = 0; i <= globalMaxIndex; i++) {
      int sendId = macroElements.count(i);
      int recvId = 0;
      pdb.mpiComm.Allreduce(&sendId, &recvId, 1, MPI_INT, MPI_SUM);

      if (recvId != 1 && pdb.mpiRank == 0) {
	if (recvId == 0) {
	  ERROR_EXIT("Element %d has no member partition!\n", i);
	}

	if (recvId > 1) {
	  ERROR_EXIT("Element %d is member of more than pne partition!\n", i);
	}
      }
    }
  }


  void ParallelDebug::testDofContainerCommunication(MeshDistributor &pdb, 
						    RankToDofContainer &sendDofs,
						    RankToDofContainer &recvDofs)
  {
    FUNCNAME("ParallelDebug::testDofContainerCommunication()");

    std::map<int, int> sendNumber;
    for (RankToDofContainer::iterator it = sendDofs.begin(); it != sendDofs.end(); ++it)
      sendNumber[it->first] = it->second.size();
    
    StdMpi<int> stdMpi(pdb.mpiComm);
    stdMpi.send(sendNumber);
    for (RankToDofContainer::iterator it = recvDofs.begin(); it != recvDofs.end(); ++it)    
      stdMpi.recv(it->first);
    stdMpi.startCommunication<int>(MPI_INT);    
     
    int foundError = 0;
    for (std::map<int, int>::iterator it = stdMpi.getRecvData().begin();
	 it != stdMpi.getRecvData().end(); ++it) {
      if (it->second != static_cast<int>(recvDofs[it->first].size())) {
	ERROR("Rank expectes %d DOFs to receive from rank %d, but %d DOFs are received!\n", 
	      recvDofs[it->first].size(), it->first, it->second);
	foundError = 1;
      }
    }

    mpi::globalAdd(foundError);
    TEST_EXIT(foundError == 0)("Error found on at least one rank!\n");
  }


  void ParallelDebug::testDoubleDofs(Mesh *mesh)
  {
    FUNCNAME("ParallelDebug::testDoubleDofs()");

    std::map<WorldVector<double>, DegreeOfFreedom> cMap;
    int foundError = 0;

    TraverseStack stack;
    ElInfo *elInfo = stack.traverseFirst(mesh, -1, Mesh::CALL_LEAF_EL | Mesh::FILL_COORDS);
    while (elInfo) {
      for (int i = 0; i < 3; i++) {
	WorldVector<double> &c = elInfo->getCoord(i);
	if (cMap.count(c) == 0) {
	  cMap[c] = elInfo->getElement()->getDof(i, 0);
	} else {
	  if (cMap[c] != elInfo->getElement()->getDof(i, 0)) {
	    MSG("[DBG] Found two DOFs %d and %d with the same coords %f %f!\n",
		cMap[c], elInfo->getElement()->getDof(i, 0), c[0], c[1]);
	    foundError = 1;
	  }
	}
      }
      
      elInfo = stack.traverseNext(elInfo);
    }
    
    mpi::globalAdd(foundError);
    TEST_EXIT(foundError == 0)("Error found on at least one rank!\n");
  }


  void ParallelDebug::printMapLocalGlobal(MeshDistributor &pdb, int rank)
  {    
    if (rank == -1 || pdb.mpiRank == rank) {
      std::cout << "====== DOF MAP LOCAL -> GLOBAL ====== " << std::endl;
      
      typedef std::map<DegreeOfFreedom, DegreeOfFreedom> DofMapping;
      typedef std::map<int, DofContainer> RankToDofContainer;

      for (DofMapping::iterator it = pdb.mapLocalGlobalDofs.begin();
	   it != pdb.mapLocalGlobalDofs.end(); it++) {
	DegreeOfFreedom localdof = -1;
	if (pdb.mapLocalDofIndex.count(it->first) > 0)
	  localdof = pdb.mapLocalDofIndex[it->first];
	
	std::cout << "DOF " << it->first << " " 
		  << it->second << " " 
		  << localdof << std::endl;
	WorldVector<double> coords;
	pdb.mesh->getDofIndexCoords(it->first, pdb.feSpace, coords);
	coords.print();

	for (RankToDofContainer::iterator rankit = pdb.sendDofs.begin();
	     rankit != pdb.sendDofs.end(); ++rankit) {
	  for (DofContainer::iterator dofit = rankit->second.begin();
	       dofit != rankit->second.end(); ++dofit)
	    if (**dofit == it->first)
	      std::cout << "SEND DOF TO " << rankit->first << std::endl;	  
	}

	for (RankToDofContainer::iterator rankit = pdb.recvDofs.begin();
	     rankit != pdb.recvDofs.end(); ++rankit) {
	  for (DofContainer::iterator dofit = rankit->second.begin();
	       dofit != rankit->second.end(); ++dofit)
	    if (**dofit == it->first)
	      std::cout << "RECV DOF FROM " << rankit->first << std::endl;	  
	}

	std::cout << "------" << std::endl;
      }
    }
  }


  void ParallelDebug::printMapPeriodic(MeshDistributor &pdb, int rank)
  {
    FUNCNAME("ParallelDebug::printMapPeriodic()");

    ERROR_EXIT("Function must be rewritten!\n");

#if 0
    typedef std::map<DegreeOfFreedom, DegreeOfFreedom> DofMapping;
    typedef std::map<DegreeOfFreedom, std::set<DegreeOfFreedom> > PeriodicDofMap;

    if (rank == -1 || pdb.mpiRank == rank) {
      std::cout << "====== DOF MAP PERIODIC ====== " << std::endl;

      for (PeriodicDofMap::iterator it = pdb.periodicDof.begin();
	   it != pdb.periodicDof.end(); ++it) {
	std::cout << "DOF MAP " << it->first << ": ";
	for (std::set<DegreeOfFreedom>::iterator dofit = it->second.begin();
	     dofit != it->second.end(); ++dofit)
	  std::cout << *dofit << " ";
	std::cout << std::endl;

	DegreeOfFreedom localdof = -1;
	for (DofMapping::iterator dofIt = pdb.mapLocalGlobalDofs.begin();
	     dofIt != pdb.mapLocalGlobalDofs.end(); ++dofIt)
	  if (dofIt->second == it->first)
	    localdof = dofIt->first;

	TEST_EXIT(localdof != -1)("There is something wrong!\n");

	WorldVector<double> coords;
	pdb.mesh->getDofIndexCoords(localdof, pdb.feSpace, coords);
	coords.print();
      }
    }
#endif
  }

  
  void ParallelDebug::printRankDofs(MeshDistributor &pdb, 
				    int rank, 
				    DofContainer& rankDofs,
				    DofContainer& rankAllDofs)
  {
    if (rank == -1 || pdb.mpiRank == rank) {
      std::cout << "====== RANK DOF INFORMATION ====== " << std::endl;

      std::cout << "  RANK OWNED DOFS: " << std::endl;
      for (DofContainer::iterator dofit = rankDofs.begin();
	   dofit != rankDofs.end(); ++dofit) {
	std::cout << "    " << **dofit << std::endl;
	WorldVector<double> coords;
	pdb.mesh->getDofIndexCoords(*dofit, pdb.feSpace, coords);
	coords.print();
      }

      std::cout << "  RANK ALL DOFS: " << std::endl;
      for (DofContainer::iterator dofit = rankAllDofs.begin();
	   dofit != rankAllDofs.end(); ++dofit) {
	std::cout << "    " << **dofit << std::endl;
	WorldVector<double> coords;
	pdb.mesh->getDofIndexCoords(*dofit, pdb.feSpace, coords);
	coords.print();
      }      
    }
  }


  void ParallelDebug::printBoundaryInfo(MeshDistributor &pdb)
  {
    FUNCNAME("ParallelDebug::printBoundaryInfo()");

    for (InteriorBoundary::iterator it(pdb.myIntBoundary); !it.end(); ++it) {
      MSG("Rank owned boundary with rank %d: \n", it.getRank());
      MSG("  ranks obj-ind: %d  sub-obj: %d   ith-obj: %d\n",
	  it->rankObj.elIndex, it->rankObj.subObj, it->rankObj.ithObj);
      MSG("  neigh obj-ind: %d  sub-obj: %d   ith-obj: %d\n",
	  it->neighObj.elIndex, it->neighObj.subObj, it->neighObj.ithObj);
    }

    for (InteriorBoundary::iterator it(pdb.otherIntBoundary); !it.end(); ++it) {
      MSG("Other owned boundary with rank %d: \n", it.getRank());
      MSG("  ranks obj-ind: %d  sub-obj: %d   ith-obj: %d\n",
	  it->rankObj.elIndex, it->rankObj.subObj, it->rankObj.ithObj);
      MSG("  neigh obj-ind: %d  sub-obj: %d   ith-obj: %d\n",
	  it->neighObj.elIndex, it->neighObj.subObj, it->neighObj.ithObj);
    }

    for (InteriorBoundary::iterator it(pdb.periodicBoundary); !it.end(); ++it) {
      MSG("Periodic boundary with rank %d: \n", it.getRank());
      MSG("  ranks obj-ind: %d  sub-obj: %d   ith-obj: %d\n",
	  it->rankObj.elIndex, it->rankObj.subObj, it->rankObj.ithObj);
      MSG("  neigh obj-ind: %d  sub-obj: %d   ith-obj: %d\n",
	  it->neighObj.elIndex, it->neighObj.subObj, it->neighObj.ithObj);
    }    
  }


  void ParallelDebug::writeDebugFile(MeshDistributor &pdb,
				     std::string prefix, std::string postfix)
  {
    FUNCNAME("ParallelDebug::writeCoordsFile()");

    std::stringstream filename;
    filename << prefix << "-" << pdb.mpiRank << "." << postfix;

    DOFVector<WorldVector<double> > coords(pdb.feSpace, "tmp");
    pdb.mesh->getDofIndexCoords(pdb.feSpace, coords);

    typedef std::map<int, std::vector<DegreeOfFreedom> > ElDofMap;
    ElDofMap elDofMap;
    TraverseStack stack;
    const BasisFunction *basisFcts = pdb.feSpace->getBasisFcts();
    std::vector<DegreeOfFreedom> localIndices(basisFcts->getNumber());
    ElInfo *elInfo = stack.traverseFirst(pdb.mesh, -1, Mesh::CALL_LEAF_EL);
    while (elInfo) {
      basisFcts->getLocalIndices(elInfo->getElement(), 
				 pdb.feSpace->getAdmin(), localIndices);
      elDofMap[elInfo->getElement()->getIndex()] = localIndices;
      elInfo = stack.traverseNext(elInfo);
    }

    // === Write informations about all DOFs. ===

    std::ofstream file;
    file.open(filename.str().c_str());
    file << coords.getUsedSize() << "\n";
    DOFIterator<WorldVector<double> > it(&coords, USED_DOFS);
    for (it.reset(); !it.end(); ++it) {
      file << it.getDOFIndex() << " " 
	   << pdb.mapLocalGlobalDofs[it.getDOFIndex()] << " "
	   << pdb.getIsRankDof(it.getDOFIndex());
      for (int i = 0; i < pdb.mesh->getDim(); i++)
	file << " " << (*it)[i];
      file << "\n";
    }

    // === Write to all elements in ranks mesh the included dofs. ===

    file << elDofMap.size() << "\n";
    file << basisFcts->getNumber() << "\n";
    for (ElDofMap::iterator it = elDofMap.begin(); it != elDofMap.end(); ++it) {
      file << it->first << "\n";
      for (int i = 0; i < basisFcts->getNumber(); i++) 
	file << it->second[i] << " ";
      file << "\n";
    }

    file.close();
  }

}