PetscSolverFeti.cc 33.5 KB
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//
// 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 "parallel/PetscSolverFeti.h"
#include "parallel/StdMpi.h"
#include "parallel/MpiHelper.h"

namespace AMDiS {

  using namespace std;


#ifdef HAVE_PETSC_DEV 
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  // y = mat * x
  int petscMultMatSchurPrimal(Mat mat, Vec x, Vec y)
  {
    // S_PiPi = K_PiPi - K_PiB inv(K_BB) K_BPi

    void *ctx;
    MatShellGetContext(mat, &ctx);
    PetscSchurPrimalData* data = static_cast<PetscSchurPrimalData*>(ctx);

    MatMult(*(data->mat_b_primal), x, data->tmp_vec_b);
    KSPSolve(*(data->ksp_b), data->tmp_vec_b, data->tmp_vec_b);

    MatMult(*(data->mat_primal_b), data->tmp_vec_b, data->tmp_vec_primal);
    MatMult(*(data->mat_primal_primal), x, y);
    VecAXPBY(y, -1.0, 1.0, data->tmp_vec_primal);

    return 0;
  }


  // y = mat * x
  int petscMultMatFeti(Mat mat, Vec x, Vec y)
  {
    // F = L inv(K_BB) trans(L) + L inv(K_BB) K_BPi inv(S_PiPi) K_PiB inv(K_BB) trans(L)

    void *ctx;
    MatShellGetContext(mat, &ctx);
    PetscFetiData* data = static_cast<PetscFetiData*>(ctx);

    // y = L inv(K_BB) trans(L) x
    MatMultTranspose(*(data->mat_lagrange), x, data->tmp_vec_b);
    KSPSolve(*(data->ksp_b), data->tmp_vec_b, data->tmp_vec_b);
    MatMult(*(data->mat_lagrange), data->tmp_vec_b, y);

    // tmp_vec_primal = inv(S_PiPi) K_PiB inv(K_BB) trans(L)
    MatMult(*(data->mat_primal_b), data->tmp_vec_b, data->tmp_vec_primal);
    KSPSolve(*(data->ksp_schur_primal), data->tmp_vec_primal, data->tmp_vec_primal);

    // tmp_vec_lagrange = L inv(K_BB) K_BPi tmp_vec_primal
    //                  = L inv(K_BB) K_BPi inv(S_PiPi) K_PiB inv(K_BB) trans(L)
    MatMult(*(data->mat_b_primal), data->tmp_vec_primal, data->tmp_vec_b);
    KSPSolve(*(data->ksp_b), data->tmp_vec_b, data->tmp_vec_b);
    MatMult(*(data->mat_lagrange), data->tmp_vec_b, data->tmp_vec_lagrange);

    VecAXPBY(y, 1.0, 1.0, data->tmp_vec_lagrange);

    return 0;
  }


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  void PetscSolverFeti::updateDofData()
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  {
    FUNCNAME("PetscSolverFeti::updateDofData()");
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    TEST_EXIT(meshDistributor->getMesh()->getDim() == 2)
      ("Works for 2D problems only!");

    TEST_EXIT(meshDistributor->getFeSpace()->getBasisFcts()->getDegree() == 1)
      ("Works for linear basis functions only!\n");
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    createPrimals();

    createDuals();

    createLagrange();

    createIndexB();
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  }


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  void PetscSolverFeti::createPrimals()
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  {
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    FUNCNAME("PetscSolverFeti::createPrimals()");  
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    // === Define all vertices on the interior boundaries of the macro mesh ===
    // === to be primal variables.                                          ===

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    primals.clear();
    DofContainerSet& vertices = 
      meshDistributor->getBoundaryDofInfo().geoDofs[VERTEX];
    TEST_EXIT_DBG(vertices.size())("No primal vertices on this rank!\n");
    for (DofContainerSet::iterator it = vertices.begin(); 
	 it != vertices.end(); ++it)
      primals.insert(**it);
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    // === Calculate the number of primals that are owned by the rank and ===
    // === create local indices of the primals starting at zero.          ===

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    globalPrimalIndex.clear();
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    nRankPrimals = 0;
    for (DofIndexSet::iterator it = primals.begin(); it != primals.end(); ++it)
      if (meshDistributor->getIsRankDof(*it)) {
	globalPrimalIndex[*it] = nRankPrimals;
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	nRankPrimals++;
      }

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    // === Get overall number of primals and rank's displacement in the ===
    // === numbering of the primals.                                    ===

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    nOverallPrimals = 0;
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    rStartPrimals = 0;
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    mpi::getDofNumbering(meshDistributor->getMpiComm(),
			 nRankPrimals, rStartPrimals, nOverallPrimals);

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    // === Create global primal index for all primals. ===

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    for (DofMapping::iterator it = globalPrimalIndex.begin();
	 it != globalPrimalIndex.end(); ++it)
      it->second += rStartPrimals;

    MSG_DBG("nRankPrimals = %d   nOverallPrimals = %d\n",
	    nRankPrimals, nOverallPrimals);
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    // === Communicate primal's global index from ranks that own the     ===
    // === primals to ranks that contain this primals but are not owning ===
    // === them.                                                         ===

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    StdMpi<vector<int> > stdMpi(meshDistributor->getMpiComm());
    RankToDofContainer& sendDofs = meshDistributor->getSendDofs();
    for (RankToDofContainer::iterator it = sendDofs.begin();
	 it != sendDofs.end(); ++it)
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt)
	if (globalPrimalIndex.count(**dofIt))
	  stdMpi.getSendData(it->first).push_back(globalPrimalIndex[**dofIt]);
    stdMpi.updateSendDataSize();

    RankToDofContainer& recvDofs = meshDistributor->getRecvDofs();
    for (RankToDofContainer::iterator it = recvDofs.begin();
	 it != recvDofs.end(); ++it) {
      bool recvFromRank = false;
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt)
	if (primals.count(**dofIt) && 
	    meshDistributor->getIsRankDof(**dofIt) == false) {
	  recvFromRank = true;
	  break;
	}

      if (recvFromRank) 
	stdMpi.recv(it->first);
    }
    stdMpi.startCommunication();

    for (RankToDofContainer::iterator it = recvDofs.begin();
	 it != recvDofs.end(); ++it) {
      int i = 0;
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt) {
	if (primals.count(**dofIt) && 
	    meshDistributor->getIsRankDof(**dofIt) == false)
	  globalPrimalIndex[**dofIt] = stdMpi.getRecvData(it->first)[i++];
      }
    }

    TEST_EXIT_DBG(primals.size() == globalPrimalIndex.size())
      ("Number of primals %d, but number of global primals on this rank is %d!\n",
       primals.size(), globalPrimalIndex.size());


    TEST_EXIT_DBG(nOverallPrimals > 0)
      ("There are zero primal nodes in domain!\n");
  }


  void PetscSolverFeti::createDuals()
  {
    FUNCNAME("PetscSolverFeti::createDuals()");
    
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    // === Create for each dual node that is owned by the rank, the set ===
    // === of ranks that contain this node (denoted by W(x_j)).         ===
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    boundaryDofRanks.clear();

    RankToDofContainer& sendDofs = meshDistributor->getSendDofs();
    for (RankToDofContainer::iterator it = sendDofs.begin();
	 it != sendDofs.end(); ++it) {
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt) {
	// If DOF is not primal, i.e., its a dual node
	if (primals.count(**dofIt) == 0) {
	  boundaryDofRanks[**dofIt].insert(mpiRank);
	  boundaryDofRanks[**dofIt].insert(it->first);
	}
      }
    }

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    // === Communicate these sets for all rank owned dual nodes to other ===
    // === ranks that also have this node.                               ===

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    StdMpi<vector<std::set<int> > > stdMpi(meshDistributor->getMpiComm());
    for (RankToDofContainer::iterator it = sendDofs.begin();
	 it != sendDofs.end(); ++it)
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt)
	if (primals.count(**dofIt) == 0)
	  stdMpi.getSendData(it->first).push_back(boundaryDofRanks[**dofIt]);

    stdMpi.updateSendDataSize();

    RankToDofContainer& recvDofs = meshDistributor->getRecvDofs();
    for (RankToDofContainer::iterator it = recvDofs.begin();
	 it != recvDofs.end(); ++it) {
      bool recvFromRank = false;
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt)
	if (primals.count(**dofIt) == 0) {
	  recvFromRank = true;
	  break;
	}

      if (recvFromRank)
	stdMpi.recv(it->first);
    }
    stdMpi.startCommunication();

    for (RankToDofContainer::iterator it = recvDofs.begin();
	 it != recvDofs.end(); ++it) {
      int i = 0;
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt)	
	if (primals.count(**dofIt) == 0)
	  boundaryDofRanks[**dofIt] = stdMpi.getRecvData(it->first)[i++];	      
    }


    // === Create global index of the dual nodes on each rank. ===

    duals.clear();
    globalDualIndex.clear();

    int nRankAllDofs = meshDistributor->getFeSpace()->getAdmin()->getUsedDofs();
    nRankB = nRankAllDofs - primals.size();
    nOverallB = 0;
    rStartB = 0;
    mpi::getDofNumbering(meshDistributor->getMpiComm(),
			 nRankB, rStartB, nOverallB);
    DofContainer allBoundaryDofs;
    meshDistributor->getAllBoundaryDofs(allBoundaryDofs);
    int nRankInteriorDofs = nRankAllDofs - allBoundaryDofs.size();

    int nRankDuals = 0;
    for (DofContainer::iterator it = allBoundaryDofs.begin();
	 it != allBoundaryDofs.end(); ++it) {
      if (primals.count(**it) == 0) {
	duals.insert(**it);
	globalDualIndex[**it] = rStartB + nRankInteriorDofs + nRankDuals;
	nRankDuals++;
      }
    }

    int nOverallDuals = nRankDuals;
    mpi::globalAdd(nOverallDuals);

    MSG_DBG("nRankDuals = %d   nOverallDuals = %d\n",
	    nRankDuals, nOverallDuals);
  }

  
  void PetscSolverFeti::createLagrange()
  {
    FUNCNAME("PetscSolverFeti::createLagrange()");

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    // === Reserve for each dual node, on the rank that owns this node, the ===
    // === appropriate number of Lagrange constraints.                      ===

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    nRankLagrange = 0;
    for (DofIndexSet::iterator it = duals.begin(); it != duals.end(); ++it) {
      if (meshDistributor->getIsRankDof(*it)) {
	dofFirstLagrange[*it] = nRankLagrange;
	int degree = boundaryDofRanks[*it].size();
	nRankLagrange += (degree * (degree - 1)) / 2;
      }
    }

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    // === Get the overall number of Lagrange constraints and create the ===
    // === mapping dofFirstLagrange, that defines for each dual boundary ===
    // === node the first Lagrange constraint global index.              ===

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    nOverallLagrange = 0;
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    rStartLagrange = 0;
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    mpi::getDofNumbering(meshDistributor->getMpiComm(),
			 nRankLagrange, rStartLagrange, nOverallLagrange);

    for (DofIndexSet::iterator it = duals.begin(); it != duals.end(); ++it)
      if (meshDistributor->getIsRankDof(*it))
	dofFirstLagrange[*it] += rStartLagrange;

    MSG_DBG("nRankLagrange = %d  nOverallLagrange = %d\n",
	    nRankLagrange, nOverallLagrange);


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    // === Communicate dofFirstLagrange to all other ranks. ===
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    StdMpi<vector<int> > stdMpi(meshDistributor->getMpiComm());
    RankToDofContainer& sendDofs = meshDistributor->getSendDofs();
    for (RankToDofContainer::iterator it = sendDofs.begin();
	 it != sendDofs.end(); ++it)
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt) {
	if (primals.count(**dofIt) == 0) {
	  TEST_EXIT_DBG(dofFirstLagrange.count(**dofIt))("Should not happen!\n");
	  stdMpi.getSendData(it->first).push_back(dofFirstLagrange[**dofIt]);
	}
      }
    stdMpi.updateSendDataSize();

    RankToDofContainer& recvDofs = meshDistributor->getRecvDofs();
    for (RankToDofContainer::iterator it = recvDofs.begin();
	 it != recvDofs.end(); ++it) {
      bool recvData = false;
      for (DofContainer::iterator dofIt = it->second.begin();
	   dofIt != it->second.end(); ++dofIt)
	if (primals.count(**dofIt) == 0) {
	  recvData = true;
	  break;
	}
	  
      if (recvData)
	stdMpi.recv(it->first);
    }

    stdMpi.startCommunication();

    for (RankToDofContainer::iterator it = recvDofs.begin();
	 it != recvDofs.end(); ++it) {
      int counter = 0;
      for (unsigned int i = 0; i < it->second.size(); i++)
	if (primals.count(*(it->second[i])) == 0)
	  dofFirstLagrange[*(it->second[i])] = stdMpi.getRecvData(it->first)[counter++];
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    }     
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  }


  void PetscSolverFeti::createIndexB()
  {
    FUNCNAME("PetscSolverFeti::createIndeB()");

    globalIndexB.clear();
    DOFAdmin* admin = meshDistributor->getFeSpace()->getAdmin();
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    // === To ensure that all interior node on each rank are listen first in ===
    // === the global index of all B nodes, insert all interior nodes first, ===
    // === without defining a correct index.                                 ===
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    for (int i = 0; i < admin->getUsedSize(); i++)
      if (admin->isDofFree(i) == false && primals.count(i) == 0)
	if (duals.count(i) == 0 && primals.count(i) == 0)
	  globalIndexB[i] = -1;

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    // === Get correct index for all interior nodes. ===

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    int nInterior = 0;
    for (DofMapping::iterator it = globalIndexB.begin(); 
	 it != globalIndexB.end(); ++it) {
      it->second = nInterior + rStartB;
      nInterior++;
    }

    TEST_EXIT_DBG(nInterior + primals.size() + duals.size() == 
		  static_cast<unsigned int>(admin->getUsedDofs()))
      ("Should not happen!\n");

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    // === And finally, add the global indicies of all dual nodes. ===

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    for (DofIndexSet::iterator it = duals.begin();
	 it != duals.end(); ++it)
      globalIndexB[*it] = globalDualIndex[*it];
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  }


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  void PetscSolverFeti::createMatLagrange()
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  {
    FUNCNAME("PetscSolverFeti::createMatLagrange()");

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    // === Create distributed matrix for Lagrange constraints. ===

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    MatCreateMPIAIJ(PETSC_COMM_WORLD,
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		    nRankLagrange * nComponents, 
		    nRankB * nComponents,
		    nOverallLagrange * nComponents, 
		    nOverallB * nComponents,
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		    2, PETSC_NULL, 2, PETSC_NULL,
		    &mat_lagrange);

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    // === Create for all duals the corresponding Lagrange constraints. On ===
    // === each rank we traverse all pairs (n, m) of ranks, with n < m,    ===
    // === that contain this node. If the current rank number is r, and    ===
    // === n == r, the rank sets 1.0 for the corresponding constraint, if  ===
    // === m == r, than the rank sets -1.0 for the corresponding           ===
    // === constraint.                                                     ===

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    for (DofIndexSet::iterator it = duals.begin(); it != duals.end(); ++it) {
      TEST_EXIT_DBG(dofFirstLagrange.count(*it))("Should not happen!\n");
      TEST_EXIT_DBG(boundaryDofRanks.count(*it))("Should not happen!\n");

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      // Global index of the first Lagrange constriant for this node.
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      int index = dofFirstLagrange[*it];
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      // Copy set of all ranks that contain this dual node.
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      vector<int> W(boundaryDofRanks[*it].begin(), boundaryDofRanks[*it].end());
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      // Number of ranks that contain this dual node.
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      int degree = W.size();

      TEST_EXIT_DBG(globalDualIndex.count(*it))("Should not happen!\n");
      int dualCol = globalDualIndex[*it];

      for (int i = 0; i < degree; i++) {
	for (int j = i + 1; j < degree; j++) {
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	  if (W[i] == mpiRank || W[j] == mpiRank) {
	    // Set the constraint for all components of the system.
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	    for (int k = 0; k < nComponents; k++) {
	      int rowIndex = index * nComponents + k;
	      int colIndex = dualCol * nComponents + k;
	      double value = (W[i] == mpiRank ? 1.0 : -1.0);
	      MatSetValue(mat_lagrange, rowIndex, colIndex, value, 
			  INSERT_VALUES);
	    }
	  }

	  index++;
	}
      }
    }

    MatAssemblyBegin(mat_lagrange, MAT_FINAL_ASSEMBLY);
    MatAssemblyEnd(mat_lagrange, MAT_FINAL_ASSEMBLY);
  }


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  void PetscSolverFeti::createSchurPrimalKsp()
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  {
    FUNCNAME("PetscSolverFeti::createSchurPrimal()");

    petscSchurPrimalData.mat_primal_primal = &mat_primal_primal;
    petscSchurPrimalData.mat_primal_b = &mat_primal_b;
    petscSchurPrimalData.mat_b_primal = &mat_b_primal;
    petscSchurPrimalData.ksp_b = &ksp_b;

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    VecDuplicate(f_b, &(petscSchurPrimalData.tmp_vec_b));
    VecDuplicate(f_primal, &(petscSchurPrimalData.tmp_vec_primal));
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    MatCreateShell(PETSC_COMM_WORLD,
		   nRankPrimals * nComponents, nRankPrimals * nComponents,
		   nOverallPrimals * nComponents, nOverallPrimals * nComponents,
		   &petscSchurPrimalData, 
		   &mat_schur_primal);
    MatShellSetOperation(mat_schur_primal, MATOP_MULT, 
			 (void(*)(void))petscMultMatSchurPrimal);

    KSPCreate(PETSC_COMM_WORLD, &ksp_schur_primal);
    KSPSetOperators(ksp_schur_primal, mat_schur_primal, mat_schur_primal, SAME_NONZERO_PATTERN);
    KSPSetOptionsPrefix(ksp_schur_primal, "solver_sp_");
    KSPSetFromOptions(ksp_schur_primal);
  }


  void PetscSolverFeti::destroySchurPrimalKsp()
  {
    FUNCNAME("PetscSolverFeti::destroySchurPrimal()");

    petscSchurPrimalData.mat_primal_primal = PETSC_NULL;
    petscSchurPrimalData.mat_primal_b = PETSC_NULL;
    petscSchurPrimalData.mat_b_primal = PETSC_NULL;
    petscSchurPrimalData.ksp_b = PETSC_NULL;

    VecDestroy(petscSchurPrimalData.tmp_vec_b);
    VecDestroy(petscSchurPrimalData.tmp_vec_primal);

    MatDestroy(mat_schur_primal);
    KSPDestroy(ksp_schur_primal);
  }


  void PetscSolverFeti::createFetiKsp()
  {
    FUNCNAME("PetscSolverFeti::createFetiKsp()");

    petscFetiData.mat_primal_primal = &mat_primal_primal;
    petscFetiData.mat_primal_b = &mat_primal_b;
    petscFetiData.mat_b_primal = &mat_b_primal;
    petscFetiData.mat_lagrange = &mat_lagrange;
    petscFetiData.ksp_b = &ksp_b;
    petscFetiData.ksp_schur_primal = &ksp_schur_primal;


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    VecDuplicate(f_b, &(petscFetiData.tmp_vec_b));
    VecDuplicate(f_primal, &(petscFetiData.tmp_vec_primal));
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    MatGetVecs(mat_lagrange, PETSC_NULL, &(petscFetiData.tmp_vec_lagrange));


    MatCreateShell(PETSC_COMM_WORLD,
		   nRankLagrange, nRankLagrange,
		   nOverallLagrange, nOverallLagrange,
		   &petscFetiData, &mat_feti);
    MatShellSetOperation(mat_feti, MATOP_MULT, (void(*)(void))petscMultMatFeti);


    KSPCreate(PETSC_COMM_WORLD, &ksp_feti);
    KSPSetOperators(ksp_feti, mat_feti, mat_feti, SAME_NONZERO_PATTERN);
    KSPSetOptionsPrefix(ksp_feti, "solver_feti_");
    KSPSetFromOptions(ksp_feti);
  }
  

  void PetscSolverFeti::destroyFetiKsp()
  {
    FUNCNAME("PetscSolverFeti::destroyFetiKsp()");

    petscFetiData.mat_primal_primal = PETSC_NULL;
    petscFetiData.mat_primal_b = PETSC_NULL;
    petscFetiData.mat_b_primal = PETSC_NULL;
    petscFetiData.mat_lagrange = PETSC_NULL;
    petscFetiData.ksp_b = PETSC_NULL;
    petscFetiData.ksp_schur_primal = PETSC_NULL;

    VecDestroy(petscFetiData.tmp_vec_b);
    VecDestroy(petscFetiData.tmp_vec_primal);
    VecDestroy(petscFetiData.tmp_vec_lagrange);

    MatDestroy(mat_feti);
    KSPDestroy(ksp_feti);
  }


  void PetscSolverFeti::recoverSolution(Vec &vec_sol_b,
					Vec &vec_sol_primal,
					SystemVector &vec)
  {
    FUNCNAME("PetscSolverFeti::recoverSolution()");

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    // === Get local part of the solution for B variables. ===
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    PetscScalar *localSolB;
    VecGetArray(vec_sol_b, &localSolB);


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    // === Create scatter to get solutions of all primal nodes that are ===
    // === contained in rank's domain.                                  ===
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    vector<PetscInt> globalIsIndex, localIsIndex;
    globalIsIndex.reserve(globalPrimalIndex.size() * nComponents);
    localIsIndex.reserve(globalPrimalIndex.size() * nComponents);

    {
      int counter = 0;
      for (DofMapping::iterator it = globalPrimalIndex.begin();
	   it != globalPrimalIndex.end(); ++it) {
	for (int i = 0; i < nComponents; i++) {
	  globalIsIndex.push_back(it->second * nComponents + i);
	  localIsIndex.push_back(counter++);
	}
      }
    }
    
    IS globalIs, localIs;
    ISCreateGeneral(PETSC_COMM_SELF, 
		    globalIsIndex.size(), 
		    &(globalIsIndex[0]),
		    PETSC_USE_POINTER,
		    &globalIs);

    ISCreateGeneral(PETSC_COMM_SELF, 
		    localIsIndex.size(), 
		    &(localIsIndex[0]),
		    PETSC_USE_POINTER,
		    &localIs);

    Vec local_sol_primal;
    VecCreateSeq(PETSC_COMM_SELF, localIsIndex.size(), &local_sol_primal);

    VecScatter primalScatter;
    VecScatterCreate(vec_sol_primal, globalIs, local_sol_primal, localIs, &primalScatter);
    VecScatterBegin(primalScatter, vec_sol_primal, local_sol_primal, 
		    INSERT_VALUES, SCATTER_FORWARD);
    VecScatterEnd(primalScatter, vec_sol_primal, local_sol_primal, 
		  INSERT_VALUES, SCATTER_FORWARD);

    ISDestroy(globalIs);
    ISDestroy(localIs);    
    VecScatterDestroy(primalScatter);    

    PetscScalar *localSolPrimal;
    VecGetArray(local_sol_primal, &localSolPrimal);


616
    // === And copy from PETSc local vectors to the DOF vectors. ===
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    for (int i = 0; i < nComponents; i++) {
      DOFVector<double>& dofVec = *(vec.getDOFVector(i));

      for (DofMapping::iterator it = globalIndexB.begin();
	   it != globalIndexB.end(); ++it) {
	int petscIndex = (it->second - rStartB) * nComponents + i;
	dofVec[it->first] = localSolB[petscIndex];
      }

      int counter = 0;
      for (DofMapping::iterator it = globalPrimalIndex.begin();
	   it != globalPrimalIndex.end(); ++it) {
	dofVec[it->first] = localSolPrimal[counter * nComponents + i];
	counter++;
      }
    }



    VecRestoreArray(vec_sol_b, &localSolB);
    VecRestoreArray(local_sol_primal, &localSolPrimal);
    VecDestroy(local_sol_primal);
  }


643 644
  void PetscSolverFeti::fillPetscMatrix(Matrix<DOFMatrix*> *mat, 
					SystemVector *vec)
645 646
  {
    FUNCNAME("PetscSolverFeti::fillPetscMatrix()");   
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648 649 650 651
    nComponents = vec->getSize();

    // === Create all sets and indices. ===

652 653
    updateDofData();

654 655 656 657 658 659 660

    // === Create matrices for the FETI-DP method. ===

    int nRowsRankB = nRankB * nComponents;
    int nRowsOverallB = nOverallB * nComponents;
    int nRowsRankPrimal = nRankPrimals * nComponents;
    int nRowsOverallPrimal = nOverallPrimals * nComponents;
661 662

    MatCreateMPIAIJ(PETSC_COMM_WORLD,
663 664
		    nRowsRankB, nRowsRankB, nRowsOverallB, nRowsOverallB,
		    100, PETSC_NULL, 100, PETSC_NULL, &mat_b_b);
665 666

    MatCreateMPIAIJ(PETSC_COMM_WORLD,
667 668 669
		    nRowsRankPrimal, nRowsRankPrimal, 
		    nRowsOverallPrimal, nRowsOverallPrimal,
		    10, PETSC_NULL, 10, PETSC_NULL, &mat_primal_primal);
670 671

    MatCreateMPIAIJ(PETSC_COMM_WORLD,
672 673 674
		    nRowsRankB, nRowsRankPrimal, 
		    nRowsOverallB, nRowsOverallPrimal,
		    100, PETSC_NULL, 100, PETSC_NULL, &mat_b_primal);
675 676

    MatCreateMPIAIJ(PETSC_COMM_WORLD,
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		    nRowsRankPrimal, nRowsRankB,
		    nRowsOverallPrimal, nRowsOverallB,
		    100, PETSC_NULL, 100, PETSC_NULL, &mat_primal_b);

    
    // === Prepare traverse of sequentially created matrices. ===
683 684 685 686 687 688 689 690 691 692 693 694 695 696 697

    using mtl::tag::row; using mtl::tag::nz; using mtl::begin; using mtl::end;
    namespace traits = mtl::traits;
    typedef DOFMatrix::base_matrix_type Matrix;

    typedef traits::range_generator<row, Matrix>::type cursor_type;
    typedef traits::range_generator<nz, cursor_type>::type icursor_type;

    vector<int> cols, colsOther;
    vector<double> values, valuesOther;
    cols.reserve(300);
    colsOther.reserve(300);
    values.reserve(300);
    valuesOther.reserve(300);

698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735

    // === Traverse all sequentially created matrices and add the values to ===
    // === the global PETSc matrices.                                       ===

    for (int i = 0; i < nComponents; i++) {
      for (int j = 0; j < nComponents; j++) {
	if (!(*mat)[i][j])
	  continue;

	traits::col<Matrix>::type col((*mat)[i][j]->getBaseMatrix());
	traits::const_value<Matrix>::type value((*mat)[i][j]->getBaseMatrix());
	
	// Traverse all rows.
	for (cursor_type cursor = begin<row>((*mat)[i][j]->getBaseMatrix()), 
	       cend = end<row>((*mat)[i][j]->getBaseMatrix()); cursor != cend; ++cursor) {
	  bool rowPrimal = primals.count(*cursor) != 0;
	  
	  cols.clear();
	  values.clear();
	  
	  colsOther.clear();
	  valuesOther.clear();
	  
	  // Traverse all columns.
	  for (icursor_type icursor = begin<nz>(cursor), icend = end<nz>(cursor); 
	       icursor != icend; ++icursor) {

	    if (primals.count(col(*icursor)) != 0) {
	      // Column is a primal variable.

	      TEST_EXIT_DBG(globalPrimalIndex.count(col(*icursor)))
		("No global primal index for DOF %d!\n", col(*icursor));
	      
	      int colIndex = globalPrimalIndex[col(*icursor)] * nComponents + j;
	      
	      if (rowPrimal) {
		cols.push_back(colIndex);
		values.push_back(value(*icursor));
736
	      } else {
737 738 739 740 741 742 743 744
		colsOther.push_back(colIndex);
		valuesOther.push_back(value(*icursor));
	      }
	    } else {
	      // Column is not a primal variable.

	      TEST_EXIT_DBG(globalIndexB.count(col(*icursor)))
		("No global B index for DOF %d!\n", col(*icursor));
745
	      
746 747 748 749 750 751 752 753
	      int colIndex = globalIndexB[col(*icursor)] * nComponents + j;

	      if (rowPrimal) {
		colsOther.push_back(colIndex);
		valuesOther.push_back(value(*icursor));
	      } else {
		cols.push_back(colIndex);
		values.push_back(value(*icursor));
754 755
	      }
	    }
756
	  }
757

758 759 760
	  if (rowPrimal) {
	    TEST_EXIT_DBG(globalPrimalIndex.count(*cursor))
	      ("Should not happen!\n");
761

762 763 764
	    int rowIndex = globalPrimalIndex[*cursor] * nComponents + i;
	    MatSetValues(mat_primal_primal, 1, &rowIndex, cols.size(),
			 &(cols[0]), &(values[0]), ADD_VALUES);
765

766 767 768 769 770 771
	    if (colsOther.size())
	      MatSetValues(mat_primal_b, 1, &rowIndex, colsOther.size(),
			   &(colsOther[0]), &(valuesOther[0]), ADD_VALUES);
	  } else {
	    TEST_EXIT_DBG(globalIndexB.count(*cursor))
	      ("Should not happen!\n");
772

773 774 775
	    int rowIndex = globalIndexB[*cursor] * nComponents + i;
	    MatSetValues(mat_b_b, 1, &rowIndex, cols.size(),
			 &(cols[0]), &(values[0]), ADD_VALUES);
776

777 778 779 780 781 782 783 784
	    if (colsOther.size())
	      MatSetValues(mat_b_primal, 1, &rowIndex, colsOther.size(),
			   &(colsOther[0]), &(valuesOther[0]), ADD_VALUES);
	  }
	} 
      }
    }
    
785

786
    // === Start global assembly procedure. ===
787 788 789 790 791 792 793 794 795 796 797 798 799 800

    MatAssemblyBegin(mat_b_b, MAT_FINAL_ASSEMBLY);
    MatAssemblyEnd(mat_b_b, MAT_FINAL_ASSEMBLY);

    MatAssemblyBegin(mat_primal_primal, MAT_FINAL_ASSEMBLY);
    MatAssemblyEnd(mat_primal_primal, MAT_FINAL_ASSEMBLY);

    MatAssemblyBegin(mat_b_primal, MAT_FINAL_ASSEMBLY);
    MatAssemblyEnd(mat_b_primal, MAT_FINAL_ASSEMBLY);

    MatAssemblyBegin(mat_primal_b, MAT_FINAL_ASSEMBLY);
    MatAssemblyEnd(mat_primal_b, MAT_FINAL_ASSEMBLY);
	  

801
    // === Create and fill PETSc's right hand side vectors. ===
802

803 804 805
    VecCreate(PETSC_COMM_WORLD, &f_b);
    VecSetSizes(f_b, nRankB * nComponents, nOverallB * nComponents);
    VecSetType(f_b, VECMPI);
806

807 808
    VecCreate(PETSC_COMM_WORLD, &f_primal);
    VecSetSizes(f_primal, nRankPrimals * nComponents, 
809
		nOverallPrimals * nComponents);
810
    VecSetType(f_primal, VECMPI);
811 812 813 814 815 816 817 818 819 820 821
    
    for (int i = 0; i < nComponents; i++) {
      DOFVector<double>::Iterator dofIt(vec->getDOFVector(i), USED_DOFS);
      for (dofIt.reset(); !dofIt.end(); ++dofIt) {
	int index = dofIt.getDOFIndex();
	if (primals.count(index)) {
	  TEST_EXIT_DBG(globalPrimalIndex.count(index))
	    ("Should not happen!\n");

	  index = globalPrimalIndex[index] * nComponents + i;
	  double value = *dofIt;
822
	  VecSetValues(f_primal, 1, &index, &value, ADD_VALUES);
823 824 825 826 827 828
	} else {
	  TEST_EXIT_DBG(globalIndexB.count(index))
	    ("Should not happen!\n");

	  index = globalIndexB[index] * nComponents + i;
	  double value = *dofIt;
829
	  VecSetValues(f_b, 1, &index, &value, ADD_VALUES);
830 831 832 833
	}      
      }
    }

834 835
    VecAssemblyBegin(f_b);
    VecAssemblyEnd(f_b);
836

837 838
    VecAssemblyBegin(f_primal);
    VecAssemblyEnd(f_primal);
839 840


841
    // === Create and fill PETSc matrix for Lagrange constraints. ===
842

843
    createMatLagrange();
844 845

    
846 847 848 849 850 851
    // === Create PETSc solver for the Schur complement on primal variables. ===
    
    createSchurPrimalKsp();


    // === Create PETSc solver for the FETI-DP operator. ===
852 853

    createFetiKsp();
854 855 856
  }


857
  void PetscSolverFeti::solveFetiMatrix(SystemVector &vec)
858
  {
859
    FUNCNAME("PetscSolverFeti::solveFetiMatrix()");
860

861 862 863
    // Create transpose of Lagrange matrix.
    Mat mat_lagrange_transpose;
    MatTranspose(mat_lagrange, MAT_INITIAL_MATRIX, &mat_lagrange_transpose);
864 865


866
    // === Create nested matrix which will contain the overall FETI system. ===
867

868 869 870 871 872 873 874 875 876 877 878
    Mat A;
    Mat nestedA[3][3];
    nestedA[0][0] = mat_b_b;
    nestedA[0][1] = mat_b_primal;
    nestedA[0][2] = mat_lagrange_transpose;
    nestedA[1][0] = mat_primal_b;
    nestedA[1][1] = mat_primal_primal;
    nestedA[1][2] = PETSC_NULL;
    nestedA[2][0] = mat_lagrange;
    nestedA[2][1] = PETSC_NULL;
    nestedA[2][2] = PETSC_NULL;
879

880
    MatCreateNest(PETSC_COMM_WORLD, 3, PETSC_NULL, 3, PETSC_NULL, &(nestedA[0][0]), &A);
881

882 883 884
    MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);
    MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);
  
885 886


887 888 889
    int nRankNest = (nRankB + nRankPrimals) * nComponents + nRankLagrange;    
    int nOverallNest = (nOverallB + nOverallPrimals) * nComponents + nOverallLagrange;
    int rStartNest = (rStartB + rStartPrimals) * nComponents + rStartLagrange;
890

891 892
    {
      // === Test some matrix sizes. ===
893

894 895 896 897 898
      int matRow, matCol;
      MatGetLocalSize(A, &matRow, &matCol);
      TEST_EXIT_DBG(matRow == nRankNest)("Should not happen!\n");
      mpi::globalAdd(matRow);
      TEST_EXIT_DBG(matRow == nOverallNest)("Should not happen!\n");
899

900 901 902
      MatGetOwnershipRange(A, &matRow, &matCol);
      TEST_EXIT_DBG(matRow == rStartNest)("Should not happen!\n");
    }
903

904 905 906 907 908 909 910 911 912 913 914 915
    // === Create rhs and solution vectors for the overall FETI system. ===

    Vec f;
    VecCreate(PETSC_COMM_WORLD, &f);
    VecSetSizes(f, nRankNest, nOverallNest);
    VecSetType(f, VECMPI);

    Vec b;
    VecDuplicate(f, &b);

    
    // === Fill rhs vector by coping the primal and non primal PETSc vectors. ===
916

917 918
    PetscScalar *local_f_b;
    VecGetArray(f_b, &local_f_b);
919

920 921
    PetscScalar *local_f_primal;
    VecGetArray(f_primal, &local_f_primal);
922

923 924 925 926 927 928 929
    {
      int size;
      VecGetLocalSize(f_b, &size);
      TEST_EXIT_DBG(size == nRankB * nComponents)("Should not happen!\n");
      VecGetLocalSize(f_primal, &size);
      TEST_EXIT_DBG(size == nRankPrimals * nComponents)("Should not happen!\n");
    }
930

931 932
    PetscScalar *local_f;
    VecGetArray(f, &local_f);
933

934 935 936 937 938
    int index = 0;
    for (int i = 0; i < nRankB * nComponents; i++)
      local_f[index++] = local_f_b[i];
    for (int i = 0; i < nRankPrimals * nComponents; i++)
      local_f[index++] = local_f_primal[i];
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940 941 942
    VecRestoreArray(f, &local_f);  
    VecRestoreArray(f_b, &local_f_b);
    VecRestoreArray(f_primal, &local_f_primal);
943

944 945
    
    // === Create solver and solve the overall FETI system. ===
946

947 948 949 950
    KSP ksp;
    KSPCreate(PETSC_COMM_WORLD, &ksp);
    KSPSetOperators(ksp, A, A, SAME_NONZERO_PATTERN);
    KSPSetFromOptions(ksp);
951 952


953
    KSPSolve(ksp, f, b);
954 955


956 957 958 959 960
    // === Reconstruct FETI solution vectors. ===
    
    Vec u_b, u_primal;
    VecDuplicate(f_b, &u_b);
    VecDuplicate(f_primal, &u_primal);
961 962
    

963 964
    PetscScalar *local_b;
    VecGetArray(b, &local_b);
965

966 967
    PetscScalar *local_u_b;
    VecGetArray(u_b, &local_u_b);
968

969 970
    PetscScalar *local_u_primal;
    VecGetArray(u_primal, &local_u_primal);
971

972 973 974 975 976
    index = 0;
    for (int i = 0; i < nRankB * nComponents; i++)
      local_u_b[i] = local_b[index++];
    for (int i = 0; i < nRankPrimals * nComponents; i++)
      local_u_primal[i] = local_b[index++];
977

978 979 980
    VecRestoreArray(f, &local_b);
    VecRestoreArray(u_b, &local_u_b);
    VecRestoreArray(u_primal, &local_u_primal);
981

982
    recoverSolution(u_b, u_primal, vec);
983

984 985 986 987
    VecDestroy(u_b);
    VecDestroy(u_primal);
    VecDestroy(b);
    VecDestroy(f);
988

989 990
    KSPDestroy(ksp);
  }
991 992


993 994 995
  void PetscSolverFeti::solveReducedFetiMatrix(SystemVector &vec)
  {
    FUNCNAME("PetscSolverFeti::solveReducedFetiMatrix()");
996

997
    // === Create solver for the non primal (thus local) variables. ===
998

999 1000 1001 1002 1003 1004 1005
    KSPCreate(PETSC_COMM_WORLD, &ksp_b);
    KSPSetOperators(ksp_b, mat_b_b, mat_b_b, SAME_NONZERO_PATTERN);
    KSPSetOptionsPrefix(ksp_b, "solver_b_");
    KSPSetFromOptions(ksp_b);

    // RHS and solution vector.
    Vec vec_rhs;
1006

1007 1008 1009 1010 1011 1012 1013 1014
    // Some temporary vectors.
    Vec tmp_b0, tmp_b1, tmp_lagrange0, tmp_primal0, tmp_primal1;
    MatGetVecs(mat_lagrange, PETSC_NULL, &tmp_lagrange0);
    MatGetVecs(mat_lagrange, PETSC_NULL, &vec_rhs);
    MatGetVecs(mat_b_b, PETSC_NULL, &tmp_b0);
    MatGetVecs(mat_b_b, PETSC_NULL, &tmp_b1);
    MatGetVecs(mat_primal_primal, PETSC_NULL, &tmp_primal0);
    MatGetVecs(mat_primal_primal, PETSC_NULL, &tmp_primal1);
1015 1016


1017
    // === Create new rhs ===
1018

1019 1020 1021
    // vec_rhs = L * inv(K_BB) * f_b
    KSPSolve(ksp_b, f_b, tmp_b0);
    MatMult(mat_lagrange, tmp_b0, vec_rhs);
1022

1023 1024
    // tmp_primal0 = M_PiB * inv(K_BB) * f_b
    MatMult(mat_primal_b, tmp_b0, tmp_primal0);
1025

1026 1027
    // tmp_primal0 = f_Pi - M_PiB * inv(K_BB) * f_b
    VecAXPBY(tmp_primal0, -1.0, 1.0, f_primal);
1028

1029 1030
    // tmp_primal0 = inv(S_PiPi) (f_Pi - M_PiB * inv(K_BB) * f_b)
    KSPSolve(ksp_schur_primal, tmp_primal0, tmp_primal0);
1031

1032 1033 1034 1035
    //
    MatMult(mat_b_primal, tmp_primal0, tmp_b0);
    KSPSolve(ksp_b, tmp_b0, tmp_b0);
    MatMult(mat_lagrange, tmp_b0, tmp_lagrange0);
1036

1037 1038
    //
    VecAXPBY(vec_rhs, 1.0, 1.0, tmp_lagrange0);
1039 1040


1041
    // === Solve with FETI-DP operator. ===
1042

1043
    KSPSolve(ksp_feti, vec_rhs, vec_rhs);
1044 1045

   
1046
    // === Solve for u_primals. ===
1047

1048
    VecCopy(f_primal, tmp_primal0);
1049

1050 1051
    KSPSolve(ksp_b, f_b, tmp_b0);
    MatMult(mat_primal_b, tmp_b0, tmp_primal1);
1052

1053
    VecAXPBY(tmp_primal0, -1.0, 1.0, tmp_primal1);
1054

1055 1056 1057
    MatMultTranspose(mat_lagrange, vec_rhs, tmp_b0);
    KSPSolve(ksp_b, tmp_b0, tmp_b0);
    MatMult(mat_primal_b, tmp_b0, tmp_primal1);
1058

1059 1060
    VecAXPBY(tmp_primal0, 1.0, 1.0, tmp_primal1);
    KSPSolve(ksp_schur_primal, tmp_primal0, tmp_primal0);
1061 1062

    
1063
    // === Solve for u_b. ===
1064

1065 1066 1067
    VecCopy(f_b, tmp_b0);
    MatMultTranspose(mat_lagrange, vec_rhs, tmp_b1);
    VecAXPBY(tmp_b0, -1.0, 1.0, tmp_b1);
1068

1069 1070
    MatMult(mat_b_primal, tmp_primal0, tmp_b1);
    VecAXPBY(tmp_b0, -1.0, 1.0, tmp_b1);
1071

1072
    KSPSolve(ksp_b, tmp_b0, tmp_b0);
1073 1074


1075
    // === And recover AMDiS solution vectors. ===
1076
    
1077
    recoverSolution(tmp_b0, tmp_primal0, vec);
1078 1079


1080
    // === Destroy all data structures. ===
1081
    
1082 1083 1084 1085 1086 1087
    VecDestroy(vec_rhs);
    VecDestroy(tmp_b0);
    VecDestroy(tmp_b1);
    VecDestroy(tmp_lagrange0);
    VecDestroy(tmp_primal0);
    VecDestroy(tmp_primal1);
1088 1089
	    

1090
    KSPDestroy(ksp_b);
1091

1092 1093 1094 1095 1096
    MatDestroy(mat_b_b);
    MatDestroy(mat_primal_primal);
    MatDestroy(mat_b_primal);
    MatDestroy(mat_primal_b);
    MatDestroy(mat_lagrange);
1097

1098 1099
    VecDestroy(f_b);
    VecDestroy(f_primal);
1100

1101
    destroySchurPrimalKsp();
1102

1103 1104
    destroyFetiKsp();   
  }
1105

1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121

  void PetscSolverFeti::solvePetscMatrix(SystemVector &vec, AdaptInfo *adaptInfo)
  {
    FUNCNAME("PetscSolverFeti::solvePetscMatrix()");

    int debug = 0;
    Parameters::get("parallel->debug feti", debug);

    if (debug) {
      WARNING("FETI matrix is solved globally, thus without reducing to the lagrange multipliers!\n");

      solveFetiMatrix(vec);
    } else {
      solveReducedFetiMatrix(vec);
    }
      
1122 1123 1124 1125
  }
#endif

}