C++ AztecOO::Iterate方法代码示例

int shylu_local_solve<Epetra_CrsMatrix, Epetra_MultiVector>
(
    shylu_symbolic<Epetra_CrsMatrix,Epetra_MultiVector> *ssym,
    shylu_data<Epetra_CrsMatrix,Epetra_MultiVector> *data,
    shylu_config<Epetra_CrsMatrix,Epetra_MultiVector> *config,
    const Epetra_MultiVector& X,
    Epetra_MultiVector& Y
)
{
    int err;
#ifndef NDEBUG
    int nvectors = X.NumVectors();
    assert (nvectors == data->localrhs->NumVectors());
#endif // NDEBUG

    // Initialize the X vector for iterative solver
    data->Xs->PutScalar(0.0);

    // Get local portion of X
    data->localrhs->Import(X, *(data->BdImporter), Insert);


    data->localrhs->Print(std::cout);
    std::cout << " " << std::endl;
    data->locallhs->Print(std::cout);

    // locallhs is z in paper
    if (config->amesosForDiagonal) {
        std::cout << "calling amesos for diagon" << endl;
        ssym->OrigLP->SetRHS((data->localrhs).getRawPtr());
        ssym->OrigLP->SetLHS((data->locallhs).getRawPtr());
        std::cout << "set RHS and LHS " << std::endl;
        ssym->ReIdx_LP->fwd();
        ssym->Solver->Solve();
    }
    else {
        ssym->ifSolver->ApplyInverse(*(data->localrhs), *(data->locallhs));
    }

    err = ssym->R->Multiply(false, *(data->locallhs), *(data->temp1));
    assert (err == 0);

    // Export temp1 to a dist vector - temp2
    data->temp2->Import(*(data->temp1), *(data->DistImporter), Insert);

    //Epetra_MultiVector Bs(SMap, nvectors); // b_2 - R * z in ShyLU paper
    data->Bs->Import(X, *(data->BsImporter), Insert);
    data->Bs->Update(-1.0, *(data->temp2), 1.0);

    AztecOO *solver = 0;
    Epetra_LinearProblem Problem(data->Sbar.get(),
                                 (data->Xs).getRawPtr(), (data->Bs).getRawPtr());
    if ((config->schurSolver == "G") || (config->schurSolver == "IQR"))
    {
        IFPACK_CHK_ERR(data->iqrSolver->Solve(*(data->schur_op),
                                              *(data->Bs), *(data->Xs)));
    }
    else if (config->schurSolver == "Amesos")
    {
        Amesos_BaseSolver *solver2 = data->dsolver;
        data->OrigLP2->SetLHS((data->Xs).getRawPtr());
        data->OrigLP2->SetRHS((data->Bs).getRawPtr());
        data->ReIdx_LP2->fwd();
        //cout << "Calling solve *****************************" << endl;
        solver2->Solve();
        //cout << "Out of solve *****************************" << endl;
    }
    else
    {
        if (config->libName == "Belos")
        {
            solver = data->innersolver;
            solver->SetLHS((data->Xs).getRawPtr());
            solver->SetRHS((data->Bs).getRawPtr());
        }
        else
        {
            // See the comment above on why we are not able to reuse the solver
            // when outer solve is AztecOO as well.
            solver = new AztecOO();
            //solver.SetPrecOperator(precop_);
            solver->SetAztecOption(AZ_solver, AZ_gmres);
            // Do not use AZ_none
            solver->SetAztecOption(AZ_precond, AZ_dom_decomp);
            //solver->SetAztecOption(AZ_precond, AZ_none);
            //solver->SetAztecOption(AZ_precond, AZ_Jacobi);
            ////solver->SetAztecOption(AZ_precond, AZ_Neumann);
            //solver->SetAztecOption(AZ_overlap, 3);
            //solver->SetAztecOption(AZ_subdomain_solve, AZ_ilu);
            //solver->SetAztecOption(AZ_output, AZ_all);
            //solver->SetAztecOption(AZ_diagnostics, AZ_all);
            solver->SetProblem(Problem);
        }

        // What should be a good inner_tolerance :-) ?
        solver->Iterate(config->inner_maxiters, config->inner_tolerance);
    }

    // Import Xs locally
    data->LocalXs->Import(*(data->Xs), *(data->XsImporter), Insert);
//.........这里部分代码省略.........

int main(int argc, char *argv[]) {

#ifdef HAVE_MPI
  MPI_Init(&argc,&argv);
  Epetra_MpiComm Comm (MPI_COMM_WORLD);
#else
  Epetra_SerialComm Comm;
#endif

  Teuchos::ParameterList GaleriList;
  int nx = 30; 

  GaleriList.set("nx", nx);
  //  GaleriList.set("ny", nx * Comm.NumProc());
  GaleriList.set("ny", nx);
  GaleriList.set("mx", 1);
  GaleriList.set("my", Comm.NumProc());
  GaleriList.set("alpha", .0);
  GaleriList.set("diff", 1.0);
  GaleriList.set("conv", 100.0);

  Teuchos::RefCountPtr<Epetra_Map> Map = Teuchos::rcp( Galeri::CreateMap("Cartesian2D", Comm, GaleriList) );
  Teuchos::RefCountPtr<Epetra_CrsMatrix> A = Teuchos::rcp( Galeri::CreateCrsMatrix("UniFlow2D", &*Map, GaleriList) );
  Teuchos::RefCountPtr<Epetra_MultiVector> LHS = Teuchos::rcp( new Epetra_MultiVector(*Map, 1) );
  Teuchos::RefCountPtr<Epetra_MultiVector> RHS = Teuchos::rcp( new Epetra_MultiVector(*Map, 1) );
  LHS->PutScalar(0.0); RHS->Random();
  Ifpack Factory;  
  int Niters = 100;

  // ============================= //
  // Construct IHSS preconditioner //
  // ============================= //
  Teuchos::RefCountPtr<Ifpack_Preconditioner> Prec = Teuchos::rcp( Factory.Create("IHSS", &*A,0) );
  Teuchos::ParameterList List;
  List.set("ihss: hermetian type","ILU");
  List.set("ihss: skew hermetian type","ILU");
  List.set("ihss: ratio eigenvalue",100.0);
  // Could set sublist values here to better control the ILU, but this isn't needed for this example.
  IFPACK_CHK_ERR(Prec->SetParameters(List));
  IFPACK_CHK_ERR(Prec->Compute());

  // ============================= //
  // Create solver Object          //
  // ============================= //

  AztecOO solver;
  solver.SetUserMatrix(&*A);
  solver.SetLHS(&*LHS);
  solver.SetRHS(&*RHS);
  solver.SetAztecOption(AZ_solver,AZ_gmres);
  solver.SetPrecOperator(&*Prec);
  solver.SetAztecOption(AZ_output, 1); 
  solver.Iterate(Niters, 1e-8);

  // ============================= //
  // Construct SORa preconditioner //
  // ============================= //
  Teuchos::RefCountPtr<Ifpack_Preconditioner> Prec2 = Teuchos::rcp( Factory.Create("SORa", &*A,0) );
  Teuchos::ParameterList List2;
  List2.set("sora: sweeps",1);
  // Could set sublist values here to better control the ILU, but this isn't needed for this example.
  IFPACK_CHK_ERR(Prec2->SetParameters(List2));
  IFPACK_CHK_ERR(Prec2->Compute());

  // ============================= //
  // Create solver Object          //
  // ============================= //
  AztecOO solver2;
  LHS->PutScalar(0.0);
  solver2.SetUserMatrix(&*A);
  solver2.SetLHS(&*LHS);
  solver2.SetRHS(&*RHS);
  solver2.SetAztecOption(AZ_solver,AZ_gmres);
  solver2.SetPrecOperator(&*Prec2);
  solver2.SetAztecOption(AZ_output, 1); 
  solver2.Iterate(Niters, 1e-8);

#ifdef HAVE_MPI
  MPI_Finalize() ;
#endif

  return(EXIT_SUCCESS);
}

//.........这里部分代码省略.........
        data->LP2->SetRHS(&Bs);
        //cout << "Calling solve *****************************" << endl;
        solver2->Solve();
        //cout << "Out of solve *****************************" << endl;
    }
    else
    {
        if (config->libName == "Belos")
        {
            solver = data->innersolver;
            solver->SetLHS(&Xs);
            solver->SetRHS(&Bs);
        }
        else
        {
            // See the comment above on why we are not able to reuse the solver
            // when outer solve is AztecOO as well.
            solver = new AztecOO();
            //solver.SetPrecOperator(precop_);
            solver->SetAztecOption(AZ_solver, AZ_gmres);
            // Do not use AZ_none
            solver->SetAztecOption(AZ_precond, AZ_dom_decomp);
            //solver->SetAztecOption(AZ_precond, AZ_none);
            //solver->SetAztecOption(AZ_precond, AZ_Jacobi);
            ////solver->SetAztecOption(AZ_precond, AZ_Neumann);
            //solver->SetAztecOption(AZ_overlap, 3);
            //solver->SetAztecOption(AZ_subdomain_solve, AZ_ilu);
            //solver->SetAztecOption(AZ_output, AZ_all);
            //solver->SetAztecOption(AZ_diagnostics, AZ_all);
            solver->SetProblem(Problem);
        }

        // What should be a good inner_tolerance :-) ?
        solver->Iterate(config->inner_maxiters, config->inner_tolerance);
    }

    Epetra_MultiVector temp(BdMap, nvectors);
    ssym->C->Multiply(false, Xs, temp);
    temp.Update(1.0, Bd, -1.0);

    //Epetra_SerialComm LComm;        // Use Serial Comm for the local vectors.
    //Epetra_Map LocalBdMap(-1, data->Dnr, data->DRowElems, 0, LComm);
    //Epetra_MultiVector localrhs(LocalBdMap, nvectors);
    //Epetra_MultiVector locallhs(LocalBdMap, nvectors);

    //int lda;
    //double *values;
    err = temp.ExtractView(&values, &lda);
    assert (err == 0);
    //int nrows = data->Cptr->RowMap().NumMyElements();

    // copy to local vector //TODO: OMP ?
    assert(lda == nrows);
    for (int v = 0; v < nvectors; v++)
    {
        for (int i = 0; i < nrows; i++)
        {
            err = localrhs.ReplaceMyValue(i, v, values[i+v*lda]);
            assert (err == 0);
        }
    }

    if (config->amesosForDiagonal)
    {
        ssym->LP->SetRHS(&localrhs);
        ssym->LP->SetLHS(&locallhs);

int main(int argc, char *argv[]) {

#ifdef HAVE_MPI
  MPI_Init(&argc,&argv);
  Epetra_MpiComm Comm (MPI_COMM_WORLD);
#else
  Epetra_SerialComm Comm;
#endif

  int MyPID = Comm.MyPID();
  bool verbose = false; 
  if (MyPID==0) verbose = true;

  Teuchos::ParameterList GaleriList;
  int nx = 30; 

  GaleriList.set("nx", nx);
  GaleriList.set("ny", nx * Comm.NumProc());
  GaleriList.set("mx", 1);
  GaleriList.set("my", Comm.NumProc());
  Teuchos::RefCountPtr<Epetra_Map> Map = Teuchos::rcp( Galeri::CreateMap("Cartesian2D", Comm, GaleriList) );
  Teuchos::RefCountPtr<Epetra_CrsMatrix> A = Teuchos::rcp( Galeri::CreateCrsMatrix("Laplace2D", &*Map, GaleriList) );
  Teuchos::RefCountPtr<Epetra_MultiVector> LHS = Teuchos::rcp( new Epetra_MultiVector(*Map, 1) );
  Teuchos::RefCountPtr<Epetra_MultiVector> RHS = Teuchos::rcp( new Epetra_MultiVector(*Map, 1) );
  LHS->PutScalar(0.0); RHS->Random();

  // ============================ //
  // Construct ILU preconditioner //
  // ---------------------------- //

  // I wanna test funky values to be sure that they have the same
  // influence on the algorithms, both old and new
  int    LevelFill = 2;
  double DropTol = 0.3333;
  double Athresh = 0.0123;
  double Rthresh = 0.9876;
  double Relax   = 0.1;
  int    Overlap = 2;
  
  Teuchos::RefCountPtr<Ifpack_IlukGraph> Graph;
  Teuchos::RefCountPtr<Ifpack_CrsRiluk> RILU;

  Graph = Teuchos::rcp( new Ifpack_IlukGraph(A->Graph(), LevelFill, Overlap) );
  int ierr;
  ierr = Graph->ConstructFilledGraph();
  IFPACK_CHK_ERR(ierr);

  RILU = Teuchos::rcp( new Ifpack_CrsRiluk(*Graph) );
  RILU->SetAbsoluteThreshold(Athresh);
  RILU->SetRelativeThreshold(Rthresh);
  RILU->SetRelaxValue(Relax);
  int initerr = RILU->InitValues(*A);
  if (initerr!=0) cout << Comm << "*ERR* InitValues = " << initerr;

  RILU->Factor();

  // Define label for printing out during the solve phase
  string label = "Ifpack_CrsRiluk Preconditioner: LevelFill = " + toString(LevelFill) +
                                                 " Overlap = " + toString(Overlap) +
                                                 " Athresh = " + toString(Athresh) +
                                                 " Rthresh = " + toString(Rthresh);
  // Here we create an AztecOO object
  LHS->PutScalar(0.0);

  int Niters = 1200;

  AztecOO solver;
  solver.SetUserMatrix(&*A);
  solver.SetLHS(&*LHS);
  solver.SetRHS(&*RHS);
  solver.SetAztecOption(AZ_solver,AZ_gmres);
  solver.SetPrecOperator(&*RILU);
  solver.SetAztecOption(AZ_output, 16); 
  solver.Iterate(Niters, 5.0e-5);

  int OldIters = solver.NumIters();

  // now rebuild the same preconditioner using RILU, we expect the same
  // number of iterations

  Ifpack Factory;
  Teuchos::RefCountPtr<Ifpack_Preconditioner> Prec = Teuchos::rcp( Factory.Create("ILU", &*A, Overlap) );

  Teuchos::ParameterList List;
  List.get("fact: level-of-fill", LevelFill);
  List.get("fact: drop tolerance", DropTol);
  List.get("fact: absolute threshold", Athresh);
  List.get("fact: relative threshold", Rthresh);
  List.get("fact: relax value", Relax);

  IFPACK_CHK_ERR(Prec->SetParameters(List));
  IFPACK_CHK_ERR(Prec->Compute());

  // Here we create an AztecOO object
  LHS->PutScalar(0.0);

  solver.SetUserMatrix(&*A);
  solver.SetLHS(&*LHS);
  solver.SetRHS(&*RHS);
  solver.SetAztecOption(AZ_solver,AZ_gmres);
//.........这里部分代码省略.........