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;
// The problem is defined on a 2D grid, global size is nx * nx.
int nx = 30;
Teuchos::ParameterList GaleriList;
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 Condest;
Teuchos::RefCountPtr<Ifpack_CrsIct> ICT;
ICT = Teuchos::rcp( new Ifpack_CrsIct(*A,DropTol,LevelFill) );
ICT->SetAbsoluteThreshold(0.00123);
ICT->SetRelativeThreshold(0.9876);
// Init values from A
ICT->InitValues(*A);
// compute the factors
ICT->Factor();
// and now estimate the condition number
ICT->Condest(false,Condest);
if( Comm.MyPID() == 0 ) {
cout << "Condition number estimate (level-of-fill = "
<< LevelFill << ") = " << Condest << endl;
}
// Define label for printing out during the solve phase
string label = "Ifpack_CrsIct Preconditioner: LevelFill = " + toString(LevelFill) +
" Overlap = 0";
ICT->SetLabel(label.c_str());
// 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_cg);
solver.SetPrecOperator(&*ICT);
solver.SetAztecOption(AZ_output, 16);
solver.Iterate(Niters, 5.0e-5);
int OldIters = solver.NumIters();
// now rebuild the same preconditioner using ICT, we expect the same
// number of iterations
Ifpack Factory;
Teuchos::RefCountPtr<Ifpack_Preconditioner> Prec = Teuchos::rcp( Factory.Create("IC", &*A) );
Teuchos::ParameterList List;
List.get("fact: level-of-fill", 2);
List.get("fact: drop tolerance", 0.3333);
List.get("fact: absolute threshold", 0.00123);
List.get("fact: relative threshold", 0.9876);
List.get("fact: relaxation value", 0.0);
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_cg);
solver.SetPrecOperator(&*Prec);
solver.SetAztecOption(AZ_output, 16);
solver.Iterate(Niters, 5.0e-5);
int NewIters = solver.NumIters();
if (OldIters != NewIters)
IFPACK_CHK_ERR(-1);
#ifdef HAVE_MPI
MPI_Finalize() ;
#endif
return(EXIT_SUCCESS);
}
int main(int argc, char *argv[]) {
#ifdef HAVE_MPI
MPI_Init(&argc,&argv);
Epetra_MpiComm Comm (MPI_COMM_WORLD);
#else
Epetra_SerialComm Comm;
#endif
// The problem is defined on a 2D grid, global size is nx * nx.
int nx = 30;
Teuchos::ParameterList GaleriList;
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();
// ========================================= //
// Compare IC preconditioners to no precond. //
// ----------------------------------------- //
const double tol = 1e-5;
const int maxIter = 500;
// Baseline: No preconditioning
// Compute number of iterations, to compare to IC later.
// Here we create an AztecOO object
LHS->PutScalar(0.0);
AztecOO solver;
solver.SetUserMatrix(&*A);
solver.SetLHS(&*LHS);
solver.SetRHS(&*RHS);
solver.SetAztecOption(AZ_solver,AZ_cg);
//solver.SetPrecOperator(&*PrecDiag);
solver.SetAztecOption(AZ_output, 16);
solver.Iterate(maxIter, tol);
int Iters = solver.NumIters();
//cout << "No preconditioner iterations: " << Iters << endl;
#if 0
// Not sure how to use Ifpack_CrsRick - leave out for now.
//
// 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 Condest;
Teuchos::RefCountPtr<Ifpack_CrsRick> IC;
Ifpack_IlukGraph mygraph (A->Graph(), 0, 0);
IC = Teuchos::rcp( new Ifpack_CrsRick(*A, mygraph) );
IC->SetAbsoluteThreshold(0.00123);
IC->SetRelativeThreshold(0.9876);
// Init values from A
IC->InitValues(*A);
// compute the factors
IC->Factor();
// and now estimate the condition number
IC->Condest(false,Condest);
if( Comm.MyPID() == 0 ) {
cout << "Condition number estimate (level-of-fill = "
<< LevelFill << ") = " << Condest << endl;
}
// Define label for printing out during the solve phase
std::string label = "Ifpack_CrsRick Preconditioner: LevelFill = " + toString(LevelFill) +
" Overlap = 0";
IC->SetLabel(label.c_str());
// Here we create an AztecOO object
LHS->PutScalar(0.0);
AztecOO solver;
solver.SetUserMatrix(&*A);
solver.SetLHS(&*LHS);
solver.SetRHS(&*RHS);
solver.SetAztecOption(AZ_solver,AZ_cg);
solver.SetPrecOperator(&*IC);
solver.SetAztecOption(AZ_output, 16);
solver.Iterate(maxIter, tol);
int RickIters = solver.NumIters();
//cout << "Ifpack_Rick iterations: " << RickIters << endl;
// Compare to no preconditioning
if (RickIters > Iters/2)
IFPACK_CHK_ERR(-1);
#endif
//////////////////////////////////////////////////////
// Same test with Ifpack_IC
// This is Crout threshold Cholesky, so different than IC(0)
Ifpack Factory;
Teuchos::RefCountPtr<Ifpack_Preconditioner> PrecIC = Teuchos::rcp( Factory.Create("IC", &*A) );
Teuchos::ParameterList List;
//List.get("fact: ict level-of-fill", 2.);
//List.get("fact: drop tolerance", 0.3333);
//List.get("fact: absolute threshold", 0.00123);
//List.get("fact: relative threshold", 0.9876);
//List.get("fact: relaxation value", 0.0);
IFPACK_CHK_ERR(PrecIC->SetParameters(List));
IFPACK_CHK_ERR(PrecIC->Compute());
// Here we create an AztecOO object
LHS->PutScalar(0.0);
//AztecOO solver;
solver.SetUserMatrix(&*A);
solver.SetLHS(&*LHS);
solver.SetRHS(&*RHS);
solver.SetAztecOption(AZ_solver,AZ_cg);
solver.SetPrecOperator(&*PrecIC);
solver.SetAztecOption(AZ_output, 16);
solver.Iterate(maxIter, tol);
int ICIters = solver.NumIters();
//cout << "Ifpack_IC iterations: " << ICIters << endl;
// Compare to no preconditioning
if (ICIters > Iters/2)
IFPACK_CHK_ERR(-1);
#if 0
//////////////////////////////////////////////////////
// Same test with Ifpack_ICT
// This is another threshold Cholesky
Teuchos::RefCountPtr<Ifpack_Preconditioner> PrecICT = Teuchos::rcp( Factory.Create("ICT", &*A) );
//Teuchos::ParameterList List;
//List.get("fact: level-of-fill", 2);
//List.get("fact: drop tolerance", 0.3333);
//List.get("fact: absolute threshold", 0.00123);
//List.get("fact: relative threshold", 0.9876);
//List.get("fact: relaxation value", 0.0);
IFPACK_CHK_ERR(PrecICT->SetParameters(List));
IFPACK_CHK_ERR(PrecICT->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_cg);
solver.SetPrecOperator(&*PrecICT);
solver.SetAztecOption(AZ_output, 16);
solver.Iterate(maxIter, tol);
int ICTIters = solver.NumIters();
//cout << "Ifpack_ICT iterations: " << ICTIters << endl;
// Compare to no preconditioning
if (ICTIters > Iters/2)
IFPACK_CHK_ERR(-1);
#endif
#ifdef HAVE_MPI
MPI_Finalize() ;
#endif
return(EXIT_SUCCESS);
}