Use LOBPCG with Epetra, for a generalized eigenvalue problem.
Use LOBPCG with Epetra, for a generalized eigenvalue problem.
This example computes the eigenvalues of largest magnitude of an generalized eigenvalue problem, using Anasazi's implementation of the LOBPCG method, with Epetra linear algebra.
#include "Epetra_CrsMatrix.h"
#include "Teuchos_CommandLineProcessor.hpp"
#include "Teuchos_StandardCatchMacros.hpp"
#ifdef HAVE_MPI
#include "Epetra_MpiComm.h"
#include <mpi.h>
#else
#include "Epetra_SerialComm.h"
#endif
#include "Epetra_Map.h"
#include "ModeLaplace2DQ2.h"
int main(int argc, char *argv[]) {
#ifdef HAVE_MPI
MPI_Init(&argc,&argv);
#endif
bool success = false;
try {
#ifdef HAVE_MPI
Epetra_MpiComm Comm(MPI_COMM_WORLD);
#else
Epetra_SerialComm Comm;
#endif
printer.
stream(Errors) << Anasazi_Version() << std::endl << std::endl;
std::string which("SM");
Teuchos::CommandLineProcessor cmdp(false,true);
cmdp.setOption("sort",&which,"Targetted eigenvalues (SM or LM).");
if (cmdp.parse(argc,argv) != Teuchos::CommandLineProcessor::PARSE_SUCCESSFUL) {
throw -1;
}
typedef Epetra_MultiVector MV;
typedef Epetra_Operator OP;
const int space_dim = 2;
std::vector<double> brick_dim( space_dim );
brick_dim[0] = 1.0;
brick_dim[1] = 1.0;
std::vector<int> elements( space_dim );
elements[0] = 10;
elements[1] = 10;
Teuchos::RCP<ModalProblem> testCase =
Teuchos::rcp( new ModeLaplace2DQ2(Comm, brick_dim[0], elements[0], brick_dim[1], elements[1]) );
Teuchos::RCP<Epetra_CrsMatrix> K = Teuchos::rcp( const_cast<Epetra_CrsMatrix *>(testCase->getStiffness()), false );
Teuchos::RCP<Epetra_CrsMatrix> M = Teuchos::rcp( const_cast<Epetra_CrsMatrix *>(testCase->getMass()), false );
int nev = 10;
int blockSize = 5;
int maxIters = 500;
double tol = 1.0e-8;
Teuchos::RCP<Epetra_MultiVector> ivec = Teuchos::rcp( new Epetra_MultiVector(K->OperatorDomainMap(), blockSize) );
ivec->Random();
Teuchos::RCP<BasicEigenproblem<double, MV, OP> > MyProblem =
MyProblem->setHermitian(true);
MyProblem->setNEV( nev );
bool boolret = MyProblem->setProblem();
if (boolret != true) {
printer.
print(Errors,
"Anasazi::BasicEigenproblem::setProblem() returned an error.\n");
throw -1;
}
Teuchos::ParameterList MyPL;
MyPL.set( "Which", which );
MyPL.set( "Block Size", blockSize );
MyPL.set( "Maximum Iterations", maxIters );
MyPL.set( "Convergence Tolerance", tol );
MyPL.set( "Full Ortho", true );
MyPL.set( "Use Locking", true );
MyPL.set( "Verbosity", verbosity );
std::vector<Value<double> > evals = sol.
Evals;
Teuchos::RCP<MV> evecs = sol.
Evecs;
std::vector<double> normR(sol.
numVecs);
Epetra_MultiVector Kvec( K->OperatorDomainMap(), evecs->NumVectors() );
Epetra_MultiVector Mvec( M->OperatorDomainMap(), evecs->NumVectors() );
T.putScalar(0.0);
for (
int i=0; i<sol.
numVecs; i++) {
T(i,i) = evals[i].realpart;
}
K->Apply( *evecs, Kvec );
M->Apply( *evecs, Mvec );
MVT::MvTimesMatAddMv( -1.0, Mvec, T, 1.0, Kvec );
MVT::MvNorm( Kvec, normR );
}
std::ostringstream os;
os.setf(std::ios_base::right, std::ios_base::adjustfield);
os<<"Solver manager returned " << (returnCode == Converged ? "converged." : "unconverged.") << std::endl;
os<<std::endl;
os<<"------------------------------------------------------"<<std::endl;
os<<std::setw(16)<<"Eigenvalue"
<<std::setw(18)<<"Direct Residual"
<<std::endl;
os<<"------------------------------------------------------"<<std::endl;
for (
int i=0; i<sol.
numVecs; i++) {
os<<std::setw(16)<<evals[i].realpart
<<std::setw(18)<<normR[i]/evals[i].realpart
<<std::endl;
}
os<<"------------------------------------------------------"<<std::endl;
printer.
print(Errors,os.str());
success = true;
}
TEUCHOS_STANDARD_CATCH_STATEMENTS(true, std::cerr, success);
#ifdef HAVE_MPI
MPI_Finalize();
#endif
return ( success ? EXIT_SUCCESS : EXIT_FAILURE );
}
Basic implementation of the Anasazi::Eigenproblem class.
Basic output manager for sending information of select verbosity levels to the appropriate output str...
Anasazi header file which uses auto-configuration information to include necessary C++ headers.
Declarations of Anasazi multi-vector and operator classes using Epetra_MultiVector and Epetra_Operato...
The Anasazi::LOBPCGSolMgr provides a powerful solver manager for the LOBPCG eigensolver.
This provides a basic implementation for defining standard or generalized eigenvalue problems.
Anasazi's basic output manager for sending information of select verbosity levels to the appropriate ...
User interface for the LOBPCG eigensolver.
ReturnType solve()
This method performs possibly repeated calls to the underlying eigensolver's iterate() routine until ...
Traits class which defines basic operations on multivectors.
virtual Teuchos::FancyOStream & stream(MsgType type)
Create a stream for outputting to.
virtual void print(MsgType type, const std::string output)
Send output to the output manager.
Namespace Anasazi contains the classes, structs, enums and utilities used by the Anasazi package.
ReturnType
Enumerated type used to pass back information from a solver manager.
Struct for storing an eigenproblem solution.
Teuchos::RCP< MV > Evecs
The computed eigenvectors.
int numVecs
The number of computed eigenpairs.
std::vector< Value< ScalarType > > Evals
The computed eigenvalues.