no.uib.cipr.matrix.sparse
Class QMR

java.lang.Object
  extended by no.uib.cipr.matrix.sparse.AbstractIterativeSolver
      extended by no.uib.cipr.matrix.sparse.QMR
All Implemented Interfaces:
IterativeSolver

public class QMR
extends AbstractIterativeSolver

Quasi-Minimal Residual method. QMR solves the unsymmetric linear system Ax = b using the Quasi-Minimal Residual method. QMR uses two preconditioners, and by default these are the same preconditioner.


Field Summary
 
Fields inherited from class no.uib.cipr.matrix.sparse.AbstractIterativeSolver
iter, M
 
Constructor Summary
QMR(Vector template)
          Constructor for QMR.
QMR(Vector template, Preconditioner M1, Preconditioner M2)
          Constructor for QMR.
 
Method Summary
 void setPreconditioner(Preconditioner M)
          Sets preconditioner
 Vector solve(Matrix A, Vector b, Vector x)
          Solves the given problem, writing result into the vector.
 
Methods inherited from class no.uib.cipr.matrix.sparse.AbstractIterativeSolver
checkSizes, getIterationMonitor, getPreconditioner, setIterationMonitor
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

QMR

public QMR(Vector template)
Constructor for QMR. Uses the given vector as template for creating scratch vectors. Typically, the solution or the right hand side vector can be passed, and the template is not modified

Parameters:
template - Vector to use as template for the work vectors needed in the solution process

QMR

public QMR(Vector template,
           Preconditioner M1,
           Preconditioner M2)
Constructor for QMR. Uses the given vector as template for creating scratch vectors. Typically, the solution or the right hand side vector can be passed, and the template is not modified. Allows setting different right and left preconditioners

Parameters:
template - Vector to use as template for the work vectors needed in the solution process
M1 - Left preconditioner
M2 - Right preconditioner
Method Detail

solve

public Vector solve(Matrix A,
                    Vector b,
                    Vector x)
             throws IterativeSolverNotConvergedException
Description copied from interface: IterativeSolver
Solves the given problem, writing result into the vector.

Parameters:
A - Matrix of the problem
b - Right hand side
x - Solution is stored here. Also used as initial guess
Returns:
The solution vector x
Throws:
IterativeSolverNotConvergedException

setPreconditioner

public void setPreconditioner(Preconditioner M)
Description copied from interface: IterativeSolver
Sets preconditioner

Specified by:
setPreconditioner in interface IterativeSolver
Overrides:
setPreconditioner in class AbstractIterativeSolver
Parameters:
M - Preconditioner to use