no.uib.cipr.matrix.sparse
Class DiagonalPreconditioner

java.lang.Object
  no.uib.cipr.matrix.sparse.DiagonalPreconditioner

All Implemented Interfaces:

Preconditioner

public class DiagonalPreconditioner
extends java.lang.Object
implements Preconditioner

Diagonal preconditioner. Uses the inverse of the diagonal as preconditioner

Constructor Summary

DiagonalPreconditioner(int n)
Constructor for DiagonalPreconditioner

Method Summary

Vector	apply(Vector b, Vector x) Solves the approximate problem with the given right hand side.
void	setMatrix(Matrix A) Sets the operator matrix for the preconditioner.
Vector	transApply(Vector b, Vector x) Solves the approximate transpose problem with the given right hand side.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DiagonalPreconditioner

public DiagonalPreconditioner(int n)

Constructor for DiagonalPreconditioner

Parameters:

n - Problem size (number of rows)

Method Detail

apply

public Vector apply(Vector b,
                    Vector x)

Description copied from interface: Preconditioner

Solves the approximate problem with the given right hand side. Result is stored in given solution vector

Specified by:

apply in interface Preconditioner

Parameters:

b - Right hand side of problem

x - Result is stored here

Returns:

x

transApply

public Vector transApply(Vector b,
                         Vector x)

Description copied from interface: Preconditioner

Solves the approximate transpose problem with the given right hand side. Result is stored in given solution vector

Specified by:

transApply in interface Preconditioner

Parameters:

b - Right hand side of problem

x - Result is stored here

Returns:

x

setMatrix

public void setMatrix(Matrix A)

Description copied from interface: Preconditioner

Sets the operator matrix for the preconditioner. This method must be called before a preconditioner is used by an iterative solver

Specified by:

setMatrix in interface Preconditioner

Parameters:

A - Matrix to setup the preconditioner for. Not modified