org.jutil.math.matrix
Class AbstractSolver

java.lang.Object
  |
  +--org.jutil.math.matrix.AbstractSolver

Direct Known Subclasses:

LULinSolver, QRLeastSquaresSolver, QRLinSolver

public abstract class AbstractSolver

extends java.lang.Object

A helper class for classes that solve systems of equations using matrices. That often involves solve a triangular system at the end.

Version:

$Revision: 1.2 $

Author:

Marko van Dooren

Constructor Summary

AbstractSolver()

Method Summary

Column	backSubstitute(Matrix R, Column b) public behavior pre R != null; pre b != null; pre R.isSquare(); pre R.isUpperTriangular; pre b.size() == R.getNbRows(); pre (* R is nonsingular *); post (* R.times(\result).equals(b) *);
Column	forwardSubstitute(Matrix R, Column b) public behavior pre L!= null; pre b != null; pre L.isSquare(); pre L.isLowerTriangular; pre b.size() == L.getNbRows(); pre (* L is nonsingular *); post (* L.times(\result).equals(b) *);

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractSolver

public AbstractSolver()

Method Detail

backSubstitute

public Column backSubstitute(Matrix R,
                             Column b)

public behavior

pre R != null;
pre b != null;
pre R.isSquare();
pre R.isUpperTriangular;
pre b.size() == R.getNbRows();
pre (* R is nonsingular *);

post (* R.times(\result).equals(b) *);

Solve the uppertriangular linear system of equations defined by R * x = b

Parameters:

R - The uppertriangular matrix containing the coefficients of the equations.

b - A column containing the right-hand sides of the equations.

forwardSubstitute

public Column forwardSubstitute(Matrix R,
                                Column b)

public behavior

pre L!= null;
pre b != null;
pre L.isSquare();
pre L.isLowerTriangular;
pre b.size() == L.getNbRows();
pre (* L is nonsingular *);

post (* L.times(\result).equals(b) *);

Solve the lowertriangular linear system of equations defined by L * x = b

Parameters:

L - The lowertriangular matrix containing the coefficients of the equations.

b - A column containing the right-hand sides of the equations.