Class BandMatrix

java.lang.Object
  BandMatrix

public class BandMatrix

extends java.lang.Object

BandMatrix - Linear algebra package for band matrices

Field Summary

(package private) int	c
(package private) double[]	d
(package private) double	det
(package private) int	diagos
(package private) boolean	isDecomposed
(package private) int	l
(package private) int	lines
(package private) double[][]	m
(package private) int	n
(package private) int	r

Constructor Summary

BandMatrix(int diagos, int lines)
Constructor

Method Summary

double[]	dot(double[] v) Matrix times vector
double	get(int j, int i) Retrieve value of matrix elements
double	getD(int i)
double	getL(int i)
double	getR(int i)
boolean	isEqual(double[] sol, double[] ini, double precision) Decide whether two vectors are equal to a certain degree of precision
void	set(int i, int j, double v) Store matrix elements
void	setD(int i, double v)
void	setL(int i, double v)
void	setR(int i, double v)
double[]	solve3(double[] rhs) Direct LU solver for 3-banded matrix with multiple RHS and BC The matrix is decomposed once only for the first rhs vector Periodic boundary conditions are taken care of by the upper-left lower-right most matrix elements
double[]	ssor3(double[] rhs, double[] ini) Projected Symmetric Over Relaxation for 3-banded matrix Periodic boundary conditions are taken care of by the upper-left lower-right most matrix elements
double[]	ssor3(double[] rhs, double[] ini, double[] min, double[] max, double precision, double w, int maxIterations) Projected Symmetric Over Relaxation for 3-banded matrix Periodic boundary conditions are taken care of by the upper-left lower-right most matrix elements

Methods inherited from class java.lang.Object

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

Field Detail

m

double[][] m

d

double[] d

det

double det

diagos

int diagos

lines

int lines

n

int n

isDecomposed

boolean isDecomposed

l

int l

c

int c

r

int r

Constructor Detail

BandMatrix

public BandMatrix(int diagos,
                  int lines)

Constructor

Method Detail

set

public void set(int i,
                int j,
                double v)

Store matrix elements

setL

public void setL(int i,
                 double v)

setD

public void setD(int i,
                 double v)

setR

public void setR(int i,
                 double v)

get

public double get(int j,
                  int i)

Retrieve value of matrix elements

getL

public double getL(int i)

getD

public double getD(int i)

getR

public double getR(int i)

dot

public double[] dot(double[] v)

Matrix times vector

solve3

public double[] solve3(double[] rhs)

Direct LU solver for 3-banded matrix with multiple RHS and BC The matrix is decomposed once only for the first rhs vector Periodic boundary conditions are taken care of by the upper-left lower-right most matrix elements

Parameters:

rhs - Right hand side vector

Returns:

Solution of the linear system

ssor3

public double[] ssor3(double[] rhs,
                      double[] ini,
                      double[] min,
                      double[] max,
                      double precision,
                      double w,
                      int maxIterations)

Projected Symmetric Over Relaxation for 3-banded matrix Periodic boundary conditions are taken care of by the upper-left lower-right most matrix elements

Parameters:

rhs - Right hand side vector

ini - Initial iterate

min - Lower limit for obstacle problems

max - Upper limit for obstacle problems

precision - Relative precision required

w - Relaxation parameter to be chosen within [0;2]

maxIterations - Maximum number of iterations

Returns:

Solution of the linear system

ssor3

public double[] ssor3(double[] rhs,
                      double[] ini)

Projected Symmetric Over Relaxation for 3-banded matrix Periodic boundary conditions are taken care of by the upper-left lower-right most matrix elements

Parameters:

rhs - Right hand side vector

ini - Initial iterate

Returns:

Solution of the linear system

isEqual

public boolean isEqual(double[] sol,
                       double[] ini,
                       double precision)

Decide whether two vectors are equal to a certain degree of precision

Parameters:

sol - First vector

ini - Second vector

precision - Absolute precision

Returns:

true is both vectors are equal