Package pulse.problem.schemes

Class TridiagonalMatrixAlgorithm

java.lang.Object

pulse.problem.schemes.TridiagonalMatrixAlgorithm

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

BlockMatrixAlgorithm

public class TridiagonalMatrixAlgorithm
extends Object
implements Serializable

Implements the tridiagonal matrix algorithm (Thomas algorithms) for solving systems of linear equations. Applicable to such systems where the forming matrix has a tridiagonal form: A_i*x_i-1 - B_i x_i + C_i x_i+1 = -F_i.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
TridiagonalMatrixAlgorithm(Grid grid)

Method Summary

Modifier and Type	Method	Description
double	beta(double f, double phi, int i)
void	evaluateAlpha()	Calculates the alpha coefficients as part of the tridiagonal matrix algorithm.
void	evaluateBeta(double[] U)
void	evaluateBeta(double[] U, int start, int endExclusive)	Calculates the beta coefficients as part of the tridiagonal matrix algorithm.
double[]	getAlpha()
double[]	getBeta()
protected double	getCoefA()
protected double	getCoefB()
protected double	getCoefC()
int	getGridPoints()
double	getGridStep()
double	getTimeStep()
double	phi(int i)
void	setAlpha(int i, double alpha)
void	setBeta(int i, double beta)
void	setCoefA(double a)
void	setCoefB(double b)
void	setCoefC(double c)
void	sweep(double[] V)	Calculates the solution V using the tridiagonal matrix algorithm.

Methods inherited from class java.lang.Object

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

Constructor Detail

TridiagonalMatrixAlgorithm

public TridiagonalMatrixAlgorithm(Grid grid)

Method Detail

sweep

public void sweep(double[] V)

Calculates the solution V using the tridiagonal matrix algorithm. This performs a backwards sweep from N - 1 to 0 where N is the grid density value. The coefficients alpha and beta should have been precalculated

Parameters:

V - the array containing the Nth value previously calculated from the respective boundary condition

evaluateAlpha

public void evaluateAlpha()

Calculates the alpha coefficients as part of the tridiagonal matrix algorithm.

evaluateBeta

public void evaluateBeta(double[] U)

evaluateBeta

public void evaluateBeta(double[] U,
                         int start,
                         int endExclusive)

Calculates the beta coefficients as part of the tridiagonal matrix algorithm.

Parameters:

U -

start -

endExclusive -

beta

public double beta(double f,
                   double phi,
                   int i)

phi

public double phi(int i)

setAlpha

public void setAlpha(int i,
                     double alpha)

setBeta

public void setBeta(int i,
                    double beta)

getAlpha

public double[] getAlpha()

getBeta

public double[] getBeta()

setCoefA

public void setCoefA(double a)

setCoefB

public void setCoefB(double b)

setCoefC

public void setCoefC(double c)

getCoefA

protected double getCoefA()

getCoefB

protected double getCoefB()

getCoefC

protected double getCoefC()

getTimeStep

public final double getTimeStep()

getGridPoints

public final int getGridPoints()

getGridStep

public final double getGridStep()