org.spaceroots.mantissa.linalg

Class SymetricalMatrix

java.lang.Object

org.spaceroots.mantissa.linalg.Matrix

org.spaceroots.mantissa.linalg.SquareMatrix

org.spaceroots.mantissa.linalg.GeneralSquareMatrix

org.spaceroots.mantissa.linalg.SymetricalMatrix

All Implemented Interfaces:

java.io.Serializable

public class SymetricalMatrix
extends GeneralSquareMatrix

This class implements symetrical matrices of linear algebra.

Version:

$Id: SymetricalMatrix.java 1709 2006-12-03 21:16:50Z luc $

Author:

L. Maisonobe

See Also:

Serialized Form

Field Summary

Fields inherited from class org.spaceroots.mantissa.linalg.Matrix

columns, data, rows

Constructor Summary

Constructors

Constructor and Description
SymetricalMatrix(double w, double[] a) Build the symetrical matrix resulting from the product w.A.At.
SymetricalMatrix(int order) Simple constructor.
SymetricalMatrix(int order, double[] data) Simple constructor.
SymetricalMatrix(SymetricalMatrix s) Copy constructor.

Method Summary

Modifier and Type	Method and Description
Matrix	duplicate() Polymorphic copy operator.
void	selfAdd(SymetricalMatrix s) Add a matrix to the instance.
void	selfAddWAAt(double w, double[] a) Add the symetrical matrix resulting from the product w.A.At to the instance.
void	selfSub(SymetricalMatrix s) Substract a matrix from the instance.
void	setElement(int i, int j, double value) Set a matrix element.
void	setElementAndSymetricalElement(int i, int j, double value) Set both a matrix element and its symetrical element.

Methods inherited from class org.spaceroots.mantissa.linalg.GeneralSquareMatrix

getDeterminant, getRangeForColumn, getRangeForRow, selfAdd, selfSub, solve

Methods inherited from class org.spaceroots.mantissa.linalg.SquareMatrix

getInverse, solve

Methods inherited from class org.spaceroots.mantissa.linalg.Matrix

add, getColumns, getElement, getRows, getTranspose, mul, mul, selfMul, sub, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

SymetricalMatrix

public SymetricalMatrix(int order)

Simple constructor. This constructor builds a symetrical matrix of specified order, all elements beeing zeros.

Parameters:

order - order of the matrix

SymetricalMatrix

public SymetricalMatrix(int order,
                        double[] data)

Simple constructor. Build a matrix with specified elements.

Parameters:

order - order of the matrix

data - table of the matrix elements (stored row after row)

SymetricalMatrix

public SymetricalMatrix(SymetricalMatrix s)

Copy constructor.

Parameters:

s - square matrix to copy

SymetricalMatrix

public SymetricalMatrix(double w,
                        double[] a)

Build the symetrical matrix resulting from the product w.A.At.

Parameters:

w - multiplicative factor (weight)

a - base vector used to compute the symetrical contribution

Method Detail

duplicate

public Matrix duplicate()

Description copied from class: Matrix

Polymorphic copy operator. This method build a new object of the same type of the instance. It is somewhat similar to the Object.clone() method, except that it has public access, it doesn't throw any specific exception and it returns a Matrix.

Overrides:

duplicate in class GeneralSquareMatrix

See Also:

Object.clone()

setElement

public void setElement(int i,
                       int j,
                       double value)

Set a matrix element. On symetrical matrices, setting separately elements outside of the diagonal is forbidden, so this method throws an ArrayIndexOutOfBoundsException in this case. The setElementAndSymetricalElement(int, int, double) can be used to set both elements simultaneously.

Overrides:

setElement in class GeneralSquareMatrix

Parameters:

i - row index, from 0 to rows - 1

j - column index, from 0 to cols - 1

value - value of the element

Throws:

java.lang.ArrayIndexOutOfBoundsException - if the indices are wrong

See Also:

setElementAndSymetricalElement(int, int, double), Matrix.getElement(int, int)

setElementAndSymetricalElement

public void setElementAndSymetricalElement(int i,
                                           int j,
                                           double value)

Set both a matrix element and its symetrical element.

Parameters:

i - row index of first element (column index of second element), from 0 to order - 1

j - column index of first element (row index of second element), from 0 to order - 1

value - value of the elements

Throws:

java.lang.ArrayIndexOutOfBoundsException - if the indices are wrong

See Also:

setElement(int, int, double), Matrix.getElement(int, int)

selfAdd

public void selfAdd(SymetricalMatrix s)

Add a matrix to the instance. This method adds a matrix to the instance. It does modify the instance.

Parameters:

s - symetrical matrix to add

Throws:

java.lang.IllegalArgumentException - if there is a dimension mismatch

selfSub

public void selfSub(SymetricalMatrix s)

Substract a matrix from the instance. This method substracts a matrix from the instance. It does modify the instance.

Parameters:

s - symetrical matrix to substract

Throws:

java.lang.IllegalArgumentException - if there is a dimension mismatch

selfAddWAAt

public void selfAddWAAt(double w,
                        double[] a)

Add the symetrical matrix resulting from the product w.A.At to the instance. This method can be used to build progressively the matrices of least square problems. The instance is modified.

Parameters:

w - multiplicative factor (weight)

a - base vector used to compute the symetrical contribution

Throws:

java.lang.IllegalArgumentException - if there is a dimension mismatch