Opus5
Class SparseMatrixAsArray

java.lang.Object
  |
  +--Opus5.SparseMatrixAsArray

All Implemented Interfaces:

Matrix, SparseMatrix

public class SparseMatrixAsArray

extends java.lang.Object

implements SparseMatrix

Sparse matrix implemented using arrays.

Version:

$Id: SparseMatrixAsArray.java,v 3.2 1998/07/28 03:02:23 brpreiss Exp $

Author:

Bruno R. Preiss, P.Eng.

Field Summary

protected int[][]	columns The column numbers corresponding to the non-zero entries.
protected int	fill The maximum number of non-zero entries in any row of the sparse matrix.
protected int	numberOfColumns The number of columns.
protected int	numberOfRows The number of rows.
protected double[][]	values The non-zero matrix entries.

Fields inherited from interface Opus5.SparseMatrix

copyright

Constructor Summary

SparseMatrixAsArray(int numberOfRows, int numberOfColumns, int fill)
Construct a SparseMatrixAsArray with the specified dimensions and row fill.

Method Summary

protected int	findPosition(int i, int j) Finds the position of the (i,j)th matrix entry.
double	get(int i, int j) Returns the value in this matrix at the specified position.
Matrix	plus(Matrix mat) Returns the sum of this matrix and the specified matrix.
void	put(int i, int j, double datum) Stores the specified value in this matrix at the specified position.
void	putZero(int i, int j) Stores a zero in this matrix at the specified position.
Matrix	times(Matrix mat) Returns the product of this matrix and the specified matrix.
Matrix	transpose() Returns the transpose of this matrix.

Methods inherited from class java.lang.Object

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

Field Detail

numberOfColumns

protected int numberOfColumns

The number of columns.

numberOfRows

protected int numberOfRows

The number of rows.

fill

protected int fill

The maximum number of non-zero entries in any row of the sparse matrix.

values

protected double[][] values

The non-zero matrix entries.

columns

protected int[][] columns

The column numbers corresponding to the non-zero entries.

Constructor Detail

SparseMatrixAsArray

public SparseMatrixAsArray(int numberOfRows,
                           int numberOfColumns,
                           int fill)

Construct a SparseMatrixAsArray with the specified dimensions and row fill.

Parameters:

numberOfRows - The number of rows.

numberOfColumns - The number of columns.

fill - The maximum number of non-zero entries in any row.

Method Detail

findPosition

protected int findPosition(int i,
                           int j)

Finds the position of the (i,j)th matrix entry.

Parameters:

i - The row number.

j - The column number.

Returns:

The position of the (i,j)th matrix entry; -1 if the matrix entry is zero.

get

public double get(int i,
                  int j)

Returns the value in this matrix at the specified position.

Specified by:

get in interface Matrix

Parameters:

i - The row number.

j - The column number.

Returns:

The value in this matrix at the specified position.

put

public void put(int i,
                int j,
                double datum)

Stores the specified value in this matrix at the specified position.

Specified by:

put in interface Matrix

Parameters:

i - The row number.

j - The column number.

datum - The value to be stored.

putZero

public void putZero(int i,
                    int j)

Stores a zero in this matrix at the specified position.

Specified by:

putZero in interface SparseMatrix

Parameters:

i - The row number.

j - The column number.

transpose

public Matrix transpose()

Returns the transpose of this matrix. This method is not implemented.

Specified by:

transpose in interface Matrix

Returns:

The transpose of this matrix.

Throws:

MethodNotImplemented - Always.

times

public Matrix times(Matrix mat)

Returns the product of this matrix and the specified matrix. This method is not implemented.

Specified by:

times in interface Matrix

Parameters:

The - specified matrix.

Returns:

The product of this matrix and the specified matrix

Throws:

MethodNotImplemented - Always.

plus

public Matrix plus(Matrix mat)

Returns the sum of this matrix and the specified matrix. This method is not implemented.

Specified by:

plus in interface Matrix

Parameters:

The - specified matrix.

Returns:

The sum of this matrix and the specified matrix

Throws:

MethodNotImplemented - Always.