org.jmatrices.dbl
Interface Matrix

All Superinterfaces:

java.io.Serializable

public interface Matrix

extends java.io.Serializable

Matrix represents a structurally immutable matrix of numbers(double) with index begining at 1.

The only way to change the elements in a matrix is through set(int, int, double)

A good convention to follow is to use row=1;row<=rows();row++(col=1;col<=cols();coll++) as indices while looping over matrix elements.

And use the normal i,j,k etc. to iterate over arrays!

Author: purangp

Date: 07.03.2004 Time: 15:52:02

Method Summary

int	cols() Gets the number of columns in the matrix counts from 1
double[][]	get() Gets a copy of the elements as a 2D array.
double	get(int row, int col) Gets the value of the element at the given row and column
Matrix	getColumn(int col) Gets the entire column as a matrix
Matrix	getRow(int row) Gets the entire row as a matrix
Matrix	getSubMatrix(int[] r, int[] c) Get a submatrix.
Matrix	getSubMatrix(int[] r, int colI, int colF) Get a submatrix.
Matrix	getSubMatrix(int rowI, int rowF, int[] c) Get a submatrix.
Matrix	getSubMatrix(int rowI, int colI, int rowF, int colF) Get a submatrix.
int	rows() Gets the number of rows in the matrix Counts from 1
void	set(int row, int col, double value) Sets an element at the given position to a new value

Method Detail

rows

public int rows()

Gets the number of rows in the matrix

Counts from 1

Returns:

number of rows in the matrix

cols

public int cols()

Gets the number of columns in the matrix

counts from 1

Returns:

number of columns in the matrix

set

public void set(int row,
                int col,
                double value)

Sets an element at the given position to a new value

Parameters:

row - row in which the element occurs

col - column in which the element occurs

value - the new value to be set

get

public double get(int row,
                  int col)

Gets the value of the element at the given row and column

Parameters:

row - row in which the element occurs

col - column in which the element occurs

Returns:

value of the element

getRow

public Matrix getRow(int row)

Gets the entire row as a matrix

Parameters:

row - row asked for

Returns:

Matrix containing the row

getColumn

public Matrix getColumn(int col)

Gets the entire column as a matrix

Parameters:

col - column asked for

Returns:

Matrix containing the column

get

public double[][] get()

Gets a copy of the elements as a 2D array.

Copy signifies the fact that any modifications made on the copy will not affect the Source matrix!

Returns:

copy of all elements as a 2D array

getSubMatrix

public Matrix getSubMatrix(int rowI,
                           int colI,
                           int rowF,
                           int colF)

Get a submatrix.

Parameters:

rowI - Initial row index

colI - Initial column index

rowF - Final row index

colF - Final column index

Returns:

A(rowI:rowF,colI:colF)

Throws:

java.lang.ArrayIndexOutOfBoundsException - Submatrix indices

getSubMatrix

public Matrix getSubMatrix(int[] r,
                           int[] c)

Get a submatrix.

Parameters:

r - Array of row indices.

c - Array of column indices.

Returns:

A(r(:),c(:))

Throws:

java.lang.ArrayIndexOutOfBoundsException - Submatrix indices

getSubMatrix

public Matrix getSubMatrix(int rowI,
                           int rowF,
                           int[] c)

Get a submatrix.

Parameters:

rowI - Initial row index

rowF - Final row index

c - Array of column indices.

Returns:

A(i0:i1,c(:))

Throws:

java.lang.ArrayIndexOutOfBoundsException - Submatrix indices

getSubMatrix

public Matrix getSubMatrix(int[] r,
                           int colI,
                           int colF)

Get a submatrix.

Parameters:

r - Array of row indices.

colI - Initial column index

colF - Final column index

Returns:

A(r(:),j0:j1)

Throws:

java.lang.ArrayIndexOutOfBoundsException - Submatrix indices