mathcomp.la
Class Matrix

java.lang.Object
  mathcomp.la.Matrix

Direct Known Subclasses:

MapMatrix

public abstract class Matrix
extends java.lang.Object

A quadratic matrix based on an index. To access the elements use the methods get(Object i, Object j) and set(Object i, Object j, double value). The Matrix is designed for sparse handling. So use the relevantIndices(Object row) for handling the matrix.

Author:

pht

Constructor Summary

Matrix()

Method Summary

void	add(java.lang.Object i, java.lang.Object j, double x) Performs this(i,j) = this(i.j) + x.
abstract Matrix	copy() Creates a copy of this matrix.
abstract double	get(java.lang.Object i, java.lang.Object j) Returns value at (i,j).
abstract Index	getIndex()
double	map(Vector v, java.lang.Object row)
Vector	map(Vector v, Vector ret) Performs ret := this*v, i.e.
java.util.Iterator	relevantIndices(java.lang.Object row) Returns Iterator, that traverses all indices of nonnull elements in the row row.
int	relevantIndicesNum(java.lang.Object row) Returns the number of nonnull elements in row row.
abstract void	set(java.lang.Object i, java.lang.Object j, double x) Sets value at (i,j) to x.
Matrix	transpose(Matrix ret) Performs ret := this^T, i.e.

Methods inherited from class java.lang.Object

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

Constructor Detail

Matrix

public Matrix()

Method Detail

getIndex

public abstract Index getIndex()

get

public abstract double get(java.lang.Object i,
                           java.lang.Object j)

Returns value at (i,j).

Parameters:

i - index of the row

j - index of the column

Returns:

value at (i,j)

set

public abstract void set(java.lang.Object i,
                         java.lang.Object j,
                         double x)

Sets value at (i,j) to x.

Parameters:

i - index of the row

j - index of the column

x - value to set at (i,j)

copy

public abstract Matrix copy()

Creates a copy of this matrix.

Returns:

a copy of this matrix

relevantIndices

public java.util.Iterator relevantIndices(java.lang.Object row)

Returns Iterator, that traverses all indices of nonnull elements in the row row.

Parameters:

row - the index of the row

Returns:

Iterator, that traverses all indices of nonnull elements in the row row

relevantIndicesNum

public int relevantIndicesNum(java.lang.Object row)

Returns the number of nonnull elements in row row.

Parameters:

row - the index of the row

Returns:

the number of nonnull elements in row row

map

public double map(Vector v,
                  java.lang.Object row)

Parameters:

v - the vector to map

row - index of the component we want to calculate

Returns:

scalar product of v and the row row.

map

public Vector map(Vector v,
                  Vector ret)

Performs ret := this*v, i.e. matrix-vector multiplication of this matrix and v, stored the result in ret, which will be returned.

Parameters:

v - the vector to map

ret - vector in which will be stored the result of the mapping.

Returns:

the matrix-vector multiplication of this matrix and v. ret will be returned

add

public void add(java.lang.Object i,
                java.lang.Object j,
                double x)

Performs this(i,j) = this(i.j) + x.

Parameters:

i - index of the row

j - index of the column

x - the value to add

transpose

public Matrix transpose(Matrix ret)

Performs ret := this^T, i.e. this transposed and stores the result in ret, which will be returned.

Parameters:

ret - temporary Matrix

Returns:

this transposed. ret will be returned