infomat.vectorspace.weighting
Class TFIDFWeighter

java.lang.Object
  infomat.vectorspace.weighting.Weighter
      infomat.vectorspace.weighting.TFIDFWeighter

All Implemented Interfaces:

HasProperties

public class TFIDFWeighter
extends Weighter

A class for weighting of a IMatrix. Currently works in a specific direction! Considers rows to be objects (texts) and columns to be features (words).

Field Summary

Fields inherited from class infomat.vectorspace.weighting.Weighter

properties

Constructor Summary

TFIDFWeighter()

TFIDFWeighter(Properties properties)

Method Summary

Properties	getDefaultProperties()
Properties	getProperties()
java.lang.Object	getPropertyValue(java.lang.String name)
java.lang.String	getWeighterName() Returns a String that identifies the Weighter.
static java.util.HashMap<IObject,java.lang.Float>	globalWeightInGroupByGroup(IObjectGroup weightGroup, IObjectGroup correspondingGroup, IMatrix matrix, boolean row, Properties properties) The central global weighter.
static java.util.HashMap<IObject,java.util.HashMap<IObject,java.lang.Float>>	localWeightInGroupByGroup(IObjectGroup objectGroup, IObjectGroup representationGroup, IMatrix matrix, boolean row, Properties properties) The central local weighter.
static void	normalizeMatrix(IMatrix matrix, boolean row) Normalizes the rows or columns of the matrix.
void	setProperties(Properties properties)
void	setProperty(java.lang.String name, java.lang.Object value)
void	weight(IMatrix matrix) Weight the IMatrix (the whole matrix, which may be more than the current IObjectGroupings, the picture).

Methods inherited from class java.lang.Object

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

Constructor Detail

TFIDFWeighter

public TFIDFWeighter()

TFIDFWeighter

public TFIDFWeighter(Properties properties)

Method Detail

getDefaultProperties

public Properties getDefaultProperties()

getPropertyValue

public java.lang.Object getPropertyValue(java.lang.String name)

setProperty

public void setProperty(java.lang.String name,
                        java.lang.Object value)
                 throws PropertyNotFoundException

Throws:

PropertyNotFoundException

getProperties

public Properties getProperties()

setProperties

public void setProperties(Properties properties)

getWeighterName

public java.lang.String getWeighterName()

Description copied from class: Weighter

Returns a String that identifies the Weighter.

Specified by:

getWeighterName in class Weighter

weight

public void weight(IMatrix matrix)

Weight the IMatrix (the whole matrix, which may be more than the current IObjectGroupings, the picture).

Specified by:

weight in class Weighter

normalizeMatrix

public static void normalizeMatrix(IMatrix matrix,
                                   boolean row)

Normalizes the rows or columns of the matrix.

localWeightInGroupByGroup

public static java.util.HashMap<IObject,java.util.HashMap<IObject,java.lang.Float>> localWeightInGroupByGroup(IObjectGroup objectGroup,
                                                                                                              IObjectGroup representationGroup,
                                                                                                              IMatrix matrix,
                                                                                                              boolean row,
                                                                                                              Properties properties)

The central local weighter. The elements of the first group are considered objects, and those of the second their representation. The objects in the second are weighted accoring to occurences for each object in the first. For text-word: the words are weighted locally for each text. OBS. Only works in row-col order yet!!!

Parameters:

row - Wether the first group is along the rows of the matrix.

globalWeightInGroupByGroup

public static java.util.HashMap<IObject,java.lang.Float> globalWeightInGroupByGroup(IObjectGroup weightGroup,
                                                                                    IObjectGroup correspondingGroup,
                                                                                    IMatrix matrix,
                                                                                    boolean row,
                                                                                    Properties properties)

The central global weighter. Weights the elements of the first group by their occurences in the matrix corresponding to the second group.

Parameters:

row - Wether the first group is along the rows of the matrix.