weka.attributeSelection
Class RankSearch

java.lang.Object
  weka.attributeSelection.ASSearch
      weka.attributeSelection.RankSearch

All Implemented Interfaces:

OptionHandler, java.io.Serializable

public class RankSearch

extends ASSearch

implements OptionHandler

Class for evaluating a attribute ranking (given by a specified evaluator) using a specified subset evaluator.

Valid options are:

-A
Specify the attribute/subset evaluator to be used for generating the ranking. If a subset evaluator is specified then a forward selection search is used to produce a ranked list of attributes.

Version:

$Revision: 1.8 $

Author:

Mark Hall (mhall@cs.waikato.ac.nz)

See Also:

Serialized Form

Field Summary

private ASEvaluation	m_ASEval the attribute evaluator to use for generating the ranking
private java.util.BitSet	m_best_group the best subset found
private double	m_bestMerit the merit of the best subset found
private int	m_classIndex holds the class index
private boolean	m_hasClass does the data have a class
private Instances	m_Instances the training instances
private int	m_numAttribs number of attributes in the data
private int[]	m_Ranking will hold the attribute ranking
private ASEvaluation	m_SubsetEval the subset evaluator with which to evaluate the ranking

Constructor Summary

RankSearch()

Method Summary

java.lang.String	attributeEvaluatorTipText() Returns the tip text for this property
private int[]	attributeList(java.util.BitSet group) converts a BitSet into a list of attribute indexes
ASEvaluation	getAttributeEvaluator() Get the attribute evaluator used to generate the ranking.
java.lang.String[]	getOptions() Gets the current settings of WrapperSubsetEval.
java.lang.String	globalInfo() Returns a string describing this search method
java.util.Enumeration	listOptions() Returns an enumeration describing the available options.
protected void	resetOptions() Reset the search method.
int[]	search(ASEvaluation ASEval, Instances data) Ranks attributes using the specified attribute evaluator and then searches the ranking using the supplied subset evaluator.
void	setAttributeEvaluator(ASEvaluation newEvaluator) Set the attribute evaluator to use for generating the ranking.
void	setOptions(java.lang.String[] options) Parses a given list of options.
java.lang.String	toString() returns a description of the search as a String

Methods inherited from class weka.attributeSelection.ASSearch

forName

Methods inherited from class java.lang.Object

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

Field Detail

m_hasClass

private boolean m_hasClass

does the data have a class

m_classIndex

private int m_classIndex

holds the class index

m_numAttribs

private int m_numAttribs

number of attributes in the data

m_best_group

private java.util.BitSet m_best_group

the best subset found

m_ASEval

private ASEvaluation m_ASEval

the attribute evaluator to use for generating the ranking

m_SubsetEval

private ASEvaluation m_SubsetEval

the subset evaluator with which to evaluate the ranking

m_Instances

private Instances m_Instances

the training instances

m_bestMerit

private double m_bestMerit

the merit of the best subset found

m_Ranking

private int[] m_Ranking

will hold the attribute ranking

Constructor Detail

RankSearch

public RankSearch()

Method Detail

globalInfo

public java.lang.String globalInfo()

Returns a string describing this search method

Returns:

a description of the search method suitable for displaying in the explorer/experimenter gui

attributeEvaluatorTipText

public java.lang.String attributeEvaluatorTipText()

Returns the tip text for this property

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

setAttributeEvaluator

public void setAttributeEvaluator(ASEvaluation newEvaluator)

Set the attribute evaluator to use for generating the ranking.

Parameters:

newEvaluator - the attribute evaluator to use.

getAttributeEvaluator

public ASEvaluation getAttributeEvaluator()

Get the attribute evaluator used to generate the ranking.

Returns:

the evaluator used to generate the ranking.

listOptions

public java.util.Enumeration listOptions()

Returns an enumeration describing the available options.

Specified by:

listOptions in interface OptionHandler

Returns:

an enumeration of all the available options.

setOptions

public void setOptions(java.lang.String[] options)
                throws java.lang.Exception

Parses a given list of options. Valid options are:

-A

Specified by:

setOptions in interface OptionHandler

Parameters:

options - the list of options as an array of strings

Throws:

java.lang.Exception - if an option is not supported

getOptions

public java.lang.String[] getOptions()

Gets the current settings of WrapperSubsetEval.

Specified by:

getOptions in interface OptionHandler

Returns:

an array of strings suitable for passing to setOptions()

resetOptions

protected void resetOptions()

Reset the search method.

search

public int[] search(ASEvaluation ASEval,
                    Instances data)
             throws java.lang.Exception

Ranks attributes using the specified attribute evaluator and then searches the ranking using the supplied subset evaluator.

Specified by:

search in class ASSearch

Parameters:

data - the training instances.

ASEval - the attribute evaluator to guide the search

Returns:

an array (not necessarily ordered) of selected attribute indexes

Throws:

java.lang.Exception - if the search can't be completed

attributeList

private int[] attributeList(java.util.BitSet group)

converts a BitSet into a list of attribute indexes

Parameters:

group - the BitSet to convert

Returns:

an array of attribute indexes

toString

public java.lang.String toString()

returns a description of the search as a String

Returns:

a description of the search