weka.attributeSelection
Class ASEvaluation

java.lang.Object
  |
  +--weka.attributeSelection.ASEvaluation

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

AttributeEvaluator, SubsetEvaluator

public abstract class ASEvaluation

extends java.lang.Object

implements java.io.Serializable

Abstract attribute selection evaluation class

Author:

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

See Also:

Serialized Form

Constructor Summary

ASEvaluation()

Method Summary

abstract void	buildEvaluator(Instances data) Generates a attribute evaluator.
static ASEvaluation	forName(java.lang.String evaluatorName, java.lang.String[] options) Creates a new instance of an attribute/subset evaluator given it's class name and (optional) arguments to pass to it's setOptions method.
static ASEvaluation[]	makeCopies(ASEvaluation model, int num) Creates copies of the current evaluator.
int[]	postProcess(int[] attributeSet) Provides a chance for a attribute evaluator to do any special post processing of the selected attribute set.

Methods inherited from class java.lang.Object

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

Constructor Detail

ASEvaluation

public ASEvaluation()

Method Detail

buildEvaluator

public abstract void buildEvaluator(Instances data)
                             throws java.lang.Exception

Generates a attribute evaluator. Has to initialize all fields of the evaluator that are not being set via options.

Parameters:

data - set of instances serving as training data

Throws:

java.lang.Exception - if the evaluator has not been generated successfully

postProcess

public int[] postProcess(int[] attributeSet)
                  throws java.lang.Exception

Provides a chance for a attribute evaluator to do any special post processing of the selected attribute set.

Parameters:

attributeSet - the set of attributes found by the search

Returns:

a possibly ranked list of postprocessed attributes

Throws:

java.lang.Exception - if postprocessing fails for some reason

forName

public static ASEvaluation forName(java.lang.String evaluatorName,
                                   java.lang.String[] options)
                            throws java.lang.Exception

Creates a new instance of an attribute/subset evaluator given it's class name and (optional) arguments to pass to it's setOptions method. If the evaluator implements OptionHandler and the options parameter is non-null, the evaluator will have it's options set.

Parameters:

evaluatorName - the fully qualified class name of the evaluator

options - an array of options suitable for passing to setOptions. May be null.

Returns:

the newly created evaluator, ready for use.

Throws:

java.lang.Exception - if the evaluator name is invalid, or the options supplied are not acceptable to the evaluator

makeCopies

public static ASEvaluation[] makeCopies(ASEvaluation model,
                                        int num)
                                 throws java.lang.Exception

Creates copies of the current evaluator. Note that this method now uses Serialization to perform a deep copy, so the evaluator object must be fully Serializable. Any currently built model will now be copied as well.

Parameters:

model - an example evaluator to copy

num - the number of evaluator copies to create.

Returns:

an array of evaluators.

Throws:

java.lang.Exception - if an error occurs