weka.classifiers.meta.generators
Class NominalGenerator

java.lang.Object
  weka.classifiers.meta.generators.Generator
      weka.classifiers.meta.generators.RandomizableGenerator
          weka.classifiers.meta.generators.NominalGenerator

All Implemented Interfaces:

java.io.Serializable, NominalAttributeGenerator, OptionHandler

public class NominalGenerator
extends RandomizableGenerator
implements NominalAttributeGenerator

A generator for nominal attributes.

Generates artificial data for nominal attributes. Each attribute value is considered to be possible, i.e. the probability of any value is always non-zero.

Valid options are:

 -D
  If set, generator is run in debug mode and
  may output additional info to the console

 -S <seed>
  Sets the seed of the random number generator of the generator (default: 1)

Version:

$Revision: 5793 $

Author:

Kathryn Hempstalk (kah18 at cs.waikato.ac.nz)

See Also:

Serialized Form

Constructor Summary

NominalGenerator()

Method Summary

void	buildGenerator(Instances someinstances, Attribute att) Sets up the generator with the counts required for generation.
double	generate() Generates an index of a nominal attribute as artificial data.
double	getLogProbabilityOf(double valuex) Gets the (natural) log of the probability of a given value.
double	getProbabilityOf(double valuex) Gets the probability of a given attribute value (provided as an index).
java.lang.String	globalInfo() Returns a string describing this class' ability.

Methods inherited from class weka.classifiers.meta.generators.RandomizableGenerator

getOptions, getSeed, listOptions, seedTipText, setOptions, setSeed

Methods inherited from class weka.classifiers.meta.generators.Generator

copy, debugTipText, forName, getDebug, setDebug

Methods inherited from class java.lang.Object

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

Constructor Detail

NominalGenerator

public NominalGenerator()

Method Detail

globalInfo

public java.lang.String globalInfo()

Returns a string describing this class' ability.

Specified by:

globalInfo in class Generator

Returns:

A description of the class.

buildGenerator

public void buildGenerator(Instances someinstances,
                           Attribute att)

Sets up the generator with the counts required for generation.

Specified by:

buildGenerator in interface NominalAttributeGenerator

Parameters:

someinstances - The instances to count up.

att - The attribute to count up with.

generate

public double generate()

Generates an index of a nominal attribute as artificial data.

Specified by:

generate in class Generator

Returns:

The index of the nominal attribute's value.

getProbabilityOf

public double getProbabilityOf(double valuex)

Gets the probability of a given attribute value (provided as an index).

Specified by:

getProbabilityOf in class Generator

Parameters:

valuex - The index to the attribute value.

Returns:

The probability of this value.

getLogProbabilityOf

public double getLogProbabilityOf(double valuex)

Gets the (natural) log of the probability of a given value.

Specified by:

getLogProbabilityOf in class Generator

Parameters:

valuex - The index of the nominal value.

Returns:

The natural log of the probability of valuex.