weka.filters.supervised.attribute
Class NominalToBinary

java.lang.Object
  |
  +--weka.filters.Filter
        |
        +--weka.filters.supervised.attribute.NominalToBinary

All Implemented Interfaces:

OptionHandler, java.io.Serializable, SupervisedFilter

public class NominalToBinary

extends Filter

implements SupervisedFilter, OptionHandler

Converts all nominal attributes into binary numeric attributes. An attribute with k values is transformed into k binary attributes if the class is nominal (using the one-attribute-per-value approach). Binary attributes are left binary. If the class is numeric, k - 1 new binary attributes are generated (in the manner described in "Classification and Regression Trees").

Valid filter-specific options are:

-N
If binary attributes are to be coded as nominal ones.

Version:

$Revision: 1.2 $

Author:

Eibe Frank (eibe@cs.waikato.ac.nz)

See Also:

Serialized Form

Constructor Summary

NominalToBinary()

Method Summary

boolean	batchFinished() Signify that this batch of input to the filter is finished.
java.lang.String	binaryAttributesNominalTipText() Returns the tip text for this property
boolean	getBinaryAttributesNominal() Gets if binary attributes are to be treated as nominal ones.
java.lang.String[]	getOptions() Gets the current settings of the filter.
java.lang.String	globalInfo() Returns a string describing this filter
boolean	input(Instance instance) Input an instance for filtering.
java.util.Enumeration	listOptions() Returns an enumeration describing the available options.
static void	main(java.lang.String[] argv) Main method for testing this class.
void	setBinaryAttributesNominal(boolean bool) Sets if binary attributes are to be treates as nominal ones.
boolean	setInputFormat(Instances instanceInfo) Sets the format of the input instances.
void	setOptions(java.lang.String[] options) Parses the options for this object.

Methods inherited from class weka.filters.Filter

batchFilterFile, filterFile, getOutputFormat, inputFormat, isOutputFormatDefined, numPendingOutput, output, outputFormat, outputPeek, useFilter

Methods inherited from class java.lang.Object

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

Constructor Detail

NominalToBinary

public NominalToBinary()

Method Detail

globalInfo

public java.lang.String globalInfo()

Returns a string describing this filter

Returns:

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

setInputFormat

public boolean setInputFormat(Instances instanceInfo)
                       throws java.lang.Exception

Sets the format of the input instances.

Overrides:

setInputFormat in class Filter

Parameters:

instanceInfo - an Instances object containing the input instance structure (any instances contained in the object are ignored - only the structure is required).

Returns:

true if the outputFormat may be collected immediately

Throws:

java.lang.Exception - if the input format can't be set successfully

input

public boolean input(Instance instance)

Input an instance for filtering. Filter requires all training instances be read before producing output.

Overrides:

input in class Filter

Parameters:

instance - the input instance

Returns:

true if the filtered instance may now be collected with output().

Throws:

java.lang.IllegalStateException - if no input format has been set

batchFinished

public boolean batchFinished()

Signify that this batch of input to the filter is finished. If the filter requires all instances prior to filtering, output() may now be called to retrieve the filtered instances.

Overrides:

batchFinished in class Filter

Returns:

true if there are instances pending output

Throws:

java.lang.IllegalStateException - if no input structure has been defined

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 the options for this object. Valid options are:

-N
If binary attributes are to be coded as nominal ones.

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 the filter.

Specified by:

getOptions in interface OptionHandler

Returns:

an array of strings suitable for passing to setOptions

binaryAttributesNominalTipText

public java.lang.String binaryAttributesNominalTipText()

Returns the tip text for this property

Returns:

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

getBinaryAttributesNominal

public boolean getBinaryAttributesNominal()

Gets if binary attributes are to be treated as nominal ones.

Returns:

true if binary attributes are to be treated as nominal ones

setBinaryAttributesNominal

public void setBinaryAttributesNominal(boolean bool)

Sets if binary attributes are to be treates as nominal ones.

Parameters:

bool - true if binary attributes are to be treated as nominal ones

main

public static void main(java.lang.String[] argv)

Main method for testing this class.

Parameters:

argv - should contain arguments to the filter: use -h for help