weka.filters.unsupervised.attribute

Class RandomSubset

java.lang.Object

weka.filters.Filter

weka.filters.SimpleFilter

weka.filters.SimpleStreamFilter

weka.filters.unsupervised.attribute.RandomSubset

All Implemented Interfaces:

java.io.Serializable, CapabilitiesHandler, CapabilitiesIgnorer, CommandlineRunnable, OptionHandler, Randomizable, RevisionHandler, WeightedAttributesHandler, WeightedInstancesHandler, StreamableFilter

public class RandomSubset
extends SimpleStreamFilter
implements Randomizable, WeightedInstancesHandler, WeightedAttributesHandler

Chooses a random subset of attributes, either an absolute number or a percentage. The class is always included in the output (as the last attribute).

Valid options are:

 -N <double>
  The number of attributes to randomly select.
  If < 1 then percentage, >= 1 absolute number.
  (default: 0.5)

 -V
  Invert selection - i.e. randomly remove rather than select.

 -S <int>
  The seed value.
  (default: 1)

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

 -do-not-check-capabilities
  If set, filter capabilities are not checked before filter is built
  (use with caution).

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected int[]	m_Indices The indices of the attributes that got selected.
protected boolean	m_invertSelection Whether to randomly remove rather than select
protected double	m_NumAttributes The number of attributes to randomly choose (>= 1 absolute number of attributes, < 1 percentage).
protected int	m_Seed The seed value.

Fields inherited from class weka.filters.Filter

m_Debug, m_DoNotCheckCapabilities, m_FirstBatchDone, m_InputRelAtts, m_InputStringAtts, m_NewBatch, m_OutputRelAtts, m_OutputStringAtts

Constructor Summary

Constructors

Constructor and Description
RandomSubset()

Method Summary

Modifier and Type	Method and Description
protected Instances	determineOutputFormat(Instances inputFormat) Determines the output format based on the input format and returns this.
Capabilities	getCapabilities() Returns the Capabilities of this filter.
boolean	getInvertSelection() Get whether to invert the selection - i.e. randomly remove rather than select attributes.
double	getNumAttributes() Get the number of attributes (< 1 percentage, >= 1 absolute number).
java.lang.String[]	getOptions() Gets the current settings of the filter.
java.lang.String	getRevision() Returns the revision string.
int	getSeed() Get the seed value for the random number generator.
java.lang.String	globalInfo() Returns a string describing this filter.
java.lang.String	invertSelectionTipText() Returns the tip text for this property.
java.util.Enumeration<Option>	listOptions() Returns an enumeration describing the available options.
static void	main(java.lang.String[] args) Runs the filter with the given parameters.
java.lang.String	numAttributesTipText() Returns the tip text for this property.
protected Instance	process(Instance instance) processes the given instance (may change the provided instance) and returns the modified version.
java.lang.String	seedTipText() Returns the tip text for this property.
void	setInvertSelection(boolean inv) Set whether to invert the selection - i.e. randomly remove rather than select attributes.
void	setNumAttributes(double value) Set the number of attributes.
void	setOptions(java.lang.String[] options) Parses a given list of options.
void	setSeed(int value) Set the seed value for the random number generator.

Methods inherited from class weka.filters.SimpleStreamFilter

batchFinished, hasImmediateOutputFormat, input, preprocess, process

Methods inherited from class weka.filters.SimpleFilter

reset, setInputFormat

Methods inherited from class weka.filters.Filter

batchFilterFile, bufferInput, copyValues, copyValues, debugTipText, doNotCheckCapabilitiesTipText, filterFile, flushInput, getCapabilities, getCopyOfInputFormat, getDebug, getDoNotCheckCapabilities, getInputFormat, getOutputFormat, initInputLocators, initOutputLocators, inputFormatPeek, isFirstBatchDone, isNewBatch, isOutputFormatDefined, makeCopies, makeCopy, mayRemoveInstanceAfterFirstBatchDone, numPendingOutput, output, outputFormatPeek, outputPeek, postExecution, preExecution, push, push, resetQueue, run, runFilter, setDebug, setDoNotCheckCapabilities, setOutputFormat, testInputFormat, toString, useFilter, wekaStaticWrapper

Methods inherited from class java.lang.Object

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

Field Detail

m_NumAttributes

protected double m_NumAttributes

The number of attributes to randomly choose (>= 1 absolute number of attributes, < 1 percentage).

m_Seed

protected int m_Seed

The seed value.

m_Indices

protected int[] m_Indices

The indices of the attributes that got selected.

m_invertSelection

protected boolean m_invertSelection

Whether to randomly remove rather than select

Constructor Detail

RandomSubset

public RandomSubset()

Method Detail

globalInfo

public java.lang.String globalInfo()

Returns a string describing this filter.

Specified by:

globalInfo in class SimpleFilter

Returns:

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

listOptions

public java.util.Enumeration<Option> listOptions()

Returns an enumeration describing the available options.

Specified by:

listOptions in interface OptionHandler

Overrides:

listOptions in class Filter

Returns:

an enumeration of all the available options.

getOptions

public java.lang.String[] getOptions()

Gets the current settings of the filter.

Specified by:

getOptions in interface OptionHandler

Overrides:

getOptions in class Filter

Returns:

an array of strings suitable for passing to setOptions

setOptions

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

Parses a given list of options.

Valid options are:

 -N <double>
  The number of attributes to randomly select.
  If < 1 then percentage, >= 1 absolute number.
  (default: 0.5)

 -V
  Invert selection - i.e. randomly remove rather than select.

 -S <int>
  The seed value.
  (default: 1)

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

 -do-not-check-capabilities
  If set, filter capabilities are not checked before filter is built
  (use with caution).

Specified by:

setOptions in interface OptionHandler

Overrides:

setOptions in class Filter

Parameters:

options - the list of options as an array of strings

Throws:

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

numAttributesTipText

public java.lang.String numAttributesTipText()

Returns the tip text for this property.

Returns:

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

getNumAttributes

public double getNumAttributes()

Get the number of attributes (< 1 percentage, >= 1 absolute number).

Returns:

the number of attributes.

setNumAttributes

public void setNumAttributes(double value)

Set the number of attributes.

Parameters:

value - the number of attributes to use.

invertSelectionTipText

public java.lang.String invertSelectionTipText()

Returns the tip text for this property.

Returns:

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

setInvertSelection

public void setInvertSelection(boolean inv)

Set whether to invert the selection - i.e. randomly remove rather than select attributes.

Parameters:

inv - true if the selection should be inverted

getInvertSelection

public boolean getInvertSelection()

Get whether to invert the selection - i.e. randomly remove rather than select attributes.

Returns:

true if the selection should be inverted

seedTipText

public java.lang.String seedTipText()

Returns the tip text for this property.

Returns:

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

getSeed

public int getSeed()

Get the seed value for the random number generator.

Specified by:

getSeed in interface Randomizable

Returns:

the seed value.

setSeed

public void setSeed(int value)

Set the seed value for the random number generator.

Specified by:

setSeed in interface Randomizable

Parameters:

value - the seed value.

getCapabilities

public Capabilities getCapabilities()

Returns the Capabilities of this filter.

Specified by:

getCapabilities in interface CapabilitiesHandler

Overrides:

getCapabilities in class Filter

Returns:

the capabilities of this object

See Also:

Capabilities

determineOutputFormat

protected Instances determineOutputFormat(Instances inputFormat)
                                   throws java.lang.Exception

Determines the output format based on the input format and returns this. In case the output format cannot be returned immediately, i.e., hasImmediateOutputFormat() returns false, then this method will called from batchFinished() after the call of preprocess(Instances), in which, e.g., statistics for the actual processing step can be gathered.

Specified by:

determineOutputFormat in class SimpleStreamFilter

Parameters:

inputFormat - the input format to base the output format on

Returns:

the output format

Throws:

java.lang.Exception - in case the determination goes wrong

See Also:

SimpleStreamFilter.hasImmediateOutputFormat(), SimpleStreamFilter.batchFinished(), SimpleStreamFilter.preprocess(Instances)

process

protected Instance process(Instance instance)
                    throws java.lang.Exception

processes the given instance (may change the provided instance) and returns the modified version.

Specified by:

process in class SimpleStreamFilter

Parameters:

instance - the instance to process

Returns:

the modified data

Throws:

java.lang.Exception - in case the processing goes wrong

getRevision

public java.lang.String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Overrides:

getRevision in class Filter

Returns:

the revision

main

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

Runs the filter with the given parameters. Use -h to list options.

Parameters:

args - the commandline options