weka.filters.unsupervised.attribute

Class AddNoise

java.lang.Object

weka.filters.Filter

weka.filters.unsupervised.attribute.AddNoise

All Implemented Interfaces:

Serializable, CapabilitiesHandler, CapabilitiesIgnorer, OptionHandler, RevisionHandler, UnsupervisedFilter

public class AddNoise
extends Filter
implements UnsupervisedFilter, OptionHandler

An instance filter that changes a percentage of a given attributes values. The attribute must be nominal. Missing value can be treated as value itself.

Valid options are:

 -C <col>
  Index of the attribute to be changed 
  (default last attribute)
 

 -M
  Treat missing values as an extra value
 

 -P <num>
  Specify the percentage of noise introduced 
  to the data (default 10)
 

 -S <num>
  Specify the random number seed (default 1)
 

Version:

$Revision: 10215 $

Author:

Gabi Schmidberger (gabi@cs.waikato.ac.nz)

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AddNoise()

Method Summary

Methods

Modifier and Type	Method and Description
void	addNoise(Instances instances, int seed, int percent, int attIndex, boolean useMissing) add noise to the dataset a given percentage of the instances are changed in the way, that a set of instances are randomly selected using seed.
String	attributeIndexTipText() Returns the tip text for this property
boolean	batchFinished() Signify that this batch of input to the filter is finished.
String	getAttributeIndex() Get the index of the attribute used.
Capabilities	getCapabilities() Returns the Capabilities of this filter.
String[]	getOptions() Gets the current settings of the filter.
int	getPercent() Gets the size of noise data as a percentage of the original set.
int	getRandomSeed() Gets the random number seed.
String	getRevision() Returns the revision string.
boolean	getUseMissing() Gets the flag if missing values are treated as extra values.
String	globalInfo() Returns a string describing this filter
boolean	input(Instance instance) Input an instance for filtering.
Enumeration<Option>	listOptions() Returns an enumeration describing the available options
static void	main(String[] argv) Main method for testing this class.
String	percentTipText() Returns the tip text for this property
String	randomSeedTipText() Returns the tip text for this property
void	setAttributeIndex(String attIndex) Sets index of the attribute used.
boolean	setInputFormat(Instances instanceInfo) Sets the format of the input instances.
void	setOptions(String[] options) Parses a given list of options.
void	setPercent(int newPercent) Sets the size of noise data, as a percentage of the original set.
void	setRandomSeed(int newSeed) Sets the random number seed.
void	setUseMissing(boolean newUseMissing) Sets the flag if missing values are treated as extra values.
String	useMissingTipText() Returns the tip text for this property

Methods inherited from class weka.filters.Filter

batchFilterFile, debugTipText, doNotCheckCapabilitiesTipText, filterFile, getCapabilities, getDebug, getDoNotCheckCapabilities, getOutputFormat, isFirstBatchDone, isNewBatch, isOutputFormatDefined, makeCopies, makeCopy, mayRemoveInstanceAfterFirstBatchDone, numPendingOutput, output, outputPeek, runFilter, setDebug, setDoNotCheckCapabilities, toString, useFilter, wekaStaticWrapper

Methods inherited from class java.lang.Object

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

Constructor Detail

AddNoise

public AddNoise()

Method Detail

globalInfo

public String globalInfo()

Returns a string describing this filter

Returns:

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

listOptions

public 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

setOptions

public void setOptions(String[] options)
                throws Exception

Parses a given list of options.

Valid options are:

 -C <col>
  Index of the attribute to be changed 
  (default last attribute)
 

 -M
  Treat missing values as an extra value
 

 -P <num>
  Specify the percentage of noise introduced 
  to the data (default 10)
 

 -S <num>
  Specify the random number seed (default 1)
 

Specified by:

setOptions in interface OptionHandler

Overrides:

setOptions in class Filter

Parameters:

options - the list of options as an array of strings

Throws:

Exception - if an option is not supported

getOptions

public 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

useMissingTipText

public String useMissingTipText()

Returns the tip text for this property

Returns:

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

getUseMissing

public boolean getUseMissing()

Gets the flag if missing values are treated as extra values.

Returns:

the flag missing values.

setUseMissing

public void setUseMissing(boolean newUseMissing)

Sets the flag if missing values are treated as extra values.

Parameters:

newUseMissing - the new flag value.

randomSeedTipText

public String randomSeedTipText()

Returns the tip text for this property

Returns:

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

getRandomSeed

public int getRandomSeed()

Gets the random number seed.

Returns:

the random number seed.

setRandomSeed

public void setRandomSeed(int newSeed)

Sets the random number seed.

Parameters:

newSeed - the new random number seed.

percentTipText

public String percentTipText()

Returns the tip text for this property

Returns:

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

getPercent

public int getPercent()

Gets the size of noise data as a percentage of the original set.

Returns:

the noise data size

setPercent

public void setPercent(int newPercent)

Sets the size of noise data, as a percentage of the original set.

Parameters:

newPercent - the subsample set size, between 0 and 100.

attributeIndexTipText

public String attributeIndexTipText()

Returns the tip text for this property

Returns:

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

getAttributeIndex

public String getAttributeIndex()

Get the index of the attribute used.

Returns:

the index of the attribute

setAttributeIndex

public void setAttributeIndex(String attIndex)

Sets index of the attribute used.

Parameters:

attIndex - the index of the attribute

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

setInputFormat

public boolean setInputFormat(Instances instanceInfo)
                       throws 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:

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

input

public boolean input(Instance instance)
              throws Exception

Input an instance for filtering.

Overrides:

input in class Filter

Parameters:

instance - the input instance

Returns:

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

Throws:

Exception - if the input format was not set

batchFinished

public boolean batchFinished()
                      throws Exception

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:

Exception - if no input structure has been defined

addNoise

public void addNoise(Instances instances,
            int seed,
            int percent,
            int attIndex,
            boolean useMissing)

add noise to the dataset a given percentage of the instances are changed in the way, that a set of instances are randomly selected using seed. The attribute given by its index is changed from its current value to one of the other possibly ones, also randomly. This is done with leaving the apportion the same. if m_UseMissing is true, missing value is used as a value of its own

Parameters:

instances - is the dataset

seed - used for random function

percent - percentage of instances that are changed

attIndex - index of the attribute changed

useMissing - if true missing values are treated as extra value

getRevision

public 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(String[] argv)

Main method for testing this class.

Parameters:

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