weka.filters.unsupervised.attribute

Class ReplaceWithMissingValue

java.lang.Object

weka.filters.Filter

weka.filters.SimpleFilter

weka.filters.SimpleBatchFilter

weka.filters.unsupervised.attribute.ReplaceWithMissingValue

All Implemented Interfaces:

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

public class ReplaceWithMissingValue
extends SimpleBatchFilter
implements UnsupervisedFilter, Randomizable, WeightedAttributesHandler, WeightedInstancesHandler

A filter that can be used to introduce missing values in a dataset. The specified probability is used to flip a biased coin to decide whether to replace a particular attribute value in an instance with a missing value (i.e., a probability of 0.9 means 90% of values will be replaced with missing values). This filter only modifies the first batch of data that is processed. The class attribute is skipped by default.

Valid options are:

 -R <col1,col2-col4,...>
  Specifies list of columns to modify. First and last are valid indexes.
  (default: first-last)

 -V
  Invert matching sense of column indexes.

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

 -P <double>
  Specify the probability  (default 0.1)

 -unset-class-temporarily
  Unsets the class index temporarily before the filter is
  applied to the data.
  (default: no)

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected Range	m_Cols Stores which columns to turn into nominals
protected java.lang.String	m_DefaultCols The default columns to turn into nominals
protected boolean	m_IgnoreClass True if the class is to be unset
protected double	m_Probability The probability
protected int	m_Seed The seed for the random number generator

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
ReplaceWithMissingValue()

Method Summary

Modifier and Type	Method and Description
java.lang.String	attributeIndicesTipText() Returns the tip text for this property
protected Instances	determineOutputFormat(Instances inputFormat) Determines the output format based on the input format and returns this.
java.lang.String	getAttributeIndices() Gets the current range selection
Capabilities	getCapabilities() Returns the Capabilities of this filter.
boolean	getIgnoreClass() Gets the IgnoreClass value.
boolean	getInvertSelection() Gets whether the supplied columns are to be worked on or the others.
java.lang.String[]	getOptions() Gets the current settings of the filter.
double	getProbability() Get the probability.
java.lang.String	getRevision() Returns the revision string.
int	getSeed() Get the random number generator seed value.
java.lang.String	globalInfo() Returns a string describing this filter.
protected boolean	hasImmediateOutputFormat() returns true if the output format is immediately available after the input format has been set and not only after all the data has been seen (see batchFinished())
java.lang.String	ignoreClassTipText() Returns the tip text for this property
java.lang.String	invertSelectionTipText() Returns the tip text for this property
java.util.Enumeration<Option>	listOptions() Gets an enumeration describing the available options.
static void	main(java.lang.String[] argv) Main method for testing this class.
java.lang.String	probabilityTipText() Returns the tip text for this property
protected Instances	process(Instances instances) Processes the given data (may change the provided dataset) and returns the modified version.
java.lang.String	seedTipText() Returns the tip text for this property
void	setAttributeIndices(java.lang.String value) Sets which attributes are to be "nominalized" (only numeric attributes among the selection will be transformed).
void	setAttributeIndicesArray(int[] value) Sets which attributes are to be transoformed to nominal.
void	setIgnoreClass(boolean newIgnoreClass) Set the IgnoreClass value.
void	setInvertSelection(boolean value) Sets whether selected columns should be worked on or all the others apart from these.
void	setOptions(java.lang.String[] options) Parses a given list of options.
void	setProbability(double newProbability) Set the probability to use.
void	setSeed(int newSeed) Set the random number generator seed value.

Methods inherited from class weka.filters.SimpleBatchFilter

allowAccessToFullInputFormat, batchFinished, input

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_Cols

protected Range m_Cols

Stores which columns to turn into nominals

m_DefaultCols

protected java.lang.String m_DefaultCols

The default columns to turn into nominals

m_Seed

protected int m_Seed

The seed for the random number generator

m_Probability

protected double m_Probability

The probability

m_IgnoreClass

protected boolean m_IgnoreClass

True if the class is to be unset

Constructor Detail

ReplaceWithMissingValue

public ReplaceWithMissingValue()

Method Detail

listOptions

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

Gets 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(java.lang.String[] options)
                throws java.lang.Exception

Parses a given list of options.

Valid options are:

 -R <col1,col2-col4,...>
  Specifies list of columns to modify. First and last are valid indexes.
  (default: first-last)

 -V
  Invert matching sense of column indexes.

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

 -P <double>
  Specify the probability  (default 0.1)

 -unset-class-temporarily
  Unsets the class index temporarily before the filter is
  applied to the data.
  (default: no)

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

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

ignoreClassTipText

public java.lang.String ignoreClassTipText()

Returns the tip text for this property

Returns:

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

setIgnoreClass

public void setIgnoreClass(boolean newIgnoreClass)

Set the IgnoreClass value. Set this to true if the class index is to be unset before the filter is applied.

Parameters:

newIgnoreClass - The new IgnoreClass value.

getIgnoreClass

public boolean getIgnoreClass()

Gets the IgnoreClass value. If this to true then the class index is to unset before the filter is applied.

Returns:

the current IgnoreClass value.

probabilityTipText

public java.lang.String probabilityTipText()

Returns the tip text for this property

Returns:

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

getProbability

public double getProbability()

Get the probability.

Returns:

the probability.

setProbability

public void setProbability(double newProbability)

Set the probability to use.

Parameters:

newProbability - the probability to use.

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 random number generator seed value.

Specified by:

getSeed in interface Randomizable

Returns:

random number generator seed value.

setSeed

public void setSeed(int newSeed)

Set the random number generator seed value.

Specified by:

setSeed in interface Randomizable

Parameters:

newSeed - value to use as the random number generator seed.

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

getInvertSelection

public boolean getInvertSelection()

Gets whether the supplied columns are to be worked on or the others.

Returns:

true if the supplied columns will be worked on

setInvertSelection

public void setInvertSelection(boolean value)

Sets whether selected columns should be worked on or all the others apart from these. If true all the other columns are considered for "nominalization".

Parameters:

value - the new invert setting

attributeIndicesTipText

public java.lang.String attributeIndicesTipText()

Returns the tip text for this property

Returns:

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

getAttributeIndices

public java.lang.String getAttributeIndices()

Gets the current range selection

Returns:

a string containing a comma separated list of ranges

setAttributeIndices

public void setAttributeIndices(java.lang.String value)

Sets which attributes are to be "nominalized" (only numeric attributes among the selection will be transformed).

Parameters:

value - a string representing the list of attributes. Since the string will typically come from a user, attributes are indexed from 1.
eg: first-3,5,6-last

Throws:

java.lang.IllegalArgumentException - if an invalid range list is supplied

setAttributeIndicesArray

public void setAttributeIndicesArray(int[] value)

Sets which attributes are to be transoformed to nominal. (only numeric attributes among the selection will be transformed).

Parameters:

value - an array containing indexes of attributes to nominalize. Since the array will typically come from a program, attributes are indexed from 0.

Throws:

java.lang.IllegalArgumentException - if an invalid set of ranges is supplied

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

hasImmediateOutputFormat

protected boolean hasImmediateOutputFormat()

returns true if the output format is immediately available after the input format has been set and not only after all the data has been seen (see batchFinished())

Overrides:

hasImmediateOutputFormat in class SimpleBatchFilter

Returns:

true

See Also:

SimpleBatchFilter.batchFinished(), SimpleFilter.setInputFormat(Instances)

determineOutputFormat

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

Determines the output format based on the input format and returns this.

Specified by:

determineOutputFormat in class SimpleFilter

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:

SimpleFilter.hasImmediateOutputFormat(), Filter.batchFinished()

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

process

protected Instances process(Instances instances)
                     throws java.lang.Exception

Processes the given data (may change the provided dataset) and returns the modified version. This method is called in batchFinished().

Specified by:

process in class SimpleFilter

Parameters:

instances - the data to process

Returns:

the modified data

Throws:

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

See Also:

SimpleBatchFilter.batchFinished()

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[] argv)

Main method for testing this class.

Parameters:

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