Package weka.filters.unsupervised.attribute

Class ReplaceMissingValues

java.lang.Object

weka.filters.Filter

weka.filters.unsupervised.attribute.PotentialClassIgnorer

weka.filters.unsupervised.attribute.ReplaceMissingValues

All Implemented Interfaces:

Serializable, CapabilitiesHandler, CapabilitiesIgnorer, CommandlineRunnable, OptionHandler, RevisionHandler, WeightedAttributesHandler, WeightedInstancesHandler, Sourcable, UnsupervisedFilter

public class ReplaceMissingValues
extends PotentialClassIgnorer
implements UnsupervisedFilter, Sourcable, WeightedInstancesHandler, WeightedAttributesHandler

Replaces all missing values for nominal and numeric attributes in a dataset with the modes and means from the training data. The class attribute is skipped by default.

Valid options are:

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

Version:

$Revision: 14796 $

Author:

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

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
ReplaceMissingValues()

Method Summary

Modifier and Type	Method	Description
boolean	batchFinished()	Signify that this batch of input to the filter is finished.
Capabilities	getCapabilities()	Returns the Capabilities of this filter.
String	getRevision()	Returns the revision string.
String	globalInfo()	Returns a string describing this filter
boolean	input(Instance instance)	Input an instance for filtering.
static void	main(String[] argv)	Main method for testing this class.
boolean	setInputFormat(Instances instanceInfo)	Sets the format of the input instances.
String	toSource(String className, Instances data)	Returns a string that describes the filter as source.

Methods inherited from class weka.filters.unsupervised.attribute.PotentialClassIgnorer

getIgnoreClass, getOptions, getOutputFormat, ignoreClassTipText, listOptions, setIgnoreClass, setOptions

Methods inherited from class weka.filters.Filter

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

Methods inherited from class java.lang.Object

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

Constructor Details

ReplaceMissingValues

public ReplaceMissingValues()

Method Details

globalInfo

public String globalInfo()

Returns a string describing this filter

Returns:

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

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 PotentialClassIgnorer

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)

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:

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:

IllegalStateException - if no input structure has been defined

toSource

public String toSource(String className,
 Instances data)
                throws Exception

Returns a string that describes the filter as source. The filter will be contained in a class with the given name (there may be auxiliary classes), and will contain two methods with these signatures:

 
 // converts one row
 public static Object[] filter(Object[] i);
 // converts a full dataset (first dimension is row index)
 public static Object[][] filter(Object[][] i);
 
 

where the array i contains elements that are either Double, String, with missing values represented as null. The generated code is public domain and comes with no warranty.

Specified by:

toSource in interface Sourcable

Parameters:

className - the name that should be given to the source class.

data - the dataset used for initializing the filter

Returns:

the object source described by a string

Throws:

Exception - if the source can't be computed

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