weka.filters.unsupervised.instance
Class Resample

java.lang.Object
  extended by weka.filters.Filter
      extended by weka.filters.unsupervised.instance.Resample
All Implemented Interfaces:
java.io.Serializable, CapabilitiesHandler, OptionHandler, RevisionHandler, UnsupervisedFilter

public class Resample
extends Filter
implements UnsupervisedFilter, OptionHandler

Produces a random subsample of a dataset using either sampling with replacement or without replacement. The original dataset must fit entirely in memory. The number of instances in the generated dataset may be specified. When used in batch mode, subsequent batches are NOT resampled.

Valid options are:

 -S <num>
  Specify the random number seed (default 1)
 -Z <num>
  The size of the output dataset, as a percentage of
  the input dataset (default 100)
 -no-replacement
  Disables replacement of instances
  (default: with replacement)
 -V
  Inverts the selection - only available with '-no-replacement'.

Version:
$Revision: 5548 $
Author:
Len Trigg (len@reeltwo.com), FracPete (fracpete at waikato dot ac dot nz)
See Also:
Serialized Form

Constructor Summary
Resample()
           
 
Method Summary
 boolean batchFinished()
          Signify that this batch of input to the filter is finished.
 void createSubsampleWithoutReplacement(java.util.Random random, int origSize, int sampleSize)
          creates the subsample without replacement
 void createSubsampleWithReplacement(java.util.Random random, int origSize, int sampleSize)
          creates the subsample with replacement
 Capabilities getCapabilities()
          Returns the Capabilities of this filter.
 boolean getInvertSelection()
          Gets whether selection is inverted (only if instances are drawn WIHTOUT replacement).
 boolean getNoReplacement()
          Gets whether instances are drawn with or without replacement.
 java.lang.String[] getOptions()
          Gets the current settings of the filter.
 int getRandomSeed()
          Gets the random number seed.
 java.lang.String getRevision()
          Returns the revision string.
 double getSampleSizePercent()
          Gets the subsample size as a percentage of the original set.
 java.lang.String globalInfo()
          Returns a string describing this classifier
 boolean input(Instance instance)
          Input an instance for filtering.
 java.lang.String invertSelectionTipText()
          Returns the tip text for this property
 java.util.Enumeration listOptions()
          Returns an enumeration describing the available options.
static void main(java.lang.String[] argv)
          Main method for testing this class.
 java.lang.String noReplacementTipText()
          Returns the tip text for this property
 java.lang.String randomSeedTipText()
          Returns the tip text for this property
 java.lang.String sampleSizePercentTipText()
          Returns the tip text for this property
 boolean setInputFormat(Instances instanceInfo)
          Sets the format of the input instances.
 void setInvertSelection(boolean value)
          Sets whether the selection is inverted (only if instances are drawn WIHTOUT replacement).
 void setNoReplacement(boolean value)
          Sets whether instances are drawn with or with out replacement.
 void setOptions(java.lang.String[] options)
          Parses a given list of options.
 void setRandomSeed(int newSeed)
          Sets the random number seed.
 void setSampleSizePercent(double newSampleSizePercent)
          Sets the size of the subsample, as a percentage of the original set.
 
Methods inherited from class weka.filters.Filter
batchFilterFile, filterFile, getCapabilities, getOutputFormat, isFirstBatchDone, isNewBatch, isOutputFormatDefined, makeCopies, makeCopy, numPendingOutput, output, outputPeek, toString, useFilter, wekaStaticWrapper
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

Resample

public Resample()
Method Detail

globalInfo

public java.lang.String globalInfo()
Returns a string describing this classifier

Returns:
a description of the classifier suitable for displaying in the explorer/experimenter gui

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 a given list of options.

Valid options are:

 -S <num>
  Specify the random number seed (default 1)
 -Z <num>
  The size of the output dataset, as a percentage of
  the input dataset (default 100)
 -no-replacement
  Disables replacement of instances
  (default: with replacement)
 -V
  Inverts the selection - only available with '-no-replacement'.

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

randomSeedTipText

public java.lang.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.

sampleSizePercentTipText

public java.lang.String sampleSizePercentTipText()
Returns the tip text for this property

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

getSampleSizePercent

public double getSampleSizePercent()
Gets the subsample size as a percentage of the original set.

Returns:
the subsample size

setSampleSizePercent

public void setSampleSizePercent(double newSampleSizePercent)
Sets the size of the subsample, as a percentage of the original set.

Parameters:
newSampleSizePercent - the subsample set size, between 0 and 100.

noReplacementTipText

public java.lang.String noReplacementTipText()
Returns the tip text for this property

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

getNoReplacement

public boolean getNoReplacement()
Gets whether instances are drawn with or without replacement.

Returns:
true if the replacement is disabled

setNoReplacement

public void setNoReplacement(boolean value)
Sets whether instances are drawn with or with out replacement.

Parameters:
value - if true then the replacement of instances is disabled

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 selection is inverted (only if instances are drawn WIHTOUT replacement).

Returns:
true if the replacement is disabled
See Also:
m_NoReplacement

setInvertSelection

public void setInvertSelection(boolean value)
Sets whether the selection is inverted (only if instances are drawn WIHTOUT replacement).

Parameters:
value - if true then selection is inverted

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 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 structure has been defined

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

createSubsampleWithReplacement

public void createSubsampleWithReplacement(java.util.Random random,
                                           int origSize,
                                           int sampleSize)
creates the subsample with replacement

Parameters:
random - the random number generator to use
origSize - the original size of the dataset
sampleSize - the size to generate

createSubsampleWithoutReplacement

public void createSubsampleWithoutReplacement(java.util.Random random,
                                              int origSize,
                                              int sampleSize)
creates the subsample without replacement

Parameters:
random - the random number generator to use
origSize - the original size of the dataset
sampleSize - the size to generate

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