ReservoirSample

java.lang.Object
- weka.filters.Filter
- - weka.filters.unsupervised.instance.ReservoirSample

All Implemented Interfaces:: java.io.Serializable, CapabilitiesHandler, OptionHandler, RevisionHandler, StreamableFilter, UnsupervisedFilter

public class ReservoirSample
extends Filter
implements UnsupervisedFilter, OptionHandler, StreamableFilter

Produces a random subsample of a dataset using the reservoir sampling Algorithm "R" by Vitter. The original data set does not have to fit into main memory, but the reservoir does.

BibTeX:

 @article{Vitter1985,
    author = {J. S. Vitter},
    journal = {ACM Transactions on Mathematical Software},
    number = {1}
    volume = {11}
    pages = {37-57},
    title = {Random Sampling with a Reservoir},
    year = {1985}
 }

Valid options are:

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

 -Z <num>
  The size of the output dataset - number of instances
  (default 100)

Version:: $Revision: 5562 $
Author:: Mark Hall (mhall{[at]}pentaho{[dot]}org)
See Also:: Serialized Form

Constructor Summary

Constructors
Constructor and Description

ReservoirSample()

Constructors
Constructor and Description
`ReservoirSample()`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`batchFinished()` Signify that this batch of input to the filter is finished.
`Capabilities`	`getCapabilities()` Returns the Capabilities of this filter.
`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.
`int`	`getSampleSize()` Gets the subsample size.
`java.lang.String`	`globalInfo()` Returns a string describing this filter
`boolean`	`input(Instance instance)` Input an instance for filtering.
`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`	`randomSeedTipText()` Returns the tip text for this property
`java.lang.String`	`sampleSizeTipText()` Returns the tip text for this property
`boolean`	`setInputFormat(Instances instanceInfo)` Sets the format of the input instances.
`void`	`setOptions(java.lang.String[] options)` Parses a given list of options.
`void`	`setRandomSeed(int newSeed)` Sets the random number seed.
`void`	`setSampleSize(int newSampleSize)` Sets the size of the subsample.

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
  - ReservoirSample
```
public ReservoirSample()
```
- Method Detail
  - globalInfo
```
public java.lang.String globalInfo()
```
    Returns a string describing this filter
    
    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 - number of instances
  (default 100)
```
    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.
  - sampleSizeTipText
```
public java.lang.String sampleSizeTipText()
```
    Returns the tip text for this property
    
    Returns:
    
    tip text for this property suitable for displaying in the explorer/experimenter gui
  - getSampleSize
```
public int getSampleSize()
```
    Gets the subsample size.
    
    Returns:
    
    the subsample size
  - setSampleSize
```
public void setSampleSize(int newSampleSize)
```
    Sets the size of the subsample.
    
    Parameters:
    
    newSampleSize - size of the subsample.
  - 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
  - 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

Class ReservoirSample

Constructor Summary

Method Summary

Methods inherited from class weka.filters.Filter

Methods inherited from class java.lang.Object

Constructor Detail

ReservoirSample

Method Detail

globalInfo

listOptions

setOptions

getOptions

randomSeedTipText

getRandomSeed

setRandomSeed

sampleSizeTipText

getSampleSize

setSampleSize

getCapabilities

setInputFormat

input

batchFinished

getRevision

main