Package weka.filters.unsupervised.instance

Class 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 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.

      • 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

      • 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