weka.filters.unsupervised.instance

## Class Randomize

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

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

      public class Randomize
      extends Filter
      implements UnsupervisedFilter, OptionHandler

  Randomly shuffles the order of instances passed through it. The random number generator is reset with the seed value whenever a new set of instances is passed in.

  Valid options are:

       -S <num>
        Specify the random number seed (default 42)

  Version:
    $Revision: 10215 $
  Author:
    Len Trigg (trigg@cs.waikato.ac.nz)
  See Also:
    Serialized Form

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `Randomize()`

  - ### Method Summary

    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()` Get the random number generator seed value.
    `java.lang.String` | `getRevision()` Returns the revision string.
    `java.lang.String` | `globalInfo()` Returns a string describing this classifier
    `boolean` | `input(Instance instance)` Input an instance for filtering.
    `java.util.Enumeration<Option>` | `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
    `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 newRandomSeed)` Set the random number generator seed value.

    - ### Methods inherited from class weka.filters.Filter

      `batchFilterFile, debugTipText, doNotCheckCapabilitiesTipText, filterFile, getCapabilities, getDebug, getDoNotCheckCapabilities, getOutputFormat, isFirstBatchDone, isNewBatch, isOutputFormatDefined, makeCopies, makeCopy, mayRemoveInstanceAfterFirstBatchDone, numPendingOutput, output, outputPeek, runFilter, setDebug, setDoNotCheckCapabilities, toString, useFilter, wekaStaticWrapper`

    - ### Methods inherited from class java.lang.Object

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

- - ### Constructor Detail

    - #### Randomize

          public Randomize()

  - ### 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<Option> listOptions()

      Returns 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:

           -S <num>
            Specify the random number seed (default 42)

      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

    - #### 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()

      Get the random number generator seed value.
      Returns:
        random number generator seed value.

    - #### setRandomSeed

          public void setRandomSeed(int newRandomSeed)

      Set the random number generator seed value.
      Parameters:
        `newRandomSeed` - value to use as the random number generator seed.

    - #### 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 format cannot be processed

    - #### 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. Any subsequent instances filtered should be filtered based on setting obtained from the first batch (unless the setInputFormat has been re-assigned or new options have been set). This implementation randomizes all the instances received in the batch.
      Overrides:
        `batchFinished` in class `Filter`
      Returns:
        true if there are instances pending output
      Throws:
        `java.lang.IllegalStateException` - if no input format has been set.

    - #### 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