weka.filters.supervised.attribute

## Class NominalToBinary

- java.lang.Object
- - weka.filters.Filter
  - - weka.filters.supervised.attribute.NominalToBinary

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

      public class NominalToBinary
      extends Filter
      implements SupervisedFilter, OptionHandler, TechnicalInformationHandler

  Converts all nominal attributes into binary numeric attributes. An attribute with k values is transformed into k binary attributes if the class is nominal (using the one-attribute-per-value approach). Binary attributes are left binary, if option '-A' is not given.If the class is numeric, k - 1 new binary attributes are generated in the manner described in "Classification and Regression Trees" by Breiman et al. (i.e. taking the average class value associated with each attribute value into account)
  For more information, see:
  L. Breiman, J.H. Friedman, R.A. Olshen, C.J. Stone (1984). Classification and Regression Trees. Wadsworth Inc.

  BibTeX:

       @book{Breiman1984,
          author = {L. Breiman and J.H. Friedman and R.A. Olshen and C.J. Stone},
          publisher = {Wadsworth Inc},
          title = {Classification and Regression Trees},
          year = {1984},
          ISBN = {0412048418}
       }

  Valid options are:

       -N
        Sets if binary attributes are to be coded as nominal ones.

       -A
        For each nominal value a new attribute is created,
        not only if there are more than 2 values.

  Version:
    $Revision: 11872 $
  Author:
    Eibe Frank (eibe@cs.waikato.ac.nz)
  See Also:
    Serialized Form

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `NominalToBinary()`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `boolean` | `batchFinished()` Signify that this batch of input to the filter is finished.
    `java.lang.String` | `binaryAttributesNominalTipText()` Returns the tip text for this property
    `boolean` | `getBinaryAttributesNominal()` Gets if binary attributes are to be treated as nominal ones.
    `Capabilities` | `getCapabilities()` Returns the Capabilities of this filter.
    `java.lang.String[]` | `getOptions()` Gets the current settings of the filter.
    `java.lang.String` | `getRevision()` Returns the revision string.
    `TechnicalInformation` | `getTechnicalInformation()` Returns an instance of a TechnicalInformation object, containing detailed information about the technical background of this class, e.g., paper reference or book this class is based on.
    `boolean` | `getTransformAllValues()` Gets if all nominal values are turned into new attributes, not only if there are more than 2.
    `java.lang.String` | `globalInfo()` Returns a string describing this filter
    `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.
    `void` | `setBinaryAttributesNominal(boolean bool)` Sets if binary attributes are to be treates as nominal ones.
    `boolean` | `setInputFormat(Instances instanceInfo)` Sets the format of the input instances.
    `void` | `setOptions(java.lang.String[] options)` Parses a given list of options.
    `void` | `setTransformAllValues(boolean bool)` Sets whether all nominal values are transformed into new attributes, not just if there are more than 2.
    `java.lang.String` | `transformAllValuesTipText()` Returns the tip text for this property

    - ### 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

    - #### NominalToBinary

          public NominalToBinary()

  - ### Method Detail

    - #### globalInfo

          public java.lang.String globalInfo()

      Returns a string describing this filter
      Returns:
        a description of the filter suitable for displaying in the explorer/experimenter gui

    - #### getTechnicalInformation

          public TechnicalInformation getTechnicalInformation()

      Returns an instance of a TechnicalInformation object, containing detailed information about the technical background of this class, e.g., paper reference or book this class is based on.
      Specified by:
        `getTechnicalInformation` in interface `TechnicalInformationHandler`
      Returns:
        the technical information about this class

    - #### 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 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:
        `java.lang.IllegalStateException` - if no input structure has been defined

    - #### 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:

           -N
            Sets if binary attributes are to be coded as nominal ones.

           -A
            For each nominal value a new attribute is created,
            not only if there are more than 2 values.

      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

    - #### binaryAttributesNominalTipText

          public java.lang.String binaryAttributesNominalTipText()

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

    - #### getBinaryAttributesNominal

          public boolean getBinaryAttributesNominal()

      Gets if binary attributes are to be treated as nominal ones.
      Returns:
        true if binary attributes are to be treated as nominal ones

    - #### setBinaryAttributesNominal

          public void setBinaryAttributesNominal(boolean bool)

      Sets if binary attributes are to be treates as nominal ones.
      Parameters:
        `bool` - true if binary attributes are to be treated as nominal ones

    - #### transformAllValuesTipText

          public java.lang.String transformAllValuesTipText()

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

    - #### getTransformAllValues

          public boolean getTransformAllValues()

      Gets if all nominal values are turned into new attributes, not only if there are more than 2.
      Returns:
        true all nominal values are transformed into new attributes

    - #### setTransformAllValues

          public void setTransformAllValues(boolean bool)

      Sets whether all nominal values are transformed into new attributes, not just if there are more than 2.
      Parameters:
        `bool` - true if all nominal value are transformed into new attributes

    - #### 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