weka.filters.supervised.attribute

## Class Discretize

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

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

      public class Discretize
      extends Filter
      implements SupervisedFilter, OptionHandler, WeightedInstancesHandler, TechnicalInformationHandler

  An instance filter that discretizes a range of numeric attributes in the dataset into nominal attributes. Discretization is by Fayyad & Irani's MDL method (the default).
  For more information, see:
  Usama M. Fayyad, Keki B. Irani: Multi-interval discretization of continuousvalued attributes for classification learning. In: Thirteenth International Joint Conference on Articial Intelligence, 1022-1027, 1993.
  Igor Kononenko: On Biases in Estimating Multi-Valued Attributes. In: 14th International Joint Conference on Articial Intelligence, 1034-1040, 1995.

  BibTeX:

       @inproceedings{Fayyad1993,
          author = {Usama M. Fayyad and Keki B. Irani},
          booktitle = {Thirteenth International Joint Conference on Articial Intelligence},
          pages = {1022-1027},
          publisher = {Morgan Kaufmann Publishers},
          title = {Multi-interval discretization of continuousvalued attributes for classification learning},
          volume = {2},
          year = {1993}
       }

       @inproceedings{Kononenko1995,
          author = {Igor Kononenko},
          booktitle = {14th International Joint Conference on Articial Intelligence},
          pages = {1034-1040},
          title = {On Biases in Estimating Multi-Valued Attributes},
          year = {1995},
          PS = {http://ai.fri.uni-lj.si/papers/kononenko95-ijcai.ps.gz}
       }

  Valid options are:

       -R <col1,col2-col4,...>
        Specifies list of columns to Discretize. First and last are valid indexes.
        (default none)

       -V
        Invert matching sense of column indexes.

       -D
        Output binary attributes for discretized attributes.

       -Y
        Use bin numbers rather than ranges for discretized attributes.

       -E
        Use better encoding of split point for MDL.

       -K
        Use Kononenko's MDL criterion.

       -precision <integer>
        Precision for bin boundary labels.
        (default = 6 decimal places).

  Version:
    $Revision: 10231 $
  Author:
    Len Trigg (trigg@cs.waikato.ac.nz), Eibe Frank (eibe@cs.waikato.ac.nz)
  See Also:
    Serialized Form

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `Discretize()` Constructor - initialises the filter

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `java.lang.String` | `attributeIndicesTipText()` Returns the tip text for this property
    `boolean` | `batchFinished()` Signifies that this batch of input to the filter is finished.
    `java.lang.String` | `binRangePrecisionTipText()` Returns the tip text for this property
    `java.lang.String` | `getAttributeIndices()` Gets the current range selection
    `int` | `getBinRangePrecision()` Get the precision for bin boundaries.
    `java.lang.String` | `getBinRangesString(int attributeIndex)` Gets the bin ranges string for an attribute
    `Capabilities` | `getCapabilities()` Returns the Capabilities of this filter.
    `double[]` | `getCutPoints(int attributeIndex)` Gets the cut points for an attribute
    `boolean` | `getInvertSelection()` Gets whether the supplied columns are to be removed or kept
    `boolean` | `getMakeBinary()` Gets whether binary attributes should be made for discretized ones.
    `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` | `getUseBetterEncoding()` Gets whether better encoding is to be used for MDL.
    `boolean` | `getUseBinNumbers()` Gets whether bin numbers rather than ranges should be used for discretized attributes.
    `boolean` | `getUseKononenko()` Gets whether Kononenko's MDL criterion is to be used.
    `java.lang.String` | `globalInfo()` Returns a string describing this filter
    `boolean` | `input(Instance instance)` Input an instance for filtering.
    `java.lang.String` | `invertSelectionTipText()` Returns the tip text for this property
    `java.util.Enumeration<Option>` | `listOptions()` Gets an enumeration describing the available options.
    `static void` | `main(java.lang.String[] argv)` Main method for testing this class.
    `java.lang.String` | `makeBinaryTipText()` Returns the tip text for this property
    `void` | `setAttributeIndices(java.lang.String rangeList)` Sets which attributes are to be Discretized (only numeric attributes among the selection will be Discretized).
    `void` | `setAttributeIndicesArray(int[] attributes)` Sets which attributes are to be Discretized (only numeric attributes among the selection will be Discretized).
    `void` | `setBinRangePrecision(int p)` Set the precision for bin boundaries.
    `boolean` | `setInputFormat(Instances instanceInfo)` Sets the format of the input instances.
    `void` | `setInvertSelection(boolean invert)` Sets whether selected columns should be removed or kept.
    `void` | `setMakeBinary(boolean makeBinary)` Sets whether binary attributes should be made for discretized ones.
    `void` | `setOptions(java.lang.String[] options)` Parses a given list of options.
    `void` | `setUseBetterEncoding(boolean useBetterEncoding)` Sets whether better encoding is to be used for MDL.
    `void` | `setUseBinNumbers(boolean useBinNumbers)` Sets whether bin numbers rather than ranges should be used for discretized attributes.
    `void` | `setUseKononenko(boolean useKon)` Sets whether Kononenko's MDL criterion is to be used.
    `java.lang.String` | `useBetterEncodingTipText()` Returns the tip text for this property
    `java.lang.String` | `useBinNumbersTipText()` Returns the tip text for this property
    `java.lang.String` | `useKononenkoTipText()` 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

    - #### Discretize

          public Discretize()

      Constructor - initialises the filter

  - ### Method Detail

    - #### listOptions

          public java.util.Enumeration<Option> listOptions()

      Gets 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:

           -R <col1,col2-col4,...>
            Specifies list of columns to Discretize. First and last are valid indexes.
            (default none)

           -V
            Invert matching sense of column indexes.

           -D
            Output binary attributes for discretized attributes.

           -Y
            Use bin numbers rather than ranges for discretized attributes.

           -E
            Use better encoding of split point for MDL.

           -K
            Use Kononenko's MDL criterion.

           -precision <integer>
            Precision for bin boundary labels.
            (default = 6 decimal places).

      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

    - #### 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. Ordinarily the instance is processed and made available for output immediately. Some filters require all 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 defined.

    - #### batchFinished

          public boolean batchFinished()

      Signifies 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

    - #### 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

    - #### binRangePrecisionTipText

          public java.lang.String binRangePrecisionTipText()

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

    - #### setBinRangePrecision

          public void setBinRangePrecision(int p)

      Set the precision for bin boundaries. Only affects the boundary values used in the labels for the converted attributes; internal cutpoints are at full double precision.
      Parameters:
        `p` - the precision for bin boundaries

    - #### getBinRangePrecision

          public int getBinRangePrecision()

      Get the precision for bin boundaries. Only affects the boundary values used in the labels for the converted attributes; internal cutpoints are at full double precision.
      Returns:
        the precision for bin boundaries

    - #### makeBinaryTipText

          public java.lang.String makeBinaryTipText()

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

    - #### getMakeBinary

          public boolean getMakeBinary()

      Gets whether binary attributes should be made for discretized ones.
      Returns:
        true if attributes will be binarized

    - #### setMakeBinary

          public void setMakeBinary(boolean makeBinary)

      Sets whether binary attributes should be made for discretized ones.
      Parameters:
        `makeBinary` - if binary attributes are to be made

    - #### useBinNumbersTipText

          public java.lang.String useBinNumbersTipText()

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

    - #### getUseBinNumbers

          public boolean getUseBinNumbers()

      Gets whether bin numbers rather than ranges should be used for discretized attributes.
      Returns:
        true if bin numbers should be used

    - #### setUseBinNumbers

          public void setUseBinNumbers(boolean useBinNumbers)

      Sets whether bin numbers rather than ranges should be used for discretized attributes.
      Parameters:
        `useBinNumbers` - if bin numbers should be used

    - #### useKononenkoTipText

          public java.lang.String useKononenkoTipText()

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

    - #### getUseKononenko

          public boolean getUseKononenko()

      Gets whether Kononenko's MDL criterion is to be used.
      Returns:
        true if Kononenko's criterion will be used.

    - #### setUseKononenko

          public void setUseKononenko(boolean useKon)

      Sets whether Kononenko's MDL criterion is to be used.
      Parameters:
        `useKon` - true if Kononenko's one is to be used

    - #### useBetterEncodingTipText

          public java.lang.String useBetterEncodingTipText()

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

    - #### getUseBetterEncoding

          public boolean getUseBetterEncoding()

      Gets whether better encoding is to be used for MDL.
      Returns:
        true if the better MDL encoding will be used

    - #### setUseBetterEncoding

          public void setUseBetterEncoding(boolean useBetterEncoding)

      Sets whether better encoding is to be used for MDL.
      Parameters:
        `useBetterEncoding` - true if better encoding to be used.

    - #### 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 the supplied columns are to be removed or kept
      Returns:
        true if the supplied columns will be kept

    - #### setInvertSelection

          public void setInvertSelection(boolean invert)

      Sets whether selected columns should be removed or kept. If true the selected columns are kept and unselected columns are deleted. If false selected columns are deleted and unselected columns are kept.
      Parameters:
        `invert` - the new invert setting

    - #### attributeIndicesTipText

          public java.lang.String attributeIndicesTipText()

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

    - #### getAttributeIndices

          public java.lang.String getAttributeIndices()

      Gets the current range selection
      Returns:
        a string containing a comma separated list of ranges

    - #### setAttributeIndices

          public void setAttributeIndices(java.lang.String rangeList)

      Sets which attributes are to be Discretized (only numeric attributes among the selection will be Discretized).
      Parameters:
        `rangeList` - a string representing the list of attributes. Since the string will typically come from a user, attributes are indexed from 1.
        eg: first-3,5,6-last
      Throws:
        `java.lang.IllegalArgumentException` - if an invalid range list is supplied

    - #### setAttributeIndicesArray

          public void setAttributeIndicesArray(int[] attributes)

      Sets which attributes are to be Discretized (only numeric attributes among the selection will be Discretized).
      Parameters:
        `attributes` - an array containing indexes of attributes to Discretize. Since the array will typically come from a program, attributes are indexed from 0.
      Throws:
        `java.lang.IllegalArgumentException` - if an invalid set of ranges is supplied

    - #### getCutPoints

          public double[] getCutPoints(int attributeIndex)

      Gets the cut points for an attribute
      Parameters:
        `attributeIndex` - the index (from 0) of the attribute to get the cut points of
      Returns:
        an array containing the cutpoints (or null if the attribute requested isn't being Discretized

    - #### getBinRangesString

          public java.lang.String getBinRangesString(int attributeIndex)

      Gets the bin ranges string for an attribute
      Parameters:
        `attributeIndex` - the index (from 0) of the attribute to get the bin ranges string of
      Returns:
        the bin ranges string (or null if the attribute requested has been discretized into only one interval.)

    - #### 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