weka.filters.unsupervised.attribute

## Class Discretize

- java.lang.Object
- - weka.filters.Filter
  - - weka.filters.unsupervised.attribute.PotentialClassIgnorer
    - - weka.filters.unsupervised.attribute.Discretize

- All Implemented Interfaces:
    java.io.Serializable, CapabilitiesHandler, CapabilitiesIgnorer, OptionHandler, RevisionHandler, WeightedInstancesHandler, UnsupervisedFilter
  Direct Known Subclasses:
    PKIDiscretize

      public class Discretize
      extends PotentialClassIgnorer
      implements UnsupervisedFilter, WeightedInstancesHandler

  An instance filter that discretizes a range of numeric attributes in the dataset into nominal attributes. Discretization is by simple binning. Skips the class attribute if set.

  Valid options are:

       -unset-class-temporarily
        Unsets the class index temporarily before the filter is
        applied to the data.
        (default: no)

       -B <num>
        Specifies the (maximum) number of bins to divide numeric attributes into.
        (default = 10)

       -M <num>
        Specifies the desired weight of instances per bin for
        equal-frequency binning. If this is set to a positive
        number then the -B option will be ignored.
        (default = -1)

       -F
        Use equal-frequency instead of equal-width discretization.

       -O
        Optimize number of bins using leave-one-out estimate
        of estimated entropy (for equal-width discretization).
        If this is set then the -B option will be ignored.

       -R <col1,col2-col4,...>
        Specifies list of columns to Discretize. First and last are valid indexes.
        (default: first-last)

       -V
        Invert matching sense of column indexes.

       -D
        Output binary attributes for discretized attributes.

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

  Version:
    $Revision: 10215 $
  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
    `Discretize(java.lang.String cols)` Another constructor, sets the attribute indices immediately

  - ### 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` | `binsTipText()` Returns the tip text for this property
    `java.lang.String` | `desiredWeightOfInstancesPerIntervalTipText()` Returns the tip text for this property
    `java.lang.String` | `findNumBinsTipText()` Returns the tip text for this property
    `java.lang.String` | `getAttributeIndices()` Gets the current range selection
    `java.lang.String` | `getBinRangesString(int attributeIndex)` Gets the bin ranges string for an attribute
    `int` | `getBins()` Gets the number of bins numeric attributes will be divided into
    `Capabilities` | `getCapabilities()` Returns the Capabilities of this filter.
    `double[]` | `getCutPoints(int attributeIndex)` Gets the cut points for an attribute
    `double` | `getDesiredWeightOfInstancesPerInterval()` Get the DesiredWeightOfInstancesPerInterval value.
    `boolean` | `getFindNumBins()` Get the value of FindNumBins.
    `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.
    `boolean` | `getUseBinNumbers()` Gets whether bin numbers rather than ranges should be used for discretized attributes.
    `boolean` | `getUseEqualFrequency()` Get the value of UseEqualFrequency.
    `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` | `setBins(int numBins)` Sets the number of bins to divide each selected numeric attribute into
    `void` | `setDesiredWeightOfInstancesPerInterval(double newDesiredNumber)` Set the DesiredWeightOfInstancesPerInterval value.
    `void` | `setFindNumBins(boolean newFindNumBins)` Set the value of FindNumBins.
    `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` | `setUseBinNumbers(boolean useBinNumbers)` Sets whether bin numbers rather than ranges should be used for discretized attributes.
    `void` | `setUseEqualFrequency(boolean newUseEqualFrequency)` Set the value of UseEqualFrequency.
    `java.lang.String` | `useBinNumbersTipText()` Returns the tip text for this property
    `java.lang.String` | `useEqualFrequencyTipText()` Returns the tip text for this property

    - ### Methods inherited from class weka.filters.unsupervised.attribute.PotentialClassIgnorer

      `getIgnoreClass, getOutputFormat, ignoreClassTipText, setIgnoreClass`

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

      `batchFilterFile, debugTipText, doNotCheckCapabilitiesTipText, filterFile, getCapabilities, getDebug, getDoNotCheckCapabilities, 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

    - #### Discretize

          public Discretize(java.lang.String cols)

      Another constructor, sets the attribute indices immediately
      Parameters:
        `cols` - the attribute indices

  - ### 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 `PotentialClassIgnorer`
      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:

           -unset-class-temporarily
            Unsets the class index temporarily before the filter is
            applied to the data.
            (default: no)

           -B <num>
            Specifies the (maximum) number of bins to divide numeric attributes into.
            (default = 10)

           -M <num>
            Specifies the desired weight of instances per bin for
            equal-frequency binning. If this is set to a positive
            number then the -B option will be ignored.
            (default = -1)

           -F
            Use equal-frequency instead of equal-width discretization.

           -O
            Optimize number of bins using leave-one-out estimate
            of estimated entropy (for equal-width discretization).
            If this is set then the -B option will be ignored.

           -R <col1,col2-col4,...>
            Specifies list of columns to Discretize. First and last are valid indexes.
            (default: first-last)

           -V
            Invert matching sense of column indexes.

           -D
            Output binary attributes for discretized attributes.

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

      Specified by:
        `setOptions` in interface `OptionHandler`
      Overrides:
        `setOptions` in class `PotentialClassIgnorer`
      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 `PotentialClassIgnorer`
      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 `PotentialClassIgnorer`
      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

    - #### findNumBinsTipText

          public java.lang.String findNumBinsTipText()

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

    - #### getFindNumBins

          public boolean getFindNumBins()

      Get the value of FindNumBins.
      Returns:
        Value of FindNumBins.

    - #### setFindNumBins

          public void setFindNumBins(boolean newFindNumBins)

      Set the value of FindNumBins.
      Parameters:
        `newFindNumBins` - Value to assign to FindNumBins.

    - #### 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

    - #### desiredWeightOfInstancesPerIntervalTipText

          public java.lang.String desiredWeightOfInstancesPerIntervalTipText()

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

    - #### getDesiredWeightOfInstancesPerInterval

          public double getDesiredWeightOfInstancesPerInterval()

      Get the DesiredWeightOfInstancesPerInterval value.
      Returns:
        the DesiredWeightOfInstancesPerInterval value.

    - #### setDesiredWeightOfInstancesPerInterval

          public void setDesiredWeightOfInstancesPerInterval(double newDesiredNumber)

      Set the DesiredWeightOfInstancesPerInterval value.
      Parameters:
        `newDesiredNumber` - The new DesiredNumber value.

    - #### useEqualFrequencyTipText

          public java.lang.String useEqualFrequencyTipText()

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

    - #### getUseEqualFrequency

          public boolean getUseEqualFrequency()

      Get the value of UseEqualFrequency.
      Returns:
        Value of UseEqualFrequency.

    - #### setUseEqualFrequency

          public void setUseEqualFrequency(boolean newUseEqualFrequency)

      Set the value of UseEqualFrequency.
      Parameters:
        `newUseEqualFrequency` - Value to assign to UseEqualFrequency.

    - #### binsTipText

          public java.lang.String binsTipText()

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

    - #### getBins

          public int getBins()

      Gets the number of bins numeric attributes will be divided into
      Returns:
        the number of bins.

    - #### setBins

          public void setBins(int numBins)

      Sets the number of bins to divide each selected numeric attribute into
      Parameters:
        `numBins` - the number of bins

    - #### 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 has been discretized into only one interval.)

    - #### 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