Class Discretize

  • All Implemented Interfaces:
    java.io.Serializable, CapabilitiesHandler, 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.
     -E
      Use better encoding of split point for MDL.
     -K
      Use Kononenko's MDL criterion.
    Version:
    $Revision: 9090 $
    Author:
    Len Trigg (trigg@cs.waikato.ac.nz), Eibe Frank (eibe@cs.waikato.ac.nz)
    See Also:
    Serialized Form
    • Constructor Detail

      • Discretize

        public Discretize()
        Constructor - initialises the filter
    • Method Detail

      • listOptions

        public java.util.Enumeration listOptions()
        Gets 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:

         -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.
         -E
          Use better encoding of split point for MDL.
         -K
          Use Kononenko's MDL criterion.
        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
      • 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
      • 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
      • 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
      • 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