Package weka.filters.unsupervised.attribute

Class Discretize

  • All Implemented Interfaces:
    java.io.Serializable, CapabilitiesHandler, 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.
    Version:
    $Revision: 8284 $
    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

      • Discretize

        public Discretize​(java.lang.String cols)
        Another constructor, sets the attribute indices immediately
        Parameters:
        cols - the attribute indices

    • Method Detail

      • 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.
        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

      • 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

      • 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.)

      • 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