Package weka.filters.unsupervised.attribute

Class RemoveUseless

  • All Implemented Interfaces:
    java.io.Serializable, CapabilitiesHandler, OptionHandler, RevisionHandler, UnsupervisedFilter
    public class RemoveUseless
extends Filter
implements UnsupervisedFilter, OptionHandler
    This filter removes attributes that do not vary at all or that vary too much. All constant attributes are deleted automatically, along with any that exceed the maximum percentage of variance parameter. The maximum variance test is only applied to nominal attributes.

    Valid options are: 

     -M <max variance %>
  Maximum variance percentage allowed (default 99)
    Version:
    $Revision: 7470 $
    Author:
    Richard Kirkby (rkirkby@cs.waikato.ac.nz)
    See Also:
    Serialized Form

    • Constructor Detail

      • RemoveUseless

        public RemoveUseless()

    • Method Detail

      • 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 inputFormat can't be set successfully

      • input

        public boolean input​(Instance instance)
        Input an instance for filtering.
        Overrides:
        input in class Filter
        Parameters:
        instance - the input instance
        Returns:
        true if the filtered instance may now be collected with output().

      • batchFinished

        public boolean batchFinished()
                      throws java.lang.Exception
        Signify that this batch of input to the filter is finished.
        Overrides:
        batchFinished in class Filter
        Returns:
        true if there are instances pending output
        Throws:
        java.lang.Exception - if no input format defined

      • listOptions

        public java.util.Enumeration listOptions()
        Returns 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: 

         -M <max variance %>
  Maximum variance percentage allowed (default 99)
        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

      • 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

      • maximumVariancePercentageAllowedTipText

        public java.lang.String maximumVariancePercentageAllowedTipText()
        Returns the tip text for this property
        Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

      • setMaximumVariancePercentageAllowed

        public void setMaximumVariancePercentageAllowed​(double maxVariance)
        Sets the maximum variance attributes are allowed to have before they are deleted by the filter.
        Parameters:
        maxVariance - the maximum variance allowed, specified as a percentage

      • getMaximumVariancePercentageAllowed

        public double getMaximumVariancePercentageAllowed()
        Gets the maximum variance attributes are allowed to have before they are deleted by the filter.
        Returns:
        the maximum variance allowed, specified as a percentage

      • 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