Package weka.core

Class InstanceComparator

java.lang.Object
weka.core.InstanceComparator
All Implemented Interfaces:
Serializable, Comparator, RevisionHandler

public class InstanceComparator extends Object implements Comparator, Serializable, RevisionHandler
A comparator for the Instance class. it can be used with or without the class label. Missing values are sorted at the beginning.
Can be used as comparator in the sorting and binary search algorithms of Arrays and Collections. Relational values are compared instance by instance with a nested InstanceComparator.
Version:
$Revision: 7988 $
Author:
FracPete (fracpete at cs dot waikato dot ac dot nz)
See Also:
  • Constructor Details

    • InstanceComparator

      public InstanceComparator()
      initializes the comparator and includes the class in the comparison
    • InstanceComparator

      public InstanceComparator(boolean includeClass)
      initializes the comparator
  • Method Details

    • setIncludeClass

      public void setIncludeClass(boolean includeClass)
      sets whether the class should be included (= TRUE) in the comparison
      Parameters:
      includeClass - whether to include the class in the comparison
    • getIncludeClass

      public boolean getIncludeClass()
      returns TRUE if the class is included in the comparison
    • compare

      public int compare(Object o1, Object o2)
      compares the two instances, returns -1 if o1 is smaller than o2, 0 if equal and +1 if greater. The method assumes that both instance objects have the same attributes, they don't have to belong to the same dataset.
      Specified by:
      compare in interface Comparator
      Parameters:
      o1 - the first instance to compare
      o2 - the second instance to compare
      Returns:
      returns -1 if o1 is smaller than o2, 0 if equal and +1 if greater
    • getRevision

      public String getRevision()
      Returns the revision string.
      Specified by:
      getRevision in interface RevisionHandler
      Returns:
      the revision
    • main

      public static void main(String[] args) throws Exception
      for testing only. takes an ARFF-filename as first argument to perform some tests.
      Throws:
      Exception