Package weka.core.neighboursearch

Class NearestNeighbourSearch

java.lang.Object
weka.core.neighboursearch.NearestNeighbourSearch
All Implemented Interfaces:
Serializable, AdditionalMeasureProducer, OptionHandler, RevisionHandler
Direct Known Subclasses:
BallTree, CoverTree, FilteredNeighbourSearch, KDTree, LinearNNSearch
public abstract class NearestNeighbourSearch extends Object implements Serializable, OptionHandler, AdditionalMeasureProducer, RevisionHandler
Abstract class for nearest neighbour search. All algorithms (classes) that do nearest neighbour search should extend this class.
Version:
$Revision: 10203 $
Author:
Ashraf M. Kibriya (amk14[at-the-rate]cs[dot]waikato[dot]ac[dot]nz)
See Also:

  • Constructor Details

    • NearestNeighbourSearch

      public NearestNeighbourSearch()
      Constructor.

    • NearestNeighbourSearch

      public NearestNeighbourSearch(Instances insts)
      Constructor.
      Parameters:
      insts - The set of instances that constitute the neighbourhood.

  • Method Details

    • globalInfo

      public String globalInfo()
      Returns a string describing this nearest neighbour search algorithm.
      Returns:
      a description of the algorithm for displaying in the explorer/experimenter gui

    • listOptions

      public Enumeration<Option> 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(String[] options) throws Exception
      Parses a given list of options. Valid options are:
      Specified by:
      setOptions in interface OptionHandler
      Parameters:
      options - the list of options as an array of strings
      Throws:
      Exception - if an option is not supported

    • getOptions

      public String[] getOptions()
      Gets the current settings.
      Specified by:
      getOptions in interface OptionHandler
      Returns:
      an array of strings suitable for passing to setOptions()

    • distanceFunctionTipText

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

    • getDistanceFunction

      public DistanceFunction getDistanceFunction()
      returns the distance function currently in use.
      Returns:
      the distance function

    • setDistanceFunction

      public void setDistanceFunction(DistanceFunction df) throws Exception
      sets the distance function to use for nearest neighbour search.
      Parameters:
      df - the new distance function to use
      Throws:
      Exception - if instances cannot be processed

    • measurePerformanceTipText

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

    • getMeasurePerformance

      public boolean getMeasurePerformance()
      Gets whether performance statistics are being calculated or not.
      Returns:
      true if the measure performance is calculated

    • setMeasurePerformance

      public void setMeasurePerformance(boolean measurePerformance)
      Sets whether to calculate the performance statistics or not.
      Parameters:
      measurePerformance - if true then the performance is calculated

    • nearestNeighbour

      public abstract Instance nearestNeighbour(Instance target) throws Exception
      Returns the nearest instance in the current neighbourhood to the supplied instance.
      Parameters:
      target - The instance to find the nearest neighbour for.
      Returns:
      the nearest neighbor
      Throws:
      Exception - if the nearest neighbour could not be found.

    • kNearestNeighbours

      public abstract Instances kNearestNeighbours(Instance target, int k) throws Exception
      Returns k nearest instances in the current neighbourhood to the supplied instance.
      Parameters:
      target - The instance to find the k nearest neighbours for.
      k - The number of nearest neighbours to find.
      Returns:
      the k nearest neighbors
      Throws:
      Exception - if the neighbours could not be found.

    • getDistances

      public abstract double[] getDistances() throws Exception
      Returns the distances of the k nearest neighbours. The kNearestNeighbours or nearestNeighbour needs to be called first for this to work.
      Returns:
      the distances
      Throws:
      Exception - if called before calling kNearestNeighbours or nearestNeighbours.

    • update

      public abstract void update(Instance ins) throws Exception
      Updates the NearNeighbourSearch algorithm for the new added instance. P.S.: The method assumes the instance has already been added to the m_Instances object by the caller.
      Parameters:
      ins - the instance to add
      Throws:
      Exception - if updating fails

    • addInstanceInfo

      public void addInstanceInfo(Instance ins)
      Adds information from the given instance without modifying the datastructure a lot.
      Parameters:
      ins - the instance to add the information from

    • setInstances

      public void setInstances(Instances insts) throws Exception
      Sets the instances.
      Parameters:
      insts - the instances to use
      Throws:
      Exception - if setting fails

    • getInstances

      public Instances getInstances()
      returns the instances currently set.
      Returns:
      the current instances

    • getPerformanceStats

      public PerformanceStats getPerformanceStats()
      Gets the class object that contains the performance statistics of the search method.
      Returns:
      the performance statistics

    • enumerateMeasures

      public Enumeration<String> enumerateMeasures()
      Returns an enumeration of the additional measure names.
      Specified by:
      enumerateMeasures in interface AdditionalMeasureProducer
      Returns:
      an enumeration of the measure names

    • getMeasure

      public double getMeasure(String additionalMeasureName)
      Returns the value of the named measure.
      Specified by:
      getMeasure in interface AdditionalMeasureProducer
      Parameters:
      additionalMeasureName - the name of the measure to query for its value
      Returns:
      the value of the named measure
      Throws:
      IllegalArgumentException - if the named measure is not supported

    • combSort11

      public static void combSort11(double[] arrayToSort, int[] linkedArray)
      sorts the two given arrays.
      Parameters:
      arrayToSort - The array sorting should be based on.
      linkedArray - The array that should have the same ordering as arrayToSort.

    • quickSort

      public static void quickSort(double[] arrayToSort, double[] linkedArray, int left, int right)
      performs quicksort.
      Parameters:
      arrayToSort - the array to sort
      linkedArray - the linked array
      left - the first index of the subset
      right - the last index of the subset