Package weka.core.neighboursearch.balltrees

Class BottomUpConstructor

java.lang.Object
weka.core.neighboursearch.balltrees.BallTreeConstructor
weka.core.neighboursearch.balltrees.BottomUpConstructor
All Implemented Interfaces:
Serializable, OptionHandler, RevisionHandler, TechnicalInformationHandler
public class BottomUpConstructor extends BallTreeConstructor implements TechnicalInformationHandler
The class that constructs a ball tree bottom up.

BibTeX: 

 @techreport{Omohundro1989,
    author = {Stephen M. Omohundro},
    institution = {International Computer Science Institute},
    month = {December},
    number = {TR-89-063},
    title = {Five Balltree Construction Algorithms},
    year = {1989}
 }

Valid options are: 

 -N <value>
  Set maximum number of instances in a leaf node
  (default: 40)
 -R
  Set internal nodes' radius to the sum 
  of the child balls radii. So that it 
 contains the child balls.
Version:
$Revision: 8034 $
Author:
Ashraf M. Kibriya (amk14[at-the-rate]cs[dot]waikato[dot]ac[dot]nz)
See Also:

  • Constructor Details

    • BottomUpConstructor

      public BottomUpConstructor()
      Creates a new instance of BottomUpConstructor.

  • 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

    • 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

    • buildTree

      public BallNode buildTree() throws Exception
      Builds the ball tree bottom up.
      Specified by:
      buildTree in class BallTreeConstructor
      Returns:
      The root node of the tree.
      Throws:
      Exception - If there is problem building the tree.

    • addInstance

      public int[] addInstance(BallNode node, Instance inst) throws Exception
      Adds an instance to the ball tree.
      Specified by:
      addInstance in class BallTreeConstructor
      Parameters:
      node - The root node of the tree.
      inst - The instance to add to the tree.
      Returns:
      The new master index array after adding the instance.
      Throws:
      Exception - Always as BottomUpConstructor does not allow addition of instances after batch construction.

    • calcPivot

      public Instance calcPivot(weka.core.neighboursearch.balltrees.BottomUpConstructor.TempNode node1, weka.core.neighboursearch.balltrees.BottomUpConstructor.TempNode node2, Instances insts) throws Exception
      Calculates the centroid pivot of a node based on its two child nodes.
      Parameters:
      node1 - The first child node.
      node2 - The second child node.
      insts - The instance on which the tree is to be built.
      Returns:
      The centre/pivot of the node.
      Throws:
      Exception - If there is some problem calculating the centre/pivot of the node.

    • calcRadius

      public double calcRadius(weka.core.neighboursearch.balltrees.BottomUpConstructor.TempNode n1, weka.core.neighboursearch.balltrees.BottomUpConstructor.TempNode n2) throws Exception
      Calculates the radius of a node based on its two child nodes.
      Parameters:
      n1 - The first child node.
      n2 - The second child node.
      Returns:
      The calculated radius of the the node.
      Throws:
      Exception - If there is some problem in calculating the radius.

    • getRevision

      public String getRevision()
      Returns the revision string.
      Specified by:
      getRevision in interface RevisionHandler
      Overrides:
      getRevision in class BallTreeConstructor
      Returns:
      the revision