weka.core.neighboursearch

Class NearestNeighbourSearch.NeighborList

java.lang.Object

weka.core.neighboursearch.NearestNeighbourSearch.NeighborList

All Implemented Interfaces:

RevisionHandler

Enclosing class:

NearestNeighbourSearch

protected class NearestNeighbourSearch.NeighborList
extends java.lang.Object
implements RevisionHandler

A class for a linked list to store the nearest k neighbours to an instance. We use a list so that we can take care of cases where multiple neighbours are the same distance away. i.e. the minimum length of the list is k.

Field Summary

Fields

Modifier and Type	Field and Description
protected NearestNeighbourSearch.NeighborNode	m_First The first node in the list.
protected NearestNeighbourSearch.NeighborNode	m_Last The last node in the list.
protected int	m_Length The number of nodes to attempt to maintain in the list.

Constructor Summary

Constructors

Constructor and Description
NeighborList(int length) Creates the neighborlist with a desired length.

Method Summary

Modifier and Type	Method and Description
int	currentLength() Gets the current length of the list.
NearestNeighbourSearch.NeighborNode	getFirst() returns the first element in the list.
NearestNeighbourSearch.NeighborNode	getLast() returns the last element in the list.
java.lang.String	getRevision() Returns the revision string.
void	insertSorted(double distance, Instance instance) Inserts an instance neighbor into the list, maintaining the list sorted by distance.
boolean	isEmpty() Gets whether the list is empty.
void	printList() Prints out the contents of the neighborlist.
void	pruneToK(int k) Prunes the list to contain the k nearest neighbors.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

m_First

protected NearestNeighbourSearch.NeighborNode m_First

The first node in the list.

m_Last

protected NearestNeighbourSearch.NeighborNode m_Last

The last node in the list.

m_Length

protected int m_Length

The number of nodes to attempt to maintain in the list.

Constructor Detail

NeighborList

public NeighborList(int length)

Creates the neighborlist with a desired length.

Parameters:

length - the length of list to attempt to maintain

Method Detail

isEmpty

public boolean isEmpty()

Gets whether the list is empty.

Returns:

true if list is empty

currentLength

public int currentLength()

Gets the current length of the list.

Returns:

the current length of the list

insertSorted

public void insertSorted(double distance,
                         Instance instance)

Inserts an instance neighbor into the list, maintaining the list sorted by distance.

Parameters:

distance - the distance to the instance

instance - the neighboring instance

pruneToK

public void pruneToK(int k)

Prunes the list to contain the k nearest neighbors. If there are multiple neighbors at the k'th distance, all will be kept.

Parameters:

k - the number of neighbors to keep in the list.

printList

public void printList()

Prints out the contents of the neighborlist.

getFirst

public NearestNeighbourSearch.NeighborNode getFirst()

returns the first element in the list.

Returns:

the first element

getLast

public NearestNeighbourSearch.NeighborNode getLast()

returns the last element in the list.

Returns:

the last element

getRevision

public java.lang.String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Returns:

the revision