weka.clusterers.forOPTICSAndDBScan.Utils

Class UpdateQueue

java.lang.Object

weka.clusterers.forOPTICSAndDBScan.Utils.UpdateQueue

All Implemented Interfaces:

RevisionHandler

public class UpdateQueue
extends java.lang.Object
implements RevisionHandler

UpdateQueue.java
Authors: Rainer Holzmann, Zhanna Melnikova-Albrecht, Matthias Schubert
Date: Aug 27, 2004
Time: 5:36:35 PM
$ Revision 1.4 $

Version:

$Revision: 1.3 $

Author:

Matthias Schubert (schubert@dbs.ifi.lmu.de), Zhanna Melnikova-Albrecht (melnikov@cip.ifi.lmu.de), Rainer Holzmann (holzmann@cip.ifi.lmu.de)

Constructor Summary

Constructors

Constructor and Description
UpdateQueue() Creates a new PriorityQueue (backed on a binary heap) with the ability to efficiently update the priority of the stored objects in the heap.

Method Summary

Modifier and Type	Method and Description
void	add(double priority, java.lang.Object o, java.lang.String objectKey) Adds a new Object to the queue
double	getPriority(int index) Returns the priority for the object at the specified index
java.lang.String	getRevision() Returns the revision string.
boolean	hasNext() Tests, if the queue has some more elements left
UpdateQueueElement	next() Returns the element with the lowest priority
int	size() Returns the queue's size

Methods inherited from class java.lang.Object

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

Constructor Detail

UpdateQueue

public UpdateQueue()

Creates a new PriorityQueue (backed on a binary heap) with the ability to efficiently update the priority of the stored objects in the heap. The ascending (!) queue is dynamically growing and shrinking.

Method Detail

add

public void add(double priority,
                java.lang.Object o,
                java.lang.String objectKey)

Adds a new Object to the queue

Parameters:

priority - The priority associated with the object (in this case: the reachability-distance)

objectKey - The key for this object

o -

getPriority

public double getPriority(int index)

Returns the priority for the object at the specified index

Parameters:

index - the index of the object

Returns:

priority

size

public int size()

Returns the queue's size

Returns:

size

hasNext

public boolean hasNext()

Tests, if the queue has some more elements left

Returns:

true, if there are any elements left, else false

next

public UpdateQueueElement next()

Returns the element with the lowest priority

Returns:

next element

getRevision

public java.lang.String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Returns:

the revision