de.lmu.ifi.dbs.elki.algorithm.outlier.lof

Class OnlineLOF.LOFKNNListener

java.lang.Object

de.lmu.ifi.dbs.elki.algorithm.outlier.lof.OnlineLOF.LOFKNNListener

All Implemented Interfaces:

KNNListener, EventListener

Enclosing class:

OnlineLOF<O>

private class OnlineLOF.LOFKNNListener
extends Object
implements KNNListener

Encapsulates a listener for changes of kNNs used in the online LOF algorithm.

Author:

Elke Achtert

Field Summary

Fields

Modifier and Type	Field and Description
private KNNChangeEvent	firstEventReceived Holds the first event of one of the both preprocessors.
private FlexibleLOF.LOFResult<O>	lofResult Holds the result of a former run of the LOF algorithm.

Constructor Summary

Constructors

Constructor and Description
OnlineLOF.LOFKNNListener(FlexibleLOF.LOFResult<O> lofResult) Constructs a listener for the LOF algorithm.

Method Summary

Methods

Modifier and Type	Method and Description
void	kNNsChanged(KNNChangeEvent e) Invoked after kNNs have been updated, inserted or removed in some way.
private void	kNNsChanged(KNNChangeEvent e1, KNNChangeEvent e2) Invoked after the events of both preprocessors have been received, i.e.
private void	kNNsInserted(DBIDs insertions, DBIDs updates1, DBIDs updates2, FlexibleLOF.LOFResult<O> lofResult) Invoked after kNNs have been inserted and updated, updates the result.
private void	kNNsRemoved(DBIDs deletions, DBIDs updates1, DBIDs updates2, FlexibleLOF.LOFResult<O> lofResult) Invoked after kNNs have been removed and updated, updates the result.
private ArrayModifiableDBIDs	mergeIDs(List<? extends DoubleDBIDList> queryResults, DBIDs... ids) Merges the ids of the query result with the specified ids.
private void	recomputeLOFs(DBIDs ids, FlexibleLOF.LOFResult<O> lofResult) Recomputes the lofs of the specified ids.

Methods inherited from class java.lang.Object

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

Field Detail

firstEventReceived

private KNNChangeEvent firstEventReceived

Holds the first event of one of the both preprocessors. The online algorithm is waiting until both events have been received, i.e. until both preprocessors are up to date.

lofResult

private FlexibleLOF.LOFResult<O> lofResult

Holds the result of a former run of the LOF algorithm.

Constructor Detail

OnlineLOF.LOFKNNListener

public OnlineLOF.LOFKNNListener(FlexibleLOF.LOFResult<O> lofResult)

Constructs a listener for the LOF algorithm.

Parameters:

lofResult - the result of a former run of the LOF algorithm

Method Detail

kNNsChanged

public void kNNsChanged(KNNChangeEvent e)

Description copied from interface: KNNListener

Invoked after kNNs have been updated, inserted or removed in some way.

Specified by:

kNNsChanged in interface KNNListener

Parameters:

e - the change event

kNNsChanged

private void kNNsChanged(KNNChangeEvent e1,
               KNNChangeEvent e2)

Invoked after the events of both preprocessors have been received, i.e. until both preprocessors are up to date.

Parameters:

e1 - the change event of the first preprocessor

e2 - the change event of the second preprocessor

kNNsInserted

private void kNNsInserted(DBIDs insertions,
                DBIDs updates1,
                DBIDs updates2,
                FlexibleLOF.LOFResult<O> lofResult)

Invoked after kNNs have been inserted and updated, updates the result.

Parameters:

insertions - the ids of the newly inserted neighborhoods

updates1 - the ids of the updated neighborhood w.r.t. the neighborhood distance function

updates2 - the ids of the updated neighborhood w.r.t. the reachability distance function

lofResult - the result of the former LOF run

kNNsRemoved

private void kNNsRemoved(DBIDs deletions,
               DBIDs updates1,
               DBIDs updates2,
               FlexibleLOF.LOFResult<O> lofResult)

Invoked after kNNs have been removed and updated, updates the result.

Parameters:

deletions - the ids of the removed neighborhoods

updates1 - the ids of the updated neighborhood w.r.t. the neighborhood distance function

updates2 - the ids of the updated neighborhood w.r.t. the reachability distance function

lofResult - the result of the former LOF run

mergeIDs

private ArrayModifiableDBIDs mergeIDs(List<? extends DoubleDBIDList> queryResults,
                            DBIDs... ids)

Merges the ids of the query result with the specified ids.

Parameters:

queryResults - the list of query results

ids - the list of ids

Returns:

a set containing the ids of the query result and the specified ids

recomputeLOFs

private void recomputeLOFs(DBIDs ids,
                 FlexibleLOF.LOFResult<O> lofResult)

Recomputes the lofs of the specified ids.

Parameters:

ids - the ids of the lofs to be recomputed

lofResult - the result of the former LOF run