Package elki.index.tree.spatial.rstarvariants.rdknn

Class RdKNNTree<O extends NumberVector>

java.lang.Object

elki.index.tree.IndexTree<N,E>

elki.index.tree.spatial.rstarvariants.AbstractRStarTree<N,E,S>

elki.index.tree.spatial.rstarvariants.NonFlatRStarTree<RdKNNNode,RdKNNEntry,RdkNNSettings>

elki.index.tree.spatial.rstarvariants.rdknn.RdKNNTree<O>

Type Parameters:

O - Object type

All Implemented Interfaces:

DistancePriorityIndex<O>, DynamicIndex, Index, KNNIndex<O>, RangeIndex<O>, RKNNIndex<O>

public class RdKNNTree<O extends NumberVector>
extends NonFlatRStarTree<RdKNNNode,RdKNNEntry,RdkNNSettings>
implements DistancePriorityIndex<O>, RKNNIndex<O>, DynamicIndex

RDkNNTree is a spatial index structure based on the concepts of the R*-Tree supporting efficient processing of reverse k nearest neighbor queries. The k-nn distance is stored in each entry of a node.

FIXME: currently does not have a RkNN implementation!

Since:

0.1

Author:

Elke Achtert

Nested Class Summary

Nested classes/interfaces inherited from class elki.index.tree.spatial.rstarvariants.AbstractRStarTree

AbstractRStarTree.Statistics

Field Summary

Fields

Modifier and Type	Field	Description
private SpatialDistanceQuery<O>	distanceQuery	The distance function.
protected KNNSearcher<DBIDRef>	knnQuery	Internal knn query object, for updating the rKNN.
private static Logging	LOG	The logger for this class.
private Relation<O>	relation	The relation we query.

Fields inherited from class elki.index.tree.spatial.rstarvariants.AbstractRStarTree

EXTRA_INTEGRITY_CHECKS, height, settings, statistics

Fields inherited from class elki.index.tree.IndexTree

dirCapacity, dirMinimum, initialized, leafCapacity, leafMinimum

Constructor Summary

Constructors

Constructor	Description
RdKNNTree(Relation<O> relation, PageFile<RdKNNNode> pagefile, RdkNNSettings settings)	Constructor.

Method Summary

Modifier and Type	Method	Description
private void	adjustKNNDistances(RdKNNEntry entry, ArrayDBIDs ids, double[] kdists)	Adjusts the knn distance in the subtree of the specified root entry.
protected void	bulkLoad(java.util.List<RdKNNEntry> entries)	Performs a bulk load on this RTree with the specified data.
private void	checkDistance(SpatialPrimitiveDistance<? super O> distance)	Throws an IllegalArgumentException if the specified distance function is not an instance of the distance function used by this index.
protected TreeIndexHeader	createHeader()	Creates a header for this index structure which is an instance of TreeIndexHeader.
protected RdKNNEntry	createNewDirectoryEntry(RdKNNNode node)	Creates a new directory entry representing the specified node.
protected RdKNNNode	createNewDirectoryNode()	Creates a new directory node with the specified capacity.
protected RdKNNLeafEntry	createNewLeafEntry(DBID id)
protected RdKNNNode	createNewLeafNode()	Creates a new leaf node with the specified capacity.
protected RdKNNEntry	createRootEntry()	Creates an entry representing the root node.
boolean	delete(DBIDRef id)	Deletes the specified object from this index.
void	deleteAll(DBIDs ids)	Deletes the specified objects from this index.
private void	doReverseKNN(RdKNNNode node, DBID oid, ModifiableDoubleDBIDList result)	Performs a reverse knn query in the specified subtree.
protected Logging	getLogger()	Get the (STATIC) logger for this class.
protected java.util.List<DoubleObjPair<RdKNNEntry>>	getSortedEntries(AbstractRStarTreeNode<?,?> node, SpatialComparable q, SpatialPrimitiveDistance<?> distance)	Sorts the entries of the specified node according to their minimum distance to the specified object.
void	initialize()	Initialize the tree if the page file already existed.
protected void	initializeCapacities(RdKNNEntry exampleLeaf)	Determines the maximum and minimum number of entries in a node.
void	insert(DBIDRef id)	Inserts the specified real vector object into this index.
void	insertAll(DBIDs ids)	Inserts the specified objects into this index.
KNNSearcher<O>	kNNByObject(DistanceQuery<O> distanceQuery, int maxk, int flags)	Get a KNN query object for the given distance query and k.
protected void	postDelete(RdKNNEntry entry)	Performs necessary operations after deleting the specified object.
protected void	preInsert(RdKNNEntry entry)	Performs necessary operations before inserting the specified entry.
private void	preInsert(RdKNNEntry q, RdKNNEntry nodeEntry, KNNHeap knns_q)	Adapts the knn distances before insertion of entry q.
PrioritySearcher<O>	priorityByObject(DistanceQuery<O> distanceQuery, double maxradius, int flags)	Get a priority search object.
RangeSearcher<O>	rangeByObject(DistanceQuery<O> distanceQuery, double maxradius, int flags)	Get a range query object for the given distance query and k.
DoubleDBIDList	reverseKNNQuery(DBID oid, int k, SpatialPrimitiveDistance<? super O> distance)
RKNNSearcher<DBIDRef>	rkNNByDBID(DistanceQuery<O> distanceQuery, int maxk, int flags)	Get a RKNN query object for the given distance query and k.
RKNNSearcher<O>	rkNNByObject(DistanceQuery<O> distanceQuery, int maxk, int flags)	Get a RKNN query object for the given distance query and k.

Methods inherited from class elki.index.tree.spatial.rstarvariants.NonFlatRStarTree

computeHeight, createEmptyRoot, hasOverflow, hasUnderflow

Methods inherited from class elki.index.tree.spatial.rstarvariants.AbstractRStarTree

adjustTree, canBulkLoad, choosePath, containedTest, createBulkLeafNodes, createNewRoot, deletePath, doExtraIntegrityChecks, findPathToObject, getHeight, getLeaves, initializeFromFile, insertEntry, insertLeaf, logStatistics, reInsert, setHeight, toString

Methods inherited from class elki.index.tree.IndexTree

deleteNode, getFile, getNode, getNode, getPageID, getPageSize, getRootEntry, getRootID, getRootPath, initialize, isRoot, writeNode

Methods inherited from class java.lang.Object

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

Methods inherited from interface elki.index.DistancePriorityIndex

priorityByDBID

Methods inherited from interface elki.index.Index

logStatistics

Methods inherited from interface elki.index.KNNIndex

kNNByDBID

Methods inherited from interface elki.index.RangeIndex

rangeByDBID

Field Detail

LOG

private static final Logging LOG

The logger for this class.

distanceQuery

private SpatialDistanceQuery<O extends NumberVector> distanceQuery

The distance function.

knnQuery

protected KNNSearcher<DBIDRef> knnQuery

Internal knn query object, for updating the rKNN.

relation

private Relation<O extends NumberVector> relation

The relation we query.

Constructor Detail

RdKNNTree

public RdKNNTree(Relation<O> relation,
                 PageFile<RdKNNNode> pagefile,
                 RdkNNSettings settings)

Constructor.

Parameters:

relation - Relation to index

pagefile - Data storage

settings - Tree settings

Method Detail

preInsert

protected void preInsert(RdKNNEntry entry)

Performs necessary operations before inserting the specified entry.

Overrides:

preInsert in class IndexTree<RdKNNNode,RdKNNEntry>

Parameters:

entry - the entry to be inserted

postDelete

protected void postDelete(RdKNNEntry entry)

Performs necessary operations after deleting the specified object.

Overrides:

postDelete in class IndexTree<RdKNNNode,RdKNNEntry>

Parameters:

entry - the entry that was removed

bulkLoad

protected void bulkLoad(java.util.List<RdKNNEntry> entries)

Performs a bulk load on this RTree with the specified data. Is called by the constructor and should be overwritten by subclasses if necessary.

Overrides:

bulkLoad in class NonFlatRStarTree<RdKNNNode,RdKNNEntry,RdkNNSettings>

Parameters:

entries - Entries to bulk load

reverseKNNQuery

public DoubleDBIDList reverseKNNQuery(DBID oid,
                                      int k,
                                      SpatialPrimitiveDistance<? super O> distance)

createHeader

protected TreeIndexHeader createHeader()

Description copied from class: IndexTree

Creates a header for this index structure which is an instance of TreeIndexHeader. Subclasses may need to overwrite this method if they need a more specialized header.

Overrides:

createHeader in class IndexTree<RdKNNNode,RdKNNEntry>

Returns:

a new header for this index structure

initializeCapacities

protected void initializeCapacities(RdKNNEntry exampleLeaf)

Description copied from class: IndexTree

Determines the maximum and minimum number of entries in a node.

Overrides:

initializeCapacities in class AbstractRStarTree<RdKNNNode,RdKNNEntry,RdkNNSettings>

Parameters:

exampleLeaf - an object that will be stored in the index

getSortedEntries

protected java.util.List<DoubleObjPair<RdKNNEntry>> getSortedEntries(AbstractRStarTreeNode<?,?> node,
                                                                     SpatialComparable q,
                                                                     SpatialPrimitiveDistance<?> distance)

Sorts the entries of the specified node according to their minimum distance to the specified object.

Parameters:

node - the node

q - the query object

distance - the distance function for computing the distances

Returns:

a list of the sorted entries

preInsert

private void preInsert(RdKNNEntry q,
                       RdKNNEntry nodeEntry,
                       KNNHeap knns_q)

Adapts the knn distances before insertion of entry q.

Parameters:

q - the entry to be inserted

nodeEntry - the entry representing the root of the current subtree

knns_q - the knns of q

doReverseKNN

private void doReverseKNN(RdKNNNode node,
                          DBID oid,
                          ModifiableDoubleDBIDList result)

Performs a reverse knn query in the specified subtree.

Parameters:

node - the root node of the current subtree

oid - the id of the object for which the rknn query is performed

result - the list containing the query results

adjustKNNDistances

private void adjustKNNDistances(RdKNNEntry entry,
                                ArrayDBIDs ids,
                                double[] kdists)

Adjusts the knn distance in the subtree of the specified root entry.

Parameters:

entry - the root entry of the current subtree

ids - Sorted list of IDs

kdists - knn distances

createNewLeafNode

protected RdKNNNode createNewLeafNode()

Creates a new leaf node with the specified capacity.

Specified by:

createNewLeafNode in class IndexTree<RdKNNNode,RdKNNEntry>

Returns:

a new leaf node

createNewDirectoryNode

protected RdKNNNode createNewDirectoryNode()

Creates a new directory node with the specified capacity.

Specified by:

createNewDirectoryNode in class IndexTree<RdKNNNode,RdKNNEntry>

Returns:

a new directory node

createNewDirectoryEntry

protected RdKNNEntry createNewDirectoryEntry(RdKNNNode node)

Creates a new directory entry representing the specified node.

Specified by:

createNewDirectoryEntry in class AbstractRStarTree<RdKNNNode,RdKNNEntry,RdkNNSettings>

Parameters:

node - the node to be represented by the new entry

Returns:

the newly created directory entry

createRootEntry

protected RdKNNEntry createRootEntry()

Creates an entry representing the root node.

Specified by:

createRootEntry in class IndexTree<RdKNNNode,RdKNNEntry>

Returns:

an entry representing the root node

checkDistance

private void checkDistance(SpatialPrimitiveDistance<? super O> distance)

Throws an IllegalArgumentException if the specified distance function is not an instance of the distance function used by this index.

Parameters:

distance - the distance function to be checked

Throws:

java.lang.IllegalArgumentException

createNewLeafEntry

protected RdKNNLeafEntry createNewLeafEntry(DBID id)

initialize

public void initialize()

Description copied from class: IndexTree

Initialize the tree if the page file already existed.

Specified by:

initialize in interface Index

Overrides:

initialize in class IndexTree<RdKNNNode,RdKNNEntry>

insert

public final void insert(DBIDRef id)

Inserts the specified real vector object into this index.

Specified by:

insert in interface DynamicIndex

Parameters:

id - the object id that was inserted

insertAll

public final void insertAll(DBIDs ids)

Inserts the specified objects into this index. If a bulk load mode is implemented, the objects are inserted in one bulk.

Specified by:

insertAll in interface DynamicIndex

Parameters:

ids - the objects to be inserted

delete

public final boolean delete(DBIDRef id)

Deletes the specified object from this index.

Specified by:

delete in interface DynamicIndex

Parameters:

id - Object to remove

Returns:

true if this index did contain the object with the specified id, false otherwise

deleteAll

public void deleteAll(DBIDs ids)

Description copied from interface: DynamicIndex

Deletes the specified objects from this index.

Specified by:

deleteAll in interface DynamicIndex

Parameters:

ids - Objects to remove

kNNByObject

public KNNSearcher<O> kNNByObject(DistanceQuery<O> distanceQuery,
                                  int maxk,
                                  int flags)

Description copied from interface: KNNIndex

Get a KNN query object for the given distance query and k.

This function MAY return null, when the given distance is not supported!

Specified by:

kNNByObject in interface DistancePriorityIndex<O extends NumberVector>

Specified by:

kNNByObject in interface KNNIndex<O extends NumberVector>

Parameters:

distanceQuery - Distance query

maxk - Maximum value of k

flags - Hints for the optimizer

Returns:

KNN Query object or null

rangeByObject

public RangeSearcher<O> rangeByObject(DistanceQuery<O> distanceQuery,
                                      double maxradius,
                                      int flags)

Description copied from interface: RangeIndex

Get a range query object for the given distance query and k.

This function MAY return null, when the given distance is not supported!

Specified by:

rangeByObject in interface DistancePriorityIndex<O extends NumberVector>

Specified by:

rangeByObject in interface RangeIndex<O extends NumberVector>

Parameters:

distanceQuery - Distance query

maxradius - Maximum range

flags - Hints for the optimizer

Returns:

KNN Query object or null

priorityByObject

public PrioritySearcher<O> priorityByObject(DistanceQuery<O> distanceQuery,
                                            double maxradius,
                                            int flags)

Description copied from interface: DistancePriorityIndex

Get a priority search object.

Specified by:

priorityByObject in interface DistancePriorityIndex<O extends NumberVector>

Parameters:

distanceQuery - Distance query

maxradius - Maximum search range (may be Double.POSITIVE_INFINITY

flags - Optimizer hints

Returns:

Priority searcher

rkNNByObject

public RKNNSearcher<O> rkNNByObject(DistanceQuery<O> distanceQuery,
                                    int maxk,
                                    int flags)

Description copied from interface: RKNNIndex

Get a RKNN query object for the given distance query and k.

This function MAY return null, when the given distance is not supported!

Specified by:

rkNNByObject in interface RKNNIndex<O extends NumberVector>

Parameters:

distanceQuery - Distance query

maxk - Maximum k for RkNN query

flags - Hints for the optimizer

Returns:

RKNN Query object or null

rkNNByDBID

public RKNNSearcher<DBIDRef> rkNNByDBID(DistanceQuery<O> distanceQuery,
                                        int maxk,
                                        int flags)

Description copied from interface: RKNNIndex

Get a RKNN query object for the given distance query and k.

This function MAY return null, when the given distance is not supported!

Specified by:

rkNNByDBID in interface RKNNIndex<O extends NumberVector>

Parameters:

distanceQuery - Distance query

maxk - Maximum k for RkNN query

flags - Hints for the optimizer

Returns:

RKNN Query object or null

getLogger

protected Logging getLogger()

Description copied from class: IndexTree

Get the (STATIC) logger for this class.

Specified by:

getLogger in class IndexTree<RdKNNNode,RdKNNEntry>

Returns:

the static logger