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diff --git a/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/query/GenericRStarTreeKNNQuery.java b/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/query/GenericRStarTreeKNNQuery.java
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--- a/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/query/GenericRStarTreeKNNQuery.java
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@@ -1,243 +0,0 @@
-package de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.query;
-
-/*
- This file is part of ELKI:
- Environment for Developing KDD-Applications Supported by Index-Structures
-
- Copyright (C) 2013
- Ludwig-Maximilians-Universität München
- Lehr- und Forschungseinheit für Datenbanksysteme
- ELKI Development Team
-
- This program is free software: you can redistribute it and/or modify
- it under the terms of the GNU Affero General Public License as published by
- the Free Software Foundation, either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU Affero General Public License for more details.
-
- You should have received a copy of the GNU Affero General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Map.Entry;
-
-import de.lmu.ifi.dbs.elki.data.spatial.SpatialComparable;
-import de.lmu.ifi.dbs.elki.database.ids.ArrayDBIDs;
-import de.lmu.ifi.dbs.elki.database.ids.DBID;
-import de.lmu.ifi.dbs.elki.database.ids.DBIDIter;
-import de.lmu.ifi.dbs.elki.database.ids.DBIDUtil;
-import de.lmu.ifi.dbs.elki.database.ids.DBIDs;
-import de.lmu.ifi.dbs.elki.database.ids.ModifiableDBIDs;
-import de.lmu.ifi.dbs.elki.database.ids.distance.KNNHeap;
-import de.lmu.ifi.dbs.elki.database.ids.distance.KNNList;
-import de.lmu.ifi.dbs.elki.database.query.distance.SpatialDistanceQuery;
-import de.lmu.ifi.dbs.elki.database.query.knn.AbstractDistanceKNNQuery;
-import de.lmu.ifi.dbs.elki.distance.DistanceUtil;
-import de.lmu.ifi.dbs.elki.distance.distancefunction.SpatialPrimitiveDistanceFunction;
-import de.lmu.ifi.dbs.elki.distance.distancevalue.Distance;
-import de.lmu.ifi.dbs.elki.index.tree.DirectoryEntry;
-import de.lmu.ifi.dbs.elki.index.tree.LeafEntry;
-import de.lmu.ifi.dbs.elki.index.tree.query.GenericDistanceSearchCandidate;
-import de.lmu.ifi.dbs.elki.index.tree.spatial.SpatialEntry;
-import de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.AbstractRStarTree;
-import de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.AbstractRStarTreeNode;
-import de.lmu.ifi.dbs.elki.utilities.datastructures.heap.ComparableMinHeap;
-import de.lmu.ifi.dbs.elki.utilities.documentation.Reference;
-import de.lmu.ifi.dbs.elki.utilities.pairs.FCPair;
-
-/**
- * Instance of a KNN query for a particular spatial index.
- *
- * Reference:
- * <p>
- * G. R. Hjaltason, H. Samet<br />
- * Ranking in spatial databases<br />
- * In: 4th Symposium on Advances in Spatial Databases, SSD'95
- * </p>
- *
- * @author Erich Schubert
- *
- * @apiviz.uses AbstractRStarTree
- * @apiviz.uses SpatialPrimitiveDistanceFunction
- */
-@Reference(authors = "G. R. Hjaltason, H. Samet", title = "Ranking in spatial databases", booktitle = "Advances in Spatial Databases - 4th Symposium, SSD'95", url = "http://dx.doi.org/10.1007/3-540-60159-7_6")
-public class GenericRStarTreeKNNQuery<O extends SpatialComparable, D extends Distance<D>> extends AbstractDistanceKNNQuery<O, D> {
- /**
- * The index to use
- */
- protected final AbstractRStarTree<?, ?, ?> tree;
-
- /**
- * Spatial primitive distance function
- */
- protected final SpatialPrimitiveDistanceFunction<? super O, D> distanceFunction;
-
- /**
- * Constructor.
- *
- * @param tree Index to use
- * @param distanceQuery Distance query to use
- */
- public GenericRStarTreeKNNQuery(AbstractRStarTree<?, ?, ?> tree, SpatialDistanceQuery<O, D> distanceQuery) {
- super(distanceQuery);
- this.tree = tree;
- this.distanceFunction = distanceQuery.getDistanceFunction();
- }
-
- /**
- * Performs a batch knn query.
- *
- * @param node the node for which the query should be performed
- * @param knnLists a map containing the knn lists for each query objects
- */
- protected void batchNN(AbstractRStarTreeNode<?, ?> node, Map<DBID, KNNHeap<D>> knnLists) {
- if(node.isLeaf()) {
- for(int i = 0; i < node.getNumEntries(); i++) {
- SpatialEntry p = node.getEntry(i);
- for(Entry<DBID, KNNHeap<D>> ent : knnLists.entrySet()) {
- final DBID q = ent.getKey();
- final KNNHeap<D> knns_q = ent.getValue();
- D knn_q_maxDist = knns_q.getKNNDistance();
-
- DBID pid = ((LeafEntry) p).getDBID();
- // FIXME: objects are NOT accessible by DBID in a plain rtree context!
- D dist_pq = distanceQuery.distance(pid, q);
- tree.statistics.countDistanceCalculation();
- if(dist_pq.compareTo(knn_q_maxDist) <= 0) {
- knns_q.insert(dist_pq, pid);
- }
- }
- }
- }
- else {
- ModifiableDBIDs ids = DBIDUtil.newArray(knnLists.size());
- for(DBID id : knnLists.keySet()) {
- ids.add(id);
- }
- List<FCPair<D, SpatialEntry>> entries = getSortedEntries(node, ids);
- for(FCPair<D, SpatialEntry> distEntry : entries) {
- D minDist = distEntry.first;
- for(Entry<DBID, KNNHeap<D>> ent : knnLists.entrySet()) {
- final KNNHeap<D> knns_q = ent.getValue();
- D knn_q_maxDist = knns_q.getKNNDistance();
-
- if(minDist.compareTo(knn_q_maxDist) <= 0) {
- SpatialEntry entry = distEntry.second;
- AbstractRStarTreeNode<?, ?> child = tree.getNode(((DirectoryEntry) entry).getPageID().intValue());
- batchNN(child, knnLists);
- break;
- }
- }
- }
- }
- }
-
- /**
- * Sorts the entries of the specified node according to their minimum distance
- * to the specified objects.
- *
- * @param node the node
- * @param ids the id of the objects
- * @return a list of the sorted entries
- */
- protected List<FCPair<D, SpatialEntry>> getSortedEntries(AbstractRStarTreeNode<?, ?> node, DBIDs ids) {
- List<FCPair<D, SpatialEntry>> result = new ArrayList<>();
-
- for(int i = 0; i < node.getNumEntries(); i++) {
- SpatialEntry entry = node.getEntry(i);
- D minMinDist = distanceQuery.getDistanceFactory().infiniteDistance();
- for(DBIDIter iter = ids.iter(); iter.valid(); iter.advance()) {
- D minDist = distanceFunction.minDist(entry, relation.get(iter));
- tree.statistics.countDistanceCalculation();
- minMinDist = DistanceUtil.min(minDist, minMinDist);
- }
- result.add(new FCPair<>(minMinDist, entry));
- }
-
- Collections.sort(result);
- return result;
- }
-
- @Override
- public KNNList<D> getKNNForObject(O obj, int k) {
- final KNNHeap<D> knnList = DBIDUtil.newHeap(distanceFunction.getDistanceFactory(), k);
- final ComparableMinHeap<GenericDistanceSearchCandidate<D>> pq = new ComparableMinHeap<>(Math.min(knnList.getK() << 1, 20));
- tree.statistics.countKNNQuery();
-
- // push root
- pq.add(new GenericDistanceSearchCandidate<>(distanceFunction.getDistanceFactory().nullDistance(), tree.getRootID()));
- D maxDist = distanceFunction.getDistanceFactory().infiniteDistance();
-
- // search in tree
- while(!pq.isEmpty()) {
- GenericDistanceSearchCandidate<D> pqNode = pq.poll();
-
- if(pqNode.mindist.compareTo(maxDist) > 0) {
- break;
- }
- maxDist = expandNode(obj, knnList, pq, maxDist, pqNode.nodeID);
- }
- return knnList.toKNNList();
- }
-
- private D expandNode(O object, KNNHeap<D> knnList, final ComparableMinHeap<GenericDistanceSearchCandidate<D>> pq, D maxDist, final int nodeID) {
- AbstractRStarTreeNode<?, ?> node = tree.getNode(nodeID);
- // data node
- if(node.isLeaf()) {
- for(int i = 0; i < node.getNumEntries(); i++) {
- SpatialEntry entry = node.getEntry(i);
- D distance = distanceFunction.minDist(entry, object);
- tree.statistics.countDistanceCalculation();
- if(distance.compareTo(maxDist) <= 0) {
- knnList.insert(distance, ((LeafEntry) entry).getDBID());
- maxDist = knnList.getKNNDistance();
- }
- }
- }
- // directory node
- else {
- for(int i = 0; i < node.getNumEntries(); i++) {
- SpatialEntry entry = node.getEntry(i);
- D distance = distanceFunction.minDist(entry, object);
- tree.statistics.countDistanceCalculation();
- // Greedy expand, bypassing the queue
- if(distance.isNullDistance()) {
- expandNode(object, knnList, pq, maxDist, ((DirectoryEntry) entry).getPageID());
- }
- else {
- if(distance.compareTo(maxDist) <= 0) {
- pq.add(new GenericDistanceSearchCandidate<>(distance, ((DirectoryEntry) entry).getPageID()));
- }
- }
- }
- }
- return maxDist;
- }
-
- @Override
- public List<KNNList<D>> getKNNForBulkDBIDs(ArrayDBIDs ids, int k) {
- // While this works, it seems to be slow at least for large sets!
- final Map<DBID, KNNHeap<D>> knnLists = new HashMap<>(ids.size());
- for(DBIDIter iter = ids.iter(); iter.valid(); iter.advance()) {
- knnLists.put(DBIDUtil.deref(iter), DBIDUtil.newHeap(distanceFunction.getDistanceFactory(), k));
- }
-
- batchNN(tree.getRoot(), knnLists);
-
- List<KNNList<D>> result = new ArrayList<>();
- for(DBIDIter iter = ids.iter(); iter.valid(); iter.advance()) {
- tree.statistics.countKNNQuery();
- result.add(knnLists.get(DBIDUtil.deref(iter)).toKNNList());
- }
- return result;
- }
-}