1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
package de.lmu.ifi.dbs.elki.index.tree.metrical.mtreevariants.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 de.lmu.ifi.dbs.elki.database.ids.DBID;
import de.lmu.ifi.dbs.elki.database.ids.distance.DistanceDBIDList;
import de.lmu.ifi.dbs.elki.database.ids.generic.GenericDistanceDBIDList;
import de.lmu.ifi.dbs.elki.database.query.distance.DistanceQuery;
import de.lmu.ifi.dbs.elki.database.query.range.AbstractDistanceRangeQuery;
import de.lmu.ifi.dbs.elki.distance.distancevalue.NumberDistance;
import de.lmu.ifi.dbs.elki.index.tree.DirectoryEntry;
import de.lmu.ifi.dbs.elki.index.tree.metrical.mtreevariants.AbstractMTree;
import de.lmu.ifi.dbs.elki.index.tree.metrical.mtreevariants.AbstractMTreeNode;
import de.lmu.ifi.dbs.elki.index.tree.metrical.mtreevariants.MTreeEntry;
/**
* Instance of a range query for a particular spatial index.
*
* @author Erich Schubert
*
* @apiviz.uses AbstractMTree
*/
public class MetricalIndexRangeQuery<O, D extends NumberDistance<D, ?>> extends AbstractDistanceRangeQuery<O, D> {
/**
* The index to use
*/
protected final AbstractMTree<O, D, ?, ?, ?> index;
/**
* Constructor.
*
* @param index Index to use
* @param distanceQuery Distance query used
*/
public MetricalIndexRangeQuery(AbstractMTree<O, D, ?, ?, ?> index, DistanceQuery<O, D> distanceQuery) {
super(distanceQuery);
this.index = index;
}
/**
* Performs a range query on the specified subtree. It recursively traverses
* all paths from the specified node, which cannot be excluded from leading to
* qualifying objects.
*
* @param o_p the routing object of the specified node
* @param node the root of the subtree to be traversed
* @param q the id of the query object
* @param r_q the query range
* @param result the list holding the query results
*/
private void doRangeQuery(DBID o_p, AbstractMTreeNode<O, D, ?, ?> node, O q, D r_q, GenericDistanceDBIDList<D> result) {
double d1 = 0.;
if (o_p != null) {
d1 = distanceQuery.distance(o_p, q).doubleValue();
index.statistics.countDistanceCalculation();
}
if (!node.isLeaf()) {
for (int i = 0; i < node.getNumEntries(); i++) {
MTreeEntry entry = node.getEntry(i);
DBID o_r = entry.getRoutingObjectID();
double r_or = entry.getCoveringRadius();
double d2 = o_p != null ? entry.getParentDistance() : 0.;
double diff = Math.abs(d1 - d2);
double sum = r_q.doubleValue() + r_or;
if (diff <= sum) {
D d3 = distanceQuery.distance(o_r, q);
index.statistics.countDistanceCalculation();
if (d3.doubleValue() <= sum) {
AbstractMTreeNode<O, D, ?, ?> child = index.getNode(((DirectoryEntry) entry).getPageID());
doRangeQuery(o_r, child, q, r_q, result);
}
}
}
} else {
for (int i = 0; i < node.getNumEntries(); i++) {
MTreeEntry entry = node.getEntry(i);
DBID o_j = entry.getRoutingObjectID();
double d2 = o_p != null ? entry.getParentDistance() : 0.;
double diff = Math.abs(d1 - d2);
if (diff <= r_q.doubleValue()) {
D d3 = distanceQuery.distance(o_j, q);
index.statistics.countDistanceCalculation();
if (d3.compareTo(r_q) <= 0) {
result.add(d3, o_j);
}
}
}
}
}
@Override
public DistanceDBIDList<D> getRangeForObject(O obj, D range) {
final GenericDistanceDBIDList<D> result = new GenericDistanceDBIDList<>();
doRangeQuery(null, index.getRoot(), obj, range, result);
index.statistics.countRangeQuery();
// sort the result according to the distances
result.sort();
return result;
}
}
|
