package de.lmu.ifi.dbs.elki.result.outlier;
/*
This file is part of ELKI:
Environment for Developing KDD-Applications Supported by Index-Structures
Copyright (C) 2012
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.Comparator;
import de.lmu.ifi.dbs.elki.database.ids.ArrayModifiableDBIDs;
import de.lmu.ifi.dbs.elki.database.ids.DBID;
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.relation.Relation;
import de.lmu.ifi.dbs.elki.result.OrderingResult;
import de.lmu.ifi.dbs.elki.utilities.iterator.IterableIterator;
import de.lmu.ifi.dbs.elki.utilities.iterator.IterableIteratorAdapter;
/**
* Ordering obtained from an outlier score.
*
* @author Erich Schubert
*
* @apiviz.uses Relation
*/
public class OrderingFromRelation implements OrderingResult {
/**
* Outlier scores.
*/
protected Relation<Double> scores;
/**
* Factor for ascending (+1) and descending (-1) ordering.
*/
protected int ascending = +1;
/**
* Constructor for outlier orderings
*
* @param scores outlier score result
* @param ascending Ascending when {@code true}, descending otherwise
*/
public OrderingFromRelation(Relation<Double> scores, boolean ascending) {
super();
this.scores = scores;
this.ascending = ascending ? +1 : -1;
}
/**
* Ascending constructor.
*
* @param scores
*/
public OrderingFromRelation(Relation<Double> scores) {
this(scores, true);
}
@Override
public DBIDs getDBIDs() {
return scores.getDBIDs();
}
@Override
public IterableIterator<DBID> iter(DBIDs ids) {
ArrayModifiableDBIDs sorted = DBIDUtil.newArray(ids);
sorted.sort(new ImpliedComparator());
return new IterableIteratorAdapter<DBID>(sorted);
}
@Override
public String getLongName() {
return scores.getLongName()+" Order";
}
@Override
public String getShortName() {
return scores.getShortName()+"_order";
}
/**
* Internal comparator, accessing the map to sort objects
*
* @author Erich Schubert
*
* @apiviz.exclude
*/
protected final class ImpliedComparator implements Comparator<DBID> {
@Override
public int compare(DBID id1, DBID id2) {
Double k1 = scores.get(id1);
Double k2 = scores.get(id2);
assert (k1 != null);
assert (k2 != null);
return ascending * k2.compareTo(k1);
}
}
}