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ELKI - Main Module – Open-Source Data-Mining Framework with Index Acceleration

There is a newer version: 0.7.5

package de.lmu.ifi.dbs.elki.database.query.knn;

/*
 This file is part of ELKI:
 Environment for Developing KDD-Applications Supported by Index-Structures

 Copyright (C) 2015
 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 .
 */

import java.util.ArrayList;
import java.util.List;

import de.lmu.ifi.dbs.elki.database.ids.ArrayDBIDs;
import de.lmu.ifi.dbs.elki.database.ids.DBIDIter;
import de.lmu.ifi.dbs.elki.database.ids.DBIDRef;
import de.lmu.ifi.dbs.elki.database.ids.KNNList;
import de.lmu.ifi.dbs.elki.database.query.distance.DistanceQuery;
import de.lmu.ifi.dbs.elki.database.relation.Relation;

/**
 * Instance for the query on a particular database.
 * 
 * @author Erich Schubert
 * @since 0.4.0
 */
public abstract class AbstractDistanceKNNQuery implements KNNQuery {
  /**
   * The data to use for this query
   */
  final protected Relation relation;

  /**
   * Hold the distance function to be used.
   */
  final protected DistanceQuery distanceQuery;

  /**
   * Constructor.
   * 
   * @param distanceQuery Distance query used
   */
  public AbstractDistanceKNNQuery(DistanceQuery distanceQuery) {
    super();
    this.relation = distanceQuery.getRelation();
    this.distanceQuery = distanceQuery;
  }

  @Override
  public List getKNNForBulkDBIDs(ArrayDBIDs ids, int k) {
    // throw new
    // UnsupportedOperationException(ExceptionMessages.UNSUPPORTED_NOT_YET);
    // TODO: optimize
    List ret = new ArrayList<>(ids.size());
    for(DBIDIter iter = ids.iter(); iter.valid(); iter.advance()) {
      ret.add(getKNNForDBID(iter, k));
    }
    return ret;
  }

  @Override
  public KNNList getKNNForDBID(DBIDRef id, int k) {
    return getKNNForObject(relation.get(id), k);
  }

  @Override
  abstract public KNNList getKNNForObject(O obj, int k);
}