001/**
002 * Copyright (c) 2011, The University of Southampton and the individual contributors.
003 * All rights reserved.
004 *
005 * Redistribution and use in source and binary forms, with or without modification,
006 * are permitted provided that the following conditions are met:
007 *
008 *   *  Redistributions of source code must retain the above copyright notice,
009 *      this list of conditions and the following disclaimer.
010 *
011 *   *  Redistributions in binary form must reproduce the above copyright notice,
012 *      this list of conditions and the following disclaimer in the documentation
013 *      and/or other materials provided with the distribution.
014 *
015 *   *  Neither the name of the University of Southampton nor the names of its
016 *      contributors may be used to endorse or promote products derived from this
017 *      software without specific prior written permission.
018 *
019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
020 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
021 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
022 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
023 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
026 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
028 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
029 */
030package org.openimaj.ml.clustering.assignment;
031
032import org.openimaj.util.pair.IndependentPair;
033
034/**
035 * The {@link SoftAssigner} interface describes classes that assign a spatial
036 * point to multiple clusters, possibly with weighting.
037 *
038 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
039 *
040 * @param <DATATYPE>
041 *            the primitive array datatype which represents a centroid of this
042 *            cluster.
043 * @param <DISTANCES>
044 *            primitive array datatype for recording distances between points
045 *            and cluster centroids.
046 */
047public interface SoftAssigner<DATATYPE, DISTANCES> extends Assigner<DATATYPE> {
048        /**
049         * Assign data to clusters.
050         *
051         * @param data
052         *            the data.
053         * @return The cluster indices which the data was assigned to.
054         */
055        public int[][] assign(DATATYPE[] data);
056
057        /**
058         * Assign a single point to some clusters.
059         *
060         * @param data
061         *            datum to assign.
062         *
063         * @return the assigned cluster indices.
064         */
065        public int[] assign(DATATYPE data);
066
067        /**
068         * Assign data to clusters. The results are returned in the indices and
069         * distances arrays. The return arrays must have the same length as the data
070         * array.
071         * 
072         * @param data
073         *            the data.
074         * @param assignments
075         *            the cluster indices for each data point.
076         * @param weights
077         *            the weights to the for each cluster for each data point.
078         */
079        public void assignWeighted(DATATYPE[] data, int[][] assignments, DISTANCES[] weights);
080
081        /**
082         * Assign a single point to some clusters.
083         *
084         * @param data
085         *            point to assign.
086         *
087         * @return the assigned cluster indices and weights.
088         */
089        public IndependentPair<int[], DISTANCES> assignWeighted(DATATYPE data);
090
091        /**
092         * The number of clusters.
093         *
094         * @return The number of clusters or unique ids that can be generated.
095         */
096        public int size();
097}