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.math.model.fit.residuals;
031
032import java.util.List;
033
034import org.openimaj.math.model.Model;
035import org.openimaj.util.pair.IndependentPair;
036
037/**
038 * Interface describing the computation of an error (the residuals) of a set of
039 * (independent and dependent) data points with respect to a model.
040 * 
041 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
042 * 
043 * @param <I>
044 *            type of independent data
045 * @param <D>
046 *            type of dependent data
047 * @param <M>
048 *            type of model
049 */
050public interface ResidualCalculator<I, D, M extends Model<I, D>> {
051        /**
052         * Set the current model being evaluated. This should be called every time
053         * the model has changed internally, as the {@link ResidualCalculator} might
054         * pre-cache variables based on the model for error computation.
055         * 
056         * @param model
057         *            the model
058         */
059        public void setModel(M model);
060
061        /**
062         * Compute the residual for a single point
063         * 
064         * @param data
065         *            the data
066         * @return the error
067         */
068        public double computeResidual(IndependentPair<I, D> data);
069
070        /**
071         * Compute the residual for a set of data points
072         * 
073         * @param data
074         *            the data
075         * @param residuals
076         *            the array to write the residuals into
077         */
078        public void computeResiduals(List<? extends IndependentPair<I, D>> data, double[] residuals);
079}