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.matrix.similarity.processor;
031
032import org.openimaj.math.matrix.similarity.SimilarityMatrix;
033
034/**
035 * A similarity matrix processor that sets all values
036 * less than a threshold to 0 and all other values to
037 * 1.
038 * 
039 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
040 *
041 */
042public class Threshold implements SimilarityMatrixProcessor {
043        protected double threshold;
044
045        /**
046         * Default constructor. 
047         * @param threshold the threshold
048         */
049        public Threshold(double threshold) {
050                this.threshold = threshold;
051        }
052        
053        @Override
054        public void process(SimilarityMatrix matrix) {
055                final int rows = matrix.getRowDimension();
056                final int cols = matrix.getColumnDimension();
057                final double[][] data = matrix.getArray(); 
058                
059                for (int r=0; r<rows; r++) {
060                        for (int c=0; c<cols; c++) {
061                                if (data[r][c] < threshold) {
062                                        data[r][c] = 0;
063                                } else {
064                                        data[r][c] = 1;
065                                }
066                        }
067                }
068        }
069
070}