gr.auth.ee.lcs.evaluators.ConfusionMatrixEvaluator.java Source code

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Here is the source code for gr.auth.ee.lcs.evaluators.ConfusionMatrixEvaluator.java

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/*
 *   Copyright (C) 2011 by Allamanis Miltiadis
 *
 *   Permission is hereby granted, free of charge, to any person obtaining a copy
 *   of this software and associated documentation files (the "Software"), to deal
 *   in the Software without restriction, including without limitation the rights
 *   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 *   copies of the Software, and to permit persons to whom the Software is
 *   furnished to do so, subject to the following conditions:
 *
 *   The above copyright notice and this permission notice shall be included in
 *   all copies or substantial portions of the Software.
 *
 *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 *   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 *   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 *   THE SOFTWARE.
 */
/**
 * 
 */
package gr.auth.ee.lcs.evaluators;

import gr.auth.ee.lcs.AbstractLearningClassifierSystem;
import gr.auth.ee.lcs.data.ClassifierTransformBridge;
import gr.auth.ee.lcs.data.ILCSMetric;
import weka.classifiers.evaluation.ConfusionMatrix;

/**
 * @author Miltos Allamanis
 * 
 */
public final class ConfusionMatrixEvaluator implements ILCSMetric {

    /**
     * A Weka confusion matrix.
     */
    private final ConfusionMatrix conf;

    /**
     * The LCS instance being used.
     */
    private final AbstractLearningClassifierSystem myLcs;

    /**
     * The instances.
     */
    private final double[][] instances;

    /**
     * Constructor for creating a confusion matrix.
     * 
     * @param classNames
     *            the class names
     * @param set
     *            the set of instances to be used for creating the confusion
     *            matrix
     * @param lcs
     *            the LCS instance used
     */
    public ConfusionMatrixEvaluator(final String[] classNames, final double[][] set,
            final AbstractLearningClassifierSystem lcs) {
        conf = new ConfusionMatrix(classNames);
        this.instances = set;
        myLcs = lcs;
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * gr.auth.ee.lcs.data.IEvaluator#evaluateSet(gr.auth.ee.lcs.classifiers
     * .ClassifierSet)
     */
    @Override
    public double getMetric(final AbstractLearningClassifierSystem theLcs) {
        final ClassifierTransformBridge bridge = myLcs.getClassifierTransformBridge();

        for (int i = 0; i < instances.length; i++) {
            final int[] classes = bridge.classify(theLcs.getRulePopulation(), instances[i]);
            if (classes == null)
                continue; // TODO: Use majority
            final int y = classes[0];
            final int x = bridge.getDataInstanceLabels(instances[i])[0];
            conf.setElement(x, y, conf.getElement(x, y) + 1);
        }

        System.out.println(conf);
        System.out.println("Error rate: " + conf.errorRate());

        return conf.errorRate();
    }

    public String getMetricName() {
        return "Confusion Matrix";
    }

}