it.poliba.sisinflab.simlib.featureSelection.methods.CHI.java Source code

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Here is the source code for it.poliba.sisinflab.simlib.featureSelection.methods.CHI.java

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/*
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package it.poliba.sisinflab.simlib.featureSelection.methods;

/**
 *
 * @author Corrado
 */
import java.io.File;
import java.io.PrintStream;
import java.util.Arrays;
import weka.core.Instances;
import weka.core.converters.ConverterUtils.DataSource;
import weka.attributeSelection.AttributeSelection;
import weka.attributeSelection.ChiSquaredAttributeEval;
import weka.attributeSelection.Ranker;

/**
 * This class use the featureSelection libary to implement Chi-Squared Test.
 */
public class CHI {

    public void execute(String dataset) {
        try {

            if (dataset.length() == 0)
                throw new IllegalArgumentException();
            // Load input dataset.
            DataSource source = new DataSource(dataset);
            System.out.println("Reading instances...");
            Instances data = source.getDataSet();

            // Performs a principal components analysis.
            ChiSquaredAttributeEval chiEvaluator = new ChiSquaredAttributeEval();

            // Ranking the attributes.
            Ranker ranker = new Ranker();
            // Specify the number of attributes to select from the ranked list.
            /*ranker.setThreshold(-1.7976931348623157E308);
            ranker.setNumToSelect(-1);
            ranker.setGenerateRanking(true);*/
            ranker.setNumToSelect(-1);

            AttributeSelection selector = new AttributeSelection();
            System.out.println("Selecting attributes...");
            selector.setSearch(ranker);
            selector.setEvaluator(chiEvaluator);
            selector.SelectAttributes(data);

            PrintStream o = new PrintStream(new File("data/" + "CHIResults" + ".txt"));
            System.setOut(o);
            System.out.println(Arrays.toString(selector.rankedAttributes()));
            System.out.println(Arrays.toString(selector.selectedAttributes()));
            //System.out.println(selector.CVResultsString());
            System.out.println(selector.toResultsString());

            System.out.println();

        } catch (IllegalArgumentException e) {
            System.err.println("Error");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}