Example usage for weka.core Instances classIndex

List of usage examples for weka.core Instances classIndex

Introduction

In this page you can find the example usage for weka.core Instances classIndex.

Prototype


publicint classIndex() 

Source Link

Document

Returns the class attribute's index.

Usage

From source file:Bilbo.java

License:Open Source License

/**
 * Returns a training set for a particular iteration.
 * /*from   w ww  .  j  ava2s.co  m*/
 * @param iteration the number of the iteration for the requested training set.
 * @return the training set for the supplied iteration number
 * @throws Exception if something goes wrong when generating a training set.
 */
@Override
protected synchronized Instances getTrainingSet(Instances p_data, int iteration) throws Exception {
    int bagSize = (int) (p_data.numInstances() * (m_BagSizePercent / 100.0));
    Instances bagData = null;
    Random r = new Random(m_Seed + iteration);

    // create the in-bag dataset
    if (m_CalcOutOfBag && p_data.classIndex() != -1) {
        m_inBag[iteration] = new boolean[p_data.numInstances()];
        bagData = p_data.resampleWithWeights(r, m_inBag[iteration], getRepresentCopiesUsingWeights());
    } else {
        bagData = p_data.resampleWithWeights(r, getRepresentCopiesUsingWeights());
        if (bagSize < p_data.numInstances()) {
            bagData.randomize(r);
            Instances newBagData = new Instances(bagData, 0, bagSize);
            bagData = newBagData;
        }
    }

    return bagData;
}

From source file:PrincipalComponents.java

License:Open Source License

/**
 * Return a summary of the analysis//from   w  w  w . ja v  a2 s .c  om
 *
 * @return a summary of the analysis.
 */
private String principalComponentsSummary() {
    StringBuffer result = new StringBuffer();
    double cumulative = 0.0;
    Instances output = null;
    int numVectors = 0;

    try {
        output = setOutputFormat();
        numVectors = (output.classIndex() < 0) ? output.numAttributes() : output.numAttributes() - 1;
    } catch (Exception ex) {
    }
    // tomorrow
    String corrCov = (m_center) ? "Covariance " : "Correlation ";
    result.append(corrCov + "matrix\n" + matrixToString(Matrices.getArray(m_correlation)) + "\n\n");
    result.append("eigenvalue\tproportion\tcumulative\n");
    for (int i = m_numAttribs - 1; i > (m_numAttribs - numVectors - 1); i--) {
        cumulative += m_eigenvalues[m_sortedEigens[i]];
        result.append(Utils.doubleToString(m_eigenvalues[m_sortedEigens[i]], 9, 5) + "\t"
                + Utils.doubleToString((m_eigenvalues[m_sortedEigens[i]] / m_sumOfEigenValues), 9, 5) + "\t"
                + Utils.doubleToString((cumulative / m_sumOfEigenValues), 9, 5) + "\t"
                + output.attribute(m_numAttribs - i - 1).name() + "\n");
    }

    result.append("\nEigenvectors\n");
    for (int j = 1; j <= numVectors; j++) {
        result.append(" V" + j + '\t');
    }
    result.append("\n");
    for (int j = 0; j < m_numAttribs; j++) {

        for (int i = m_numAttribs - 1; i > (m_numAttribs - numVectors - 1); i--) {
            result.append(Utils.doubleToString(m_eigenvectors[j][m_sortedEigens[i]], 7, 4) + "\t");
        }
        result.append(m_trainInstances.attribute(j).name() + '\n');
    }

    if (m_transBackToOriginal) {
        result.append("\nPC space transformed back to original space.\n"
                + "(Note: can't evaluate attributes in the original " + "space)\n");
    }
    return result.toString();
}

From source file:TextDirectoryLoader.java

License:Open Source License

/**
 * Return the full data set. If the structure hasn't yet been determined
 * by a call to getStructure then method should do so before processing
 * the rest of the data set./*w w  w  .  j  a  v a  2 s  . co  m*/
 *
 * @return the structure of the data set as an empty set of Instances
 * @throws IOException if there is no source or parsing fails
 */
public Instances getDataSet() throws IOException {
    if (getDirectory() == null)
        throw new IOException("No directory/source has been specified");

    String directoryPath = getDirectory().getAbsolutePath();
    FastVector classes = new FastVector();
    Enumeration enm = getStructure().classAttribute().enumerateValues();
    while (enm.hasMoreElements())
        classes.addElement(enm.nextElement());

    Instances data = getStructure();
    int fileCount = 0;
    for (int k = 0; k < classes.size(); k++) {
        String subdirPath = (String) classes.elementAt(k);
        File subdir = new File(directoryPath + File.separator + subdirPath);
        String[] files = subdir.list();
        for (int j = 0; j < files.length; j++) {
            try {
                fileCount++;
                if (getDebug())
                    System.err.println("processing " + fileCount + " : " + subdirPath + " : " + files[j]);

                double[] newInst = null;
                if (m_OutputFilename)
                    newInst = new double[3];
                else
                    newInst = new double[2];
                File txt = new File(directoryPath + File.separator + subdirPath + File.separator + files[j]);
                BufferedReader is;
                if (m_charSet == null || m_charSet.length() == 0) {
                    is = new BufferedReader(new InputStreamReader(new FileInputStream(txt)));
                } else {
                    is = new BufferedReader(new InputStreamReader(new FileInputStream(txt), m_charSet));
                }

                StringBuffer txtStr = new StringBuffer();
                int c;
                while ((c = is.read()) != -1) {
                    txtStr.append((char) c);
                }

                newInst[0] = (double) data.attribute(0).addStringValue(txtStr.toString());
                if (m_OutputFilename)
                    newInst[1] = (double) data.attribute(1)
                            .addStringValue(subdirPath + File.separator + files[j]);
                newInst[data.classIndex()] = (double) k;
                data.add(new Instance(1.0, newInst));
                is.close();
            } catch (Exception e) {
                System.err.println("failed to convert file: " + directoryPath + File.separator + subdirPath
                        + File.separator + files[j]);
            }
        }
    }

    return data;
}

From source file:FlexDMThread.java

License:Open Source License

public void run() {
    try {//www .  jav a2 s .c om
        //Get the data from the source

        FlexDM.getMainData.acquire();
        Instances data = dataset.getSource().getDataSet();
        FlexDM.getMainData.release();

        //Set class attribute if undefined
        if (data.classIndex() == -1) {
            data.setClassIndex(data.numAttributes() - 1);
        }

        //Process hyperparameters for classifier
        String temp = "";
        for (int i = 0; i < classifier.getNumParams(); i++) {
            temp += classifier.getParameter(i).getName();
            temp += " ";
            if (classifier.getParameter(i).getValue() != null) {
                temp += classifier.getParameter(i).getValue();
                temp += " ";
            }
        }

        String[] options = weka.core.Utils.splitOptions(temp);

        //Print to console- experiment is starting
        if (temp.equals("")) { //no parameters
            temp = "results_no_parameters";
            try {
                System.out.println("STARTING CLASSIFIER " + cNum + " - " + classifier.getName() + " on dataset "
                        + dataset.getName().substring(dataset.getName().lastIndexOf("\\") + 1)
                        + " with no parameters");
            } catch (Exception e) {
                System.out.println("STARTING CLASSIFIER " + cNum + " - " + classifier.getName() + " on dataset "
                        + dataset.getName() + " with no parameters");
            }
        } else { //parameters
            try {
                System.out.println("STARTING CLASSIFIER " + cNum + " - " + classifier.getName() + " on dataset "
                        + dataset.getName().substring(dataset.getName().lastIndexOf("\\") + 1)
                        + " with parameters " + temp);
            } catch (Exception e) {
                System.out.println("STARTING CLASSIFIER " + cNum + " - " + classifier.getName() + " on dataset "
                        + dataset.getName() + " with parameters " + temp);
            }
        }

        //Create classifier, setting parameters
        weka.classifiers.Classifier x = createObject(classifier.getName());
        x.setOptions(options);
        x.buildClassifier(data);

        //Process the test selection
        String[] tempTest = dataset.getTest().split("\\s");

        //Create evaluation object for training and testing classifiers
        Evaluation eval = new Evaluation(data);
        StringBuffer predictions = new StringBuffer();

        //Train and evaluate classifier
        if (tempTest[0].equals("testset")) { //specified test file
            //Build classifier
            x.buildClassifier(data);

            //Open test file, load data
            //DataSource testFile = new DataSource(dataset.getTest().substring(7).trim());
            // Instances testSet = testFile.getDataSet();
            FlexDM.getTestData.acquire();
            Instances testSet = dataset.getTestFile().getDataSet();
            FlexDM.getTestData.release();

            //Set class attribute if undefined
            if (testSet.classIndex() == -1) {
                testSet.setClassIndex(testSet.numAttributes() - 1);
            }

            //Evaluate model
            Object[] array = { predictions, new Range(), new Boolean(true) };
            eval.evaluateModel(x, testSet, array);
        } else if (tempTest[0].equals("xval")) { //Cross validation
            //Build classifier
            x.buildClassifier(data);

            //Cross validate
            eval.crossValidateModel(x, data, Integer.parseInt(tempTest[1]), new Random(1), predictions,
                    new Range(), true);
        } else if (tempTest[0].equals("leavexval")) { //Leave one out cross validation
            //Build classifier
            x.buildClassifier(data);

            //Cross validate
            eval.crossValidateModel(x, data, data.numInstances() - 1, new Random(1), predictions, new Range(),
                    true);
        } else if (tempTest[0].equals("percent")) { //Percentage split of single data set
            //Set training and test sizes from percentage
            int trainSize = (int) Math.round(data.numInstances() * Double.parseDouble(tempTest[1]));
            int testSize = data.numInstances() - trainSize;

            //Load specified data
            Instances train = new Instances(data, 0, trainSize);
            Instances testSet = new Instances(data, trainSize, testSize);

            //Build classifier
            x.buildClassifier(train);

            //Train and evaluate model
            Object[] array = { predictions, new Range(), new Boolean(true) };
            eval.evaluateModel(x, testSet, array);
        } else { //Evaluate on training data
            //Test and evaluate model
            Object[] array = { predictions, new Range(), new Boolean(true) };
            eval.evaluateModel(x, data, array);
        }

        //create datafile for results
        String filename = dataset.getDir() + "/" + classifier.getDirName() + "/" + temp + ".txt";
        PrintWriter writer = new PrintWriter(filename, "UTF-8");

        //Print classifier, dataset, parameters info to file
        try {
            writer.println("CLASSIFIER: " + classifier.getName() + "\n DATASET: " + dataset.getName()
                    + "\n PARAMETERS: " + temp);
        } catch (Exception e) {
            writer.println("CLASSIFIER: " + classifier.getName() + "\n DATASET: " + dataset.getName()
                    + "\n PARAMETERS: " + temp);
        }

        //Add evaluation string to file
        writer.println(eval.toSummaryString());
        //Process result options
        if (checkResults("stats")) { //Classifier statistics
            writer.println(eval.toClassDetailsString());
        }
        if (checkResults("model")) { //The model
            writer.println(x.toString());
        }
        if (checkResults("matrix")) { //Confusion matrix
            writer.println(eval.toMatrixString());
        }
        if (checkResults("entropy")) { //Entropy statistics
            //Set options req'd to get the entropy stats
            String[] opt = new String[4];
            opt[0] = "-t";
            opt[1] = dataset.getName();
            opt[2] = "-k";
            opt[3] = "-v";

            //Evaluate model
            String entropy = Evaluation.evaluateModel(x, opt);

            //Grab the relevant info from the results, print to file
            entropy = entropy.substring(entropy.indexOf("=== Stratified cross-validation ===") + 35,
                    entropy.indexOf("=== Confusion Matrix ==="));
            writer.println("=== Entropy Statistics ===");
            writer.println(entropy);
        }
        if (checkResults("predictions")) { //The models predictions
            writer.println("=== Predictions ===\n");
            if (!dataset.getTest().contains("xval")) { //print header of predictions table if req'd
                writer.println(" inst#     actual  predicted error distribution ()");
            }
            writer.println(predictions.toString()); //print predictions to file
        }

        writer.close();

        //Summary file is semaphore controlled to ensure quality
        try { //get a permit
              //grab the summary file, write the classifiers details to it
            FlexDM.writeFile.acquire();
            PrintWriter p = new PrintWriter(new FileWriter(summary, true));
            if (temp.equals("results_no_parameters")) { //change output based on parameters
                temp = temp.substring(8);
            }

            //write percent correct, classifier name, dataset name to summary file
            p.write(dataset.getName() + ", " + classifier.getName() + ", " + temp + ", " + eval.correct() + ", "
                    + eval.incorrect() + ", " + eval.unclassified() + ", " + eval.pctCorrect() + ", "
                    + eval.pctIncorrect() + ", " + eval.pctUnclassified() + ", " + eval.kappa() + ", "
                    + eval.meanAbsoluteError() + ", " + eval.rootMeanSquaredError() + ", "
                    + eval.relativeAbsoluteError() + ", " + eval.rootRelativeSquaredError() + ", "
                    + eval.SFPriorEntropy() + ", " + eval.SFSchemeEntropy() + ", " + eval.SFEntropyGain() + ", "
                    + eval.SFMeanPriorEntropy() + ", " + eval.SFMeanSchemeEntropy() + ", "
                    + eval.SFMeanEntropyGain() + ", " + eval.KBInformation() + ", " + eval.KBMeanInformation()
                    + ", " + eval.KBRelativeInformation() + ", " + eval.weightedTruePositiveRate() + ", "
                    + eval.weightedFalsePositiveRate() + ", " + eval.weightedTrueNegativeRate() + ", "
                    + eval.weightedFalseNegativeRate() + ", " + eval.weightedPrecision() + ", "
                    + eval.weightedRecall() + ", " + eval.weightedFMeasure() + ", "
                    + eval.weightedAreaUnderROC() + "\n");
            p.close();

            //release semaphore
            FlexDM.writeFile.release();
        } catch (InterruptedException e) { //bad things happened
            System.err.println("FATAL ERROR OCCURRED: Classifier: " + cNum + " - " + classifier.getName()
                    + " on dataset " + dataset.getName());
        }

        //output we have successfully finished processing classifier
        if (temp.equals("no_parameters")) { //no parameters
            try {
                System.out.println("FINISHED CLASSIFIER " + cNum + " - " + classifier.getName() + " on dataset "
                        + dataset.getName().substring(dataset.getName().lastIndexOf("\\") + 1)
                        + " with no parameters");
            } catch (Exception e) {
                System.out.println("FINISHED CLASSIFIER " + cNum + " - " + classifier.getName() + " on dataset "
                        + dataset.getName() + " with no parameters");
            }
        } else { //with parameters
            try {
                System.out.println("FINISHED CLASSIFIER " + cNum + " - " + classifier.getName() + " on dataset "
                        + dataset.getName().substring(dataset.getName().lastIndexOf("\\") + 1)
                        + " with parameters " + temp);
            } catch (Exception e) {
                System.out.println("FINISHED CLASSIFIER " + cNum + " - " + classifier.getName() + " on dataset "
                        + dataset.getName() + " with parameters " + temp);
            }
        }

        try { //get a permit
              //grab the log file, write the classifiers details to it
            FlexDM.writeLog.acquire();
            PrintWriter p = new PrintWriter(new FileWriter(log, true));

            Date date = new Date();
            Format formatter = new SimpleDateFormat("dd/MM/YYYY HH:mm:ss");
            //formatter.format(date)

            if (temp.equals("results_no_parameters")) { //change output based on parameters
                temp = temp.substring(8);
            }

            //write details to log file
            p.write(dataset.getName() + ", " + dataset.getTest() + ", \"" + dataset.getResult_string() + "\", "
                    + classifier.getName() + ", " + temp + ", " + formatter.format(date) + "\n");
            p.close();

            //release semaphore
            FlexDM.writeLog.release();
        } catch (InterruptedException e) { //bad things happened
            System.err.println("FATAL ERROR OCCURRED: Classifier: " + cNum + " - " + classifier.getName()
                    + " on dataset " + dataset.getName());
        }

        s.release();

    } catch (Exception e) {
        //an error occurred
        System.err.println("FATAL ERROR OCCURRED: " + e.toString() + "\nClassifier: " + cNum + " - "
                + classifier.getName() + " on dataset " + dataset.getName());
        s.release();
    }

}

From source file:REPTree.java

License:Open Source License

/**
 * Builds classifier.//w w w.j  ava2 s .  com
 * 
 * @param data the data to train with
 * @throws Exception if building fails
 */
public void buildClassifier(Instances data) throws Exception {

    // can classifier handle the data?
    getCapabilities().testWithFail(data);

    // remove instances with missing class
    data = new Instances(data);
    data.deleteWithMissingClass();

    Random random = new Random(m_Seed);

    m_zeroR = null;
    if (data.numAttributes() == 1) {
        m_zeroR = new ZeroR();
        m_zeroR.buildClassifier(data);
        return;
    }

    // Randomize and stratify
    data.randomize(random);
    if (data.classAttribute().isNominal()) {
        data.stratify(m_NumFolds);
    }

    // Split data into training and pruning set
    Instances train = null;
    Instances prune = null;
    if (!m_NoPruning) {
        train = data.trainCV(m_NumFolds, 0, random);
        prune = data.testCV(m_NumFolds, 0);
    } else {
        train = data;
    }

    // Create array of sorted indices and weights
    int[][][] sortedIndices = new int[1][train.numAttributes()][0];
    double[][][] weights = new double[1][train.numAttributes()][0];
    double[] vals = new double[train.numInstances()];
    for (int j = 0; j < train.numAttributes(); j++) {
        if (j != train.classIndex()) {
            weights[0][j] = new double[train.numInstances()];
            if (train.attribute(j).isNominal()) {

                // Handling nominal attributes. Putting indices of
                // instances with missing values at the end.
                sortedIndices[0][j] = new int[train.numInstances()];
                int count = 0;
                for (int i = 0; i < train.numInstances(); i++) {
                    Instance inst = train.instance(i);
                    if (!inst.isMissing(j)) {
                        sortedIndices[0][j][count] = i;
                        weights[0][j][count] = inst.weight();
                        count++;
                    }
                }
                for (int i = 0; i < train.numInstances(); i++) {
                    Instance inst = train.instance(i);
                    if (inst.isMissing(j)) {
                        sortedIndices[0][j][count] = i;
                        weights[0][j][count] = inst.weight();
                        count++;
                    }
                }
            } else {

                // Sorted indices are computed for numeric attributes
                for (int i = 0; i < train.numInstances(); i++) {
                    Instance inst = train.instance(i);
                    vals[i] = inst.value(j);
                }
                sortedIndices[0][j] = Utils.sort(vals);
                for (int i = 0; i < train.numInstances(); i++) {
                    weights[0][j][i] = train.instance(sortedIndices[0][j][i]).weight();
                }
            }
        }
    }

    // Compute initial class counts
    double[] classProbs = new double[train.numClasses()];
    double totalWeight = 0, totalSumSquared = 0;
    for (int i = 0; i < train.numInstances(); i++) {
        Instance inst = train.instance(i);
        if (data.classAttribute().isNominal()) {
            classProbs[(int) inst.classValue()] += inst.weight();
            totalWeight += inst.weight();
        } else {
            classProbs[0] += inst.classValue() * inst.weight();
            totalSumSquared += inst.classValue() * inst.classValue() * inst.weight();
            totalWeight += inst.weight();
        }
    }
    m_Tree = new Tree();
    double trainVariance = 0;
    if (data.classAttribute().isNumeric()) {
        trainVariance = m_Tree.singleVariance(classProbs[0], totalSumSquared, totalWeight) / totalWeight;
        classProbs[0] /= totalWeight;
    }

    // Build tree
    m_Tree.buildTree(sortedIndices, weights, train, totalWeight, classProbs, new Instances(train, 0), m_MinNum,
            m_MinVarianceProp * trainVariance, 0, m_MaxDepth);

    // Insert pruning data and perform reduced error pruning
    if (!m_NoPruning) {
        m_Tree.insertHoldOutSet(prune);
        m_Tree.reducedErrorPrune();
        m_Tree.backfitHoldOutSet();
    }
}

From source file:homemadeWEKA.java

public static Instances loadData(String filename) {

    Instances data = null;
    try {/*  w  ww  . j  a va 2s  .c  o m*/
        data = DataSource.read(filename);
        if (data.classIndex() == -1)
            data.setClassIndex(data.numAttributes() - 1);
    } catch (Exception ex) {
        Logger.getLogger(homemadeWEKA.class.getName()).log(Level.SEVERE, null, ex);
    }

    return data;
}

From source file:RunExhaustiveSearch.java

License:Open Source License

public static void main(String[] arg) throws Exception {
    // Load data.
    ///* ww w  .java 2  s .com*/
    System.out.println("\nLoading sample file...");
    DataSource source = new DataSource(arg[0]);
    Instances data = source.getDataSet();

    if (data.classIndex() == -1)
        data.setClassIndex(data.numAttributes() - 1);

    int n = Integer.parseInt(arg[1]);

    System.out.println("Instance with " + n + " features!");
    System.out.println("\nRunning ES algorithm with CFS cost function...");

    // Run feature selection algorithm ES using CFS cost function.
    //
    runAttributeSelection(data, n);
}

From source file:REPRandomTree.java

License:Open Source License

/**
 * Builds classifier.//from  w  w w. jav a2  s .co m
 * 
 * @param data the data to train with
 * @throws Exception if building fails
 */
public void buildClassifier(Instances data) throws Exception {

    // can classifier handle the data?
    getCapabilities().testWithFail(data);

    // remove instances with missing class
    data = new Instances(data);
    data.deleteWithMissingClass();

    Random random = new Random(m_Seed);

    m_zeroR = null;
    if (data.numAttributes() == 1) {
        m_zeroR = new ZeroR();
        m_zeroR.buildClassifier(data);
        return;
    }

    // Randomize and stratify
    data.randomize(random);
    if (data.classAttribute().isNominal()) {
        data.stratify(m_NumFolds);
    }

    // Split data into training and pruning set
    Instances train = null;
    Instances prune = null;
    if (!m_NoPruning) {
        train = data.trainCV(m_NumFolds, 0, random);
        prune = data.testCV(m_NumFolds, 0);
    } else {
        train = data;
    }

    // Create array of sorted indices and weights
    int[][][] sortedIndices = new int[1][train.numAttributes()][0];
    double[][][] weights = new double[1][train.numAttributes()][0];
    double[] vals = new double[train.numInstances()];
    for (int j = 0; j < train.numAttributes(); j++) {
        if (j != train.classIndex()) {
            weights[0][j] = new double[train.numInstances()];
            if (train.attribute(j).isNominal()) {

                // Handling nominal attributes. Putting indices of
                // instances with missing values at the end.
                sortedIndices[0][j] = new int[train.numInstances()];
                int count = 0;
                for (int i = 0; i < train.numInstances(); i++) {
                    Instance inst = train.instance(i);
                    if (!inst.isMissing(j)) {
                        sortedIndices[0][j][count] = i;
                        weights[0][j][count] = inst.weight();
                        count++;
                    }
                }
                for (int i = 0; i < train.numInstances(); i++) {
                    Instance inst = train.instance(i);
                    if (inst.isMissing(j)) {
                        sortedIndices[0][j][count] = i;
                        weights[0][j][count] = inst.weight();
                        count++;
                    }
                }
            } else {

                // Sorted indices are computed for numeric attributes
                for (int i = 0; i < train.numInstances(); i++) {
                    Instance inst = train.instance(i);
                    vals[i] = inst.value(j);
                }
                sortedIndices[0][j] = Utils.sort(vals);
                for (int i = 0; i < train.numInstances(); i++) {
                    weights[0][j][i] = train.instance(sortedIndices[0][j][i]).weight();
                }
            }
        }
    }

    // Compute initial class counts
    double[] classProbs = new double[train.numClasses()];
    double totalWeight = 0, totalSumSquared = 0;
    for (int i = 0; i < train.numInstances(); i++) {
        Instance inst = train.instance(i);
        if (data.classAttribute().isNominal()) {
            classProbs[(int) inst.classValue()] += inst.weight();
            totalWeight += inst.weight();
        } else {
            classProbs[0] += inst.classValue() * inst.weight();
            totalSumSquared += inst.classValue() * inst.classValue() * inst.weight();
            totalWeight += inst.weight();
        }
    }
    m_Tree = new Tree();
    double trainVariance = 0;
    if (data.classAttribute().isNumeric()) {
        trainVariance = m_Tree.singleVariance(classProbs[0], totalSumSquared, totalWeight) / totalWeight;
        classProbs[0] /= totalWeight;
    }

    // Build tree
    m_Tree.buildTree(sortedIndices, weights, train, totalWeight, classProbs, new Instances(train, 0), m_MinNum,
            m_MinVarianceProp * trainVariance, 0, m_MaxDepth, m_FeatureFrac, random);

    // Insert pruning data and perform reduced error pruning
    if (!m_NoPruning) {
        m_Tree.insertHoldOutSet(prune);
        m_Tree.reducedErrorPrune();
        m_Tree.backfitHoldOutSet();
    }
}

From source file:LabeledItemSet.java

License:Open Source License

/**
 * Splits the class attribute away. Depending on the invert flag, the instances without class attribute or only the class attribute of all instances is returned
 * @param instances the instances/*from w w  w  .  j ava2s .c om*/
 * @param invert flag; if true only the class attribute remains, otherweise the class attribute is the only attribute that is deleted.
 * @throws Exception exception if instances cannot be splitted
 * @return Instances without the class attribute or instances with only the class attribute
 */
public static Instances divide(Instances instances, boolean invert) throws Exception {

    Instances newInstances = new Instances(instances);
    if (instances.classIndex() < 0)
        throw new Exception("For class association rule mining a class attribute has to be specified.");
    if (invert) {
        for (int i = 0; i < newInstances.numAttributes(); i++) {
            if (i != newInstances.classIndex()) {
                newInstances.deleteAttributeAt(i);
                i--;
            }
        }
        return newInstances;
    } else {
        newInstances.setClassIndex(-1);
        newInstances.deleteAttributeAt(instances.classIndex());
        return newInstances;
    }
}

From source file:CJWeka.java

License:Open Source License

/**
 * This function sets what the m_numeric flag to represent the passed class
 * it also performs the normalization of the attributes if applicable
 * and sets up the info to normalize the class. (note that regardless of
 * the options it will fill an array with the range and base, set to
 * normalize all attributes and the class to be between -1 and 1)
 * @param inst the instances./*  ww  w  .j  av a  2 s  .  com*/
 * @return The modified instances. This needs to be done. If the attributes
 * are normalized then deep copies will be made of all the instances which
 * will need to be passed back out.
 */
private Instances setClassType(Instances inst) throws Exception {
    if (inst != null) {
        // x bounds
        double min = Double.POSITIVE_INFINITY;
        double max = Double.NEGATIVE_INFINITY;
        double value;
        m_attributeRanges = new double[inst.numAttributes()];
        m_attributeBases = new double[inst.numAttributes()];
        for (int noa = 0; noa < inst.numAttributes(); noa++) {
            min = Double.POSITIVE_INFINITY;
            max = Double.NEGATIVE_INFINITY;
            for (int i = 0; i < inst.numInstances(); i++) {
                if (!inst.instance(i).isMissing(noa)) {
                    value = inst.instance(i).value(noa);
                    if (value < min) {
                        min = value;
                    }
                    if (value > max) {
                        max = value;
                    }
                }
            }

            m_attributeRanges[noa] = (max - min) / 2;
            m_attributeBases[noa] = (max + min) / 2;
            if (noa != inst.classIndex() && m_normalizeAttributes) {
                for (int i = 0; i < inst.numInstances(); i++) {
                    if (m_attributeRanges[noa] != 0) {
                        inst.instance(i).setValue(noa,
                                (inst.instance(i).value(noa) - m_attributeBases[noa]) / m_attributeRanges[noa]);
                    } else {
                        inst.instance(i).setValue(noa, inst.instance(i).value(noa) - m_attributeBases[noa]);
                    }
                }
            }
        }
        if (inst.classAttribute().isNumeric()) {
            m_numeric = true;
        } else {
            m_numeric = false;
        }
    }
    return inst;
}