adaptedClusteringAlgorithms.MySimpleKMeans.java Source code

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Here is the source code for adaptedClusteringAlgorithms.MySimpleKMeans.java

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/*
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 *    SimpleKMeans.java
 *    Copyright (C) 2000 University of Waikato, Hamilton, New Zealand
 *
 */
package adaptedClusteringAlgorithms;

import java.util.Enumeration;
import java.util.HashMap;
import java.util.Random;
import java.util.Vector;

import adaptedSemanticMeasurers.CalculusInd;
import adaptedSemanticMeasurers.ChEBIInd;
import adaptedSemanticMeasurers.GOChEBIDir;
import adaptedSemanticMeasurers.GOChEBIInd;
import adaptedSemanticMeasurers.GOInd;
import adaptedSemanticMeasurers.GODir;
import adaptedSemanticMeasurers.CalculusDir;
import adaptedSemanticMeasurers.ChEBIDir;
import main.MyFirstClusterer;
import main.SESAME;
import weka.classifiers.rules.DecisionTableHashKey;
import weka.clusterers.NumberOfClustersRequestable;
import weka.clusterers.RandomizableClusterer;
import weka.core.Attribute;
import weka.core.Capabilities;
import weka.core.Capabilities.Capability;
import weka.core.DistanceFunction;
import weka.core.Instance;
import weka.core.Instances;
import weka.core.Option;
import weka.core.RevisionUtils;
import weka.core.Utils;
import weka.core.WeightedInstancesHandler;
import weka.filters.Filter;
import weka.filters.unsupervised.attribute.ReplaceMissingValues;

// --> WEKA's SimpleKMeans adapted to use SML's Semantic Measurers as if they were Euclidean

/**
 * <!-- globalinfo-start --> Cluster data using the k means algorithm
 * <p/>
 * <!-- globalinfo-end -->
 * 
 * <!-- options-start --> Valid options are:
 * <p/>
 * 
 * <pre>
 * -N &lt;num&gt;
 *  number of clusters.
 *  (default 2).
 * </pre>
 * 
 * <pre>
 * -V
 *  Display std. deviations for centroids.
 * </pre>
 * 
 * <pre>
 * -M
 *  Replace missing values with mean/mode.
 * </pre>
 * 
 * <pre>
 * -S &lt;num&gt;
 *  Random number seed.
 *  (default 10)
 * </pre>
 * 
 * <pre>
 * -A &lt;classname and options&gt;
 *  Distance function to be used for instance comparison
 *  (default adaptedSemanticMeasurers.ChEBIDir)
 * </pre>
 * 
 * <pre>
 * -I &lt;num&gt;
 *  Maximum number of iterations.
 * </pre>
 * 
 * <pre>
 * -O 
 *  Preserve order of instances.
 * </pre>
 * 
 * 
 * <!-- options-end -->
 * 
 * @author Mark Hall (mhall@cs.waikato.ac.nz)
 * @author Eibe Frank (eibe@cs.waikato.ac.nz)
 * @version $Revision: 10537 $
 * @see RandomizableClusterer
 */
public class MySimpleKMeans extends RandomizableClusterer
        implements NumberOfClustersRequestable, WeightedInstancesHandler {

    /** for serialization */
    static final long serialVersionUID = -3235809600124455376L;

    /**
     * replace missing values in training instances
     */
    private ReplaceMissingValues m_ReplaceMissingFilter;

    /**
     * number of clusters to generate
     */
    private int m_NumClusters = 2;

    /**
     * holds the cluster centroids
     */
    private Instances m_ClusterCentroids;

    /**
     * Holds the standard deviations of the numeric attributes in each cluster
     */
    private Instances m_ClusterStdDevs;

    /**
     * For each cluster, holds the frequency counts for the values of each nominal
     * attribute
     */
    private int[][][] m_ClusterNominalCounts;
    private int[][] m_ClusterMissingCounts;

    /**
     * Stats on the full data set for comparison purposes In case the attribute is
     * numeric the value is the mean and if the attribute is nominal then it's
     * mode is saved
     */
    private double[] m_FullMeansOrMediansOrModes;
    private double[] m_FullStdDevs;
    private int[][] m_FullNominalCounts;
    private int[] m_FullMissingCounts;

    /**
     * Display standard deviations for numeric atts
     */
    private boolean m_displayStdDevs;

    /**
     * Replace missing values globally?
     */
    private boolean m_dontReplaceMissing = false;

    /**
     * The number of instances in each cluster
     */
    private int[] m_ClusterSizes;

    /**
     * Maximum number of iterations to be executed
     */
    private int m_MaxIterations = 500;

    /**
     * Keep track of the number of iterations completed before convergence
     */
    private int m_Iterations = 0;

    /**
     * Holds the squared errors for all clusters
     */
    private double[] m_squaredErrors;

    /** the distance function used. */
    protected DistanceFunction m_DistanceFunction = new ChEBIDir();

    /**
     * Preserve order of instances
     */
    private boolean m_PreserveOrder = false;

    /**
     * Assignments obtained
     */
    protected int[] m_Assignments = null;

    /**
     * the default constructor
     */
    public MySimpleKMeans() {
        super();

        m_SeedDefault = 10;
        setSeed(m_SeedDefault);
    }

    /**
     * Returns a string describing this clusterer
     * 
     * @return a description of the evaluator suitable for displaying in the
     *         explorer/experimenter gui
     */
    public String globalInfo() {
        return "Cluster data using the k means algorithm. By default use " + "the ChEBIDir distance."
                + " The centroids are computed as the component-wise mean.";
    }

    /**
     * Returns default capabilities of the clusterer.
     * 
     * @return the capabilities of this clusterer
     */
    @Override
    public Capabilities getCapabilities() {
        Capabilities result = super.getCapabilities();
        result.disableAll();
        result.enable(Capability.NO_CLASS);

        // attributes
        result.enable(Capability.NOMINAL_ATTRIBUTES);
        result.enable(Capability.NUMERIC_ATTRIBUTES);
        result.enable(Capability.MISSING_VALUES);

        return result;
    }

    /**
     * Generates a clusterer. Has to initialize all fields of the clusterer that
     * are not being set via options.
     * 
     * @param data set of instances serving as training data
     * @throws Exception if the clusterer has not been generated successfully
     */
    @Override
    public void buildClusterer(Instances data) throws Exception {

        if (!SESAME.SESAME_GUI)
            MyFirstClusterer.weka_gui = true;

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

        m_Iterations = 0;

        m_ReplaceMissingFilter = new ReplaceMissingValues();
        Instances instances = new Instances(data);

        instances.setClassIndex(-1);
        if (!m_dontReplaceMissing) {
            m_ReplaceMissingFilter.setInputFormat(instances);
            instances = Filter.useFilter(instances, m_ReplaceMissingFilter);
        }

        m_FullMissingCounts = new int[instances.numAttributes()];
        if (m_displayStdDevs) {
            m_FullStdDevs = new double[instances.numAttributes()];
        }
        m_FullNominalCounts = new int[instances.numAttributes()][0];

        m_FullMeansOrMediansOrModes = moveCentroid(0, instances, false);
        for (int i = 0; i < instances.numAttributes(); i++) {
            m_FullMissingCounts[i] = instances.attributeStats(i).missingCount;
            if (instances.attribute(i).isNumeric()) {
                if (m_displayStdDevs) {
                    m_FullStdDevs[i] = Math.sqrt(instances.variance(i));
                }
                if (m_FullMissingCounts[i] == instances.numInstances()) {
                    m_FullMeansOrMediansOrModes[i] = Double.NaN; // mark missing as mean
                }
            } else {
                m_FullNominalCounts[i] = instances.attributeStats(i).nominalCounts;
                if (m_FullMissingCounts[i] > m_FullNominalCounts[i][Utils.maxIndex(m_FullNominalCounts[i])]) {
                    m_FullMeansOrMediansOrModes[i] = -1; // mark missing as most common
                                                         // value
                }
            }
        }

        m_ClusterCentroids = new Instances(instances, m_NumClusters);
        int[] clusterAssignments = new int[instances.numInstances()];

        if (m_PreserveOrder) {
            m_Assignments = clusterAssignments;
        }

        m_DistanceFunction.setInstances(instances);

        Random RandomO = new Random(getSeed());
        int instIndex;
        HashMap initC = new HashMap();
        DecisionTableHashKey hk = null;

        Instances initInstances = null;
        if (m_PreserveOrder) {
            initInstances = new Instances(instances);
        } else {
            initInstances = instances;
        }

        for (int j = initInstances.numInstances() - 1; j >= 0; j--) {
            instIndex = RandomO.nextInt(j + 1);
            hk = new DecisionTableHashKey(initInstances.instance(instIndex), initInstances.numAttributes(), true);
            if (!initC.containsKey(hk)) {
                m_ClusterCentroids.add(initInstances.instance(instIndex));
                initC.put(hk, null);
            }
            initInstances.swap(j, instIndex);

            if (m_ClusterCentroids.numInstances() == m_NumClusters) {
                break;
            }
        }

        m_NumClusters = m_ClusterCentroids.numInstances();

        // removing reference
        initInstances = null;

        int i;
        boolean converged = false;
        int emptyClusterCount;
        Instances[] tempI = new Instances[m_NumClusters];
        m_squaredErrors = new double[m_NumClusters];
        m_ClusterNominalCounts = new int[m_NumClusters][instances.numAttributes()][0];
        m_ClusterMissingCounts = new int[m_NumClusters][instances.numAttributes()];
        while (!converged) {
            emptyClusterCount = 0;
            m_Iterations++;
            converged = true;
            for (i = 0; i < instances.numInstances(); i++) {
                Instance toCluster = instances.instance(i);
                int newC = clusterProcessedInstance(toCluster, true);
                if (newC != clusterAssignments[i]) {
                    converged = false;
                }
                clusterAssignments[i] = newC;
            }

            // update centroids
            m_ClusterCentroids = new Instances(instances, m_NumClusters);
            for (i = 0; i < m_NumClusters; i++) {
                tempI[i] = new Instances(instances, 0);
            }
            for (i = 0; i < instances.numInstances(); i++) {
                tempI[clusterAssignments[i]].add(instances.instance(i));
            }
            for (i = 0; i < m_NumClusters; i++) {
                if (tempI[i].numInstances() == 0) {
                    // empty cluster
                    emptyClusterCount++;
                } else {
                    moveCentroid(i, tempI[i], true);
                }
            }

            if (m_Iterations == m_MaxIterations) {
                converged = true;
            }

            if (emptyClusterCount > 0) {
                m_NumClusters -= emptyClusterCount;
                if (converged) {
                    Instances[] t = new Instances[m_NumClusters];
                    int index = 0;
                    for (int k = 0; k < tempI.length; k++) {
                        if (tempI[k].numInstances() > 0) {
                            t[index] = tempI[k];

                            for (i = 0; i < tempI[k].numAttributes(); i++) {
                                m_ClusterNominalCounts[index][i] = m_ClusterNominalCounts[k][i];
                            }
                            index++;
                        }
                    }
                    tempI = t;
                } else {
                    tempI = new Instances[m_NumClusters];
                }
            }

            if (!converged) {
                m_squaredErrors = new double[m_NumClusters];
                m_ClusterNominalCounts = new int[m_NumClusters][instances.numAttributes()][0];
            }
        }

        if (m_displayStdDevs) {
            m_ClusterStdDevs = new Instances(instances, m_NumClusters);
        }
        m_ClusterSizes = new int[m_NumClusters];
        for (i = 0; i < m_NumClusters; i++) {
            if (m_displayStdDevs) {
                double[] vals2 = new double[instances.numAttributes()];
                for (int j = 0; j < instances.numAttributes(); j++) {
                    if (instances.attribute(j).isNumeric()) {
                        vals2[j] = Math.sqrt(tempI[i].variance(j));
                    } else {
                        vals2[j] = Instance.missingValue();
                    }
                }
                m_ClusterStdDevs.add(new Instance(1.0, vals2));
            }
            m_ClusterSizes[i] = tempI[i].numInstances();
        }

        // Save memory!!
        m_DistanceFunction.clean();

        if (!SESAME.SESAME_GUI)
            MyFirstClusterer.weka_gui = true;
    }

    /**
     * Move the centroid to it's new coordinates. Generate the centroid
     * coordinates based on it's members (objects assigned to the cluster of the
     * centroid) and the distance function being used.
     * 
     * @param centroidIndex index of the centroid which the coordinates will be
     *          computed
     * @param members the objects that are assigned to the cluster of this
     *          centroid
     * @param updateClusterInfo if the method is supposed to update the m_Cluster
     *          arrays
     * @return the centroid coordinates
     */
    protected double[] moveCentroid(int centroidIndex, Instances members, boolean updateClusterInfo) {
        double[] vals = new double[members.numAttributes()];

        for (int j = 0; j < members.numAttributes(); j++) {

            // The centroid is the mean point. If the attribute is nominal, the centroid is the mode
            if (m_DistanceFunction instanceof ChEBIInd || m_DistanceFunction instanceof ChEBIDir
                    || m_DistanceFunction instanceof GOInd || m_DistanceFunction instanceof GODir
                    || m_DistanceFunction instanceof GOChEBIInd || m_DistanceFunction instanceof GOChEBIDir
                    || m_DistanceFunction instanceof CalculusInd || m_DistanceFunction instanceof CalculusDir
                    || members.attribute(j).isNominal()) {
                vals[j] = members.meanOrMode(j);
            }

            if (updateClusterInfo) {
                m_ClusterMissingCounts[centroidIndex][j] = members.attributeStats(j).missingCount;
                m_ClusterNominalCounts[centroidIndex][j] = members.attributeStats(j).nominalCounts;
                if (members.attribute(j).isNominal()) {
                    if (m_ClusterMissingCounts[centroidIndex][j] > m_ClusterNominalCounts[centroidIndex][j][Utils
                            .maxIndex(m_ClusterNominalCounts[centroidIndex][j])]) {
                        vals[j] = Instance.missingValue(); // mark mode as missing
                    }
                } else {
                    if (m_ClusterMissingCounts[centroidIndex][j] == members.numInstances()) {
                        vals[j] = Instance.missingValue(); // mark mean as missing
                    }
                }
            }
        }
        if (updateClusterInfo) {
            m_ClusterCentroids.add(new Instance(1.0, vals));
        }
        return vals;
    }

    /**
     * clusters an instance that has been through the filters
     * 
     * @param instance the instance to assign a cluster to
     * @param updateErrors if true, update the within clusters sum of errors
     * @return a cluster number
     */
    private int clusterProcessedInstance(Instance instance, boolean updateErrors) {
        double minDist = Integer.MAX_VALUE;
        int bestCluster = 0;
        for (int i = 0; i < m_NumClusters; i++) {
            double dist = m_DistanceFunction.distance(instance, m_ClusterCentroids.instance(i));
            if (dist < minDist) {
                minDist = dist;
                bestCluster = i;
            }
        }
        if (updateErrors) {
            if (m_DistanceFunction instanceof ChEBIInd || m_DistanceFunction instanceof ChEBIDir
                    || m_DistanceFunction instanceof GOInd || m_DistanceFunction instanceof GODir
                    || m_DistanceFunction instanceof GOChEBIInd || m_DistanceFunction instanceof GOChEBIDir
                    || m_DistanceFunction instanceof CalculusInd || m_DistanceFunction instanceof CalculusDir) {
                minDist *= minDist;
            }
            m_squaredErrors[bestCluster] += minDist;
        }
        return bestCluster;
    }

    /**
     * Classifies a given instance.
     * 
     * @param instance the instance to be assigned to a cluster
     * @return the number of the assigned cluster as an interger if the class is
     *         enumerated, otherwise the predicted value
     * @throws Exception if instance could not be classified successfully
     */
    @Override
    public int clusterInstance(Instance instance) throws Exception {
        Instance inst = null;
        if (!m_dontReplaceMissing) {
            m_ReplaceMissingFilter.input(instance);
            m_ReplaceMissingFilter.batchFinished();
            inst = m_ReplaceMissingFilter.output();
        } else {
            inst = instance;
        }

        return clusterProcessedInstance(inst, false);
    }

    /**
     * Returns the number of clusters.
     * 
     * @return the number of clusters generated for a training dataset.
     * @throws Exception if number of clusters could not be returned successfully
     */
    @Override
    public int numberOfClusters() throws Exception {
        return m_NumClusters;
    }

    /**
     * Returns an enumeration describing the available options.
     * 
     * @return an enumeration of all the available options.
     */
    @Override
    public Enumeration listOptions() {
        Vector result = new Vector();

        result.addElement(new Option("\tnumber of clusters.\n" + "\t(default 2).", "N", 1, "-N <num>"));
        result.addElement(new Option("\tDisplay std. deviations for centroids.\n", "V", 0, "-V"));
        result.addElement(new Option("\tDon't replace missing values with mean/mode.\n", "M", 0, "-M"));

        result.add(new Option("\tDistance function to use.\n" + "\t(default: adaptedSemanticMeasurers.ChEBIDir)",
                "A", 1, "-A <classname and options>"));

        result.add(new Option("\tMaximum number of iterations.\n", "I", 1, "-I <num>"));

        result.addElement(new Option("\tPreserve order of instances.\n", "O", 0, "-O"));

        Enumeration en = super.listOptions();
        while (en.hasMoreElements()) {
            result.addElement(en.nextElement());
        }

        return result.elements();
    }

    /**
     * Returns the tip text for this property
     * 
     * @return tip text for this property suitable for displaying in the
     *         explorer/experimenter gui
     */
    public String numClustersTipText() {
        return "set number of clusters";
    }

    /**
     * set the number of clusters to generate
     * 
     * @param n the number of clusters to generate
     * @throws Exception if number of clusters is negative
     */
    @Override
    public void setNumClusters(int n) throws Exception {
        if (n <= 0) {
            throw new Exception("Number of clusters must be > 0");
        }
        m_NumClusters = n;
    }

    /**
     * gets the number of clusters to generate
     * 
     * @return the number of clusters to generate
     */
    public int getNumClusters() {
        return m_NumClusters;
    }

    /**
     * Returns the tip text for this property
     * 
     * @return tip text for this property suitable for displaying in the
     *         explorer/experimenter gui
     */
    public String maxIterationsTipText() {
        return "set maximum number of iterations";
    }

    /**
     * set the maximum number of iterations to be executed
     * 
     * @param n the maximum number of iterations
     * @throws Exception if maximum number of iteration is smaller than 1
     */
    public void setMaxIterations(int n) throws Exception {
        if (n <= 0) {
            throw new Exception("Maximum number of iterations must be > 0");
        }
        m_MaxIterations = n;
    }

    /**
     * gets the number of maximum iterations to be executed
     * 
     * @return the number of clusters to generate
     */
    public int getMaxIterations() {
        return m_MaxIterations;
    }

    /**
     * Returns the tip text for this property
     * 
     * @return tip text for this property suitable for displaying in the
     *         explorer/experimenter gui
     */
    public String displayStdDevsTipText() {
        return "Display std deviations of numeric attributes " + "and counts of nominal attributes.";
    }

    /**
     * Sets whether standard deviations and nominal count Should be displayed in
     * the clustering output
     * 
     * @param stdD true if std. devs and counts should be displayed
     */
    public void setDisplayStdDevs(boolean stdD) {
        m_displayStdDevs = stdD;
    }

    /**
     * Gets whether standard deviations and nominal count Should be displayed in
     * the clustering output
     * 
     * @return true if std. devs and counts should be displayed
     */
    public boolean getDisplayStdDevs() {
        return m_displayStdDevs;
    }

    /**
     * Returns the tip text for this property
     * 
     * @return tip text for this property suitable for displaying in the
     *         explorer/experimenter gui
     */
    public String dontReplaceMissingValuesTipText() {
        return "Replace missing values globally with mean/mode.";
    }

    /**
     * Sets whether missing values are to be replaced
     * 
     * @param r true if missing values are to be replaced
     */
    public void setDontReplaceMissingValues(boolean r) {
        m_dontReplaceMissing = r;
    }

    /**
     * Gets whether missing values are to be replaced
     * 
     * @return true if missing values are to be replaced
     */
    public boolean getDontReplaceMissingValues() {
        return m_dontReplaceMissing;
    }

    /**
     * Returns the tip text for this property.
     * 
     * @return tip text for this property suitable for displaying in the
     *         explorer/experimenter gui
     */
    public String distanceFunctionTipText() {
        return "The distance function to use for instances comparison "
                + "(default: adaptedSemanticMeasurers.ChEBIDir). ";
    }

    /**
     * returns the distance function currently in use.
     * 
     * @return the distance function
     */
    public DistanceFunction getDistanceFunction() {
        return m_DistanceFunction;
    }

    /**
     * sets the distance function to use for instance comparison.
     * 
     * @param df the new distance function to use
     * @throws Exception if instances cannot be processed
     */
    public void setDistanceFunction(DistanceFunction df) throws Exception {
        if (!(df instanceof ChEBIInd) && !(df instanceof ChEBIDir) && !(df instanceof GOInd)
                && !(df instanceof GODir) && !(df instanceof GOChEBIInd) && !(df instanceof GOChEBIDir)
                && !(df instanceof CalculusInd) && !(df instanceof CalculusDir)) {
            throw new Exception("MySimpleKMeans does not currently support that distance.");
        }
        m_DistanceFunction = df;
    }

    /**
     * Returns the tip text for this property
     * 
     * @return tip text for this property suitable for displaying in the
     *         explorer/experimenter gui
     */
    public String preserveInstancesOrderTipText() {
        return "Preserve order of instances.";
    }

    /**
     * Sets whether order of instances must be preserved
     * 
     * @param r true if missing values are to be replaced
     */
    public void setPreserveInstancesOrder(boolean r) {
        m_PreserveOrder = r;
    }

    /**
     * Gets whether order of instances must be preserved
     * 
     * @return true if missing values are to be replaced
     */
    public boolean getPreserveInstancesOrder() {
        return m_PreserveOrder;
    }

    /**
     * Parses a given list of options.
     * <p/>
     * 
     * <!-- options-start --> Valid options are:
     * <p/>
     * 
     * <pre>
     * -N &lt;num&gt;
     *  number of clusters.
     *  (default 2).
     * </pre>
     * 
     * <pre>
     * -V
     *  Display std. deviations for centroids.
     * </pre>
     * 
     * <pre>
     * -M
     *  Replace missing values with mean/mode.
     * </pre>
     * 
     * <pre>
     * -S &lt;num&gt;
     *  Random number seed.
     *  (default 10)
     * </pre>
     * 
     * <pre>
     * -A &lt;classname and options&gt;
     *  Distance function to be used for instance comparison
     *  (adaptedSemanticMeasurers.ChEBIDir)
     * </pre>
     * 
     * <pre>
     * -I &lt;num&gt;
     *  Maximum number of iterations.
     * </pre>
     * 
     * <pre>
     * -O
     *  Preserve order of instances.
     * </pre>
     * 
     * <!-- options-end -->
     * 
     * @param options the list of options as an array of strings
     * @throws Exception if an option is not supported
     */
    @Override
    public void setOptions(String[] options) throws Exception {

        m_displayStdDevs = Utils.getFlag("V", options);
        m_dontReplaceMissing = Utils.getFlag("M", options);

        String optionString = Utils.getOption('N', options);

        if (optionString.length() != 0) {
            setNumClusters(Integer.parseInt(optionString));
        }

        optionString = Utils.getOption("I", options);
        if (optionString.length() != 0) {
            setMaxIterations(Integer.parseInt(optionString));
        }

        String distFunctionClass = Utils.getOption('A', options);
        if (distFunctionClass.length() != 0) {
            String distFunctionClassSpec[] = Utils.splitOptions(distFunctionClass);
            if (distFunctionClassSpec.length == 0) {
                throw new Exception("Invalid DistanceFunction specification string.");
            }
            String className = distFunctionClassSpec[0];
            distFunctionClassSpec[0] = "";

            setDistanceFunction(
                    (DistanceFunction) Utils.forName(DistanceFunction.class, className, distFunctionClassSpec));
        } else {
            setDistanceFunction(new ChEBIDir());
        }

        m_PreserveOrder = Utils.getFlag("O", options);

        super.setOptions(options);
    }

    /**
     * Gets the current settings of SimpleKMeans
     * 
     * @return an array of strings suitable for passing to setOptions()
     */
    @Override
    public String[] getOptions() {
        int i;
        Vector result;
        String[] options;

        result = new Vector();

        if (m_displayStdDevs) {
            result.add("-V");
        }

        if (m_dontReplaceMissing) {
            result.add("-M");
        }

        result.add("-N");
        result.add("" + getNumClusters());

        result.add("-A");
        result.add(
                (m_DistanceFunction.getClass().getName() + " " + Utils.joinOptions(m_DistanceFunction.getOptions()))
                        .trim());

        result.add("-I");
        result.add("" + getMaxIterations());

        if (m_PreserveOrder) {
            result.add("-O");
        }

        options = super.getOptions();
        for (i = 0; i < options.length; i++) {
            result.add(options[i]);
        }

        return (String[]) result.toArray(new String[result.size()]);
    }

    /**
     * return a string describing this clusterer
     * 
     * @return a description of the clusterer as a string
     */
    @Override
    public String toString() {
        if (m_ClusterCentroids == null) {
            return "No clusterer built yet!";
        }

        int maxWidth = 0;
        int maxAttWidth = 0;
        boolean containsNumeric = false;
        for (int i = 0; i < m_NumClusters; i++) {
            for (int j = 0; j < m_ClusterCentroids.numAttributes(); j++) {
                if (m_ClusterCentroids.attribute(j).name().length() > maxAttWidth) {
                    maxAttWidth = m_ClusterCentroids.attribute(j).name().length();
                }
                if (m_ClusterCentroids.attribute(j).isNumeric()) {
                    containsNumeric = true;
                    double width = Math.log(Math.abs(m_ClusterCentroids.instance(i).value(j))) / Math.log(10.0);
                    // System.err.println(m_ClusterCentroids.instance(i).value(j)+" "+width);
                    if (width < 0) {
                        width = 1;
                    }
                    // decimal + # decimal places + 1
                    width += 6.0;
                    if ((int) width > maxWidth) {
                        maxWidth = (int) width;
                    }
                }
            }
        }

        for (int i = 0; i < m_ClusterCentroids.numAttributes(); i++) {
            if (m_ClusterCentroids.attribute(i).isNominal()) {
                Attribute a = m_ClusterCentroids.attribute(i);
                for (int j = 0; j < m_ClusterCentroids.numInstances(); j++) {
                    String val = a.value((int) m_ClusterCentroids.instance(j).value(i));
                    if (val.length() > maxWidth) {
                        maxWidth = val.length();
                    }
                }
                for (int j = 0; j < a.numValues(); j++) {
                    String val = a.value(j) + " ";
                    if (val.length() > maxAttWidth) {
                        maxAttWidth = val.length();
                    }
                }
            }
        }

        if (m_displayStdDevs) {
            // check for maximum width of maximum frequency count
            for (int i = 0; i < m_ClusterCentroids.numAttributes(); i++) {
                if (m_ClusterCentroids.attribute(i).isNominal()) {
                    int maxV = Utils.maxIndex(m_FullNominalCounts[i]);
                    /*
                     * int percent = (int)((double)m_FullNominalCounts[i][maxV] /
                     * Utils.sum(m_ClusterSizes) * 100.0);
                     */
                    int percent = 6; // max percent width (100%)
                    String nomV = "" + m_FullNominalCounts[i][maxV];
                    // + " (" + percent + "%)";
                    if (nomV.length() + percent > maxWidth) {
                        maxWidth = nomV.length() + 1;
                    }
                }
            }
        }

        // check for size of cluster sizes
        for (int m_ClusterSize : m_ClusterSizes) {
            String size = "(" + m_ClusterSize + ")";
            if (size.length() > maxWidth) {
                maxWidth = size.length();
            }
        }

        if (m_displayStdDevs && maxAttWidth < "missing".length()) {
            maxAttWidth = "missing".length();
        }

        String plusMinus = "+/-";
        maxAttWidth += 2;
        if (m_displayStdDevs && containsNumeric) {
            maxWidth += plusMinus.length();
        }
        if (maxAttWidth < "Attribute".length() + 2) {
            maxAttWidth = "Attribute".length() + 2;
        }

        if (maxWidth < "Full Data".length()) {
            maxWidth = "Full Data".length() + 1;
        }

        if (maxWidth < "missing".length()) {
            maxWidth = "missing".length() + 1;
        }

        StringBuffer temp = new StringBuffer();
        // String naString = "N/A";

        /*
         * for (int i = 0; i < maxWidth+2; i++) { naString += " "; }
         */
        temp.append("\nkMeans\n======\n");
        temp.append("\nNumber of iterations: " + m_Iterations + "\n");

        if (m_DistanceFunction instanceof ChEBIInd || m_DistanceFunction instanceof ChEBIDir
                || m_DistanceFunction instanceof GOInd || m_DistanceFunction instanceof GODir
                || m_DistanceFunction instanceof GOChEBIInd || m_DistanceFunction instanceof GOChEBIDir
                || m_DistanceFunction instanceof CalculusInd || m_DistanceFunction instanceof CalculusDir) {
            temp.append("Within cluster sum of squared errors: " + Utils.sum(m_squaredErrors));
        } else {
            temp.append("Sum of within cluster distances: " + Utils.sum(m_squaredErrors));
        }

        if (!m_dontReplaceMissing) {
            temp.append("\nMissing values globally replaced with mean/mode");
        }

        temp.append("\n\nCluster centroids:\n");
        temp.append(pad("Cluster#", " ", (maxAttWidth + (maxWidth * 2 + 2)) - "Cluster#".length(), true));

        temp.append("\n");
        temp.append(pad("Attribute", " ", maxAttWidth - "Attribute".length(), false));

        temp.append(pad("Full Data", " ", maxWidth + 1 - "Full Data".length(), true));

        // cluster numbers
        for (int i = 0; i < m_NumClusters; i++) {
            String clustNum = "" + i;
            temp.append(pad(clustNum, " ", maxWidth + 1 - clustNum.length(), true));
        }
        temp.append("\n");

        // cluster sizes
        String cSize = "(" + Utils.sum(m_ClusterSizes) + ")";
        temp.append(pad(cSize, " ", maxAttWidth + maxWidth + 1 - cSize.length(), true));
        for (int i = 0; i < m_NumClusters; i++) {
            cSize = "(" + m_ClusterSizes[i] + ")";
            temp.append(pad(cSize, " ", maxWidth + 1 - cSize.length(), true));
        }
        temp.append("\n");

        temp.append(pad("", "=", maxAttWidth
                + (maxWidth * (m_ClusterCentroids.numInstances() + 1) + m_ClusterCentroids.numInstances() + 1),
                true));
        temp.append("\n");

        for (int i = 0; i < m_ClusterCentroids.numAttributes(); i++) {
            String attName = m_ClusterCentroids.attribute(i).name();
            temp.append(attName);
            for (int j = 0; j < maxAttWidth - attName.length(); j++) {
                temp.append(" ");
            }

            String strVal;
            String valMeanMode;
            // full data
            if (m_ClusterCentroids.attribute(i).isNominal()) {
                if (m_FullMeansOrMediansOrModes[i] == -1) { // missing
                    valMeanMode = pad("missing", " ", maxWidth + 1 - "missing".length(), true);
                } else {
                    valMeanMode = pad(
                            (strVal = m_ClusterCentroids.attribute(i).value((int) m_FullMeansOrMediansOrModes[i])),
                            " ", maxWidth + 1 - strVal.length(), true);
                }
            } else {
                if (Double.isNaN(m_FullMeansOrMediansOrModes[i])) {
                    valMeanMode = pad("missing", " ", maxWidth + 1 - "missing".length(), true);
                } else {
                    valMeanMode = pad(
                            (strVal = Utils.doubleToString(m_FullMeansOrMediansOrModes[i], maxWidth, 4).trim()),
                            " ", maxWidth + 1 - strVal.length(), true);
                }
            }
            temp.append(valMeanMode);

            for (int j = 0; j < m_NumClusters; j++) {
                if (m_ClusterCentroids.attribute(i).isNominal()) {
                    if (m_ClusterCentroids.instance(j).isMissing(i)) {
                        valMeanMode = pad("missing", " ", maxWidth + 1 - "missing".length(), true);
                    } else {
                        valMeanMode = pad(
                                (strVal = m_ClusterCentroids.attribute(i)
                                        .value((int) m_ClusterCentroids.instance(j).value(i))),
                                " ", maxWidth + 1 - strVal.length(), true);
                    }
                } else {
                    if (m_ClusterCentroids.instance(j).isMissing(i)) {
                        valMeanMode = pad("missing", " ", maxWidth + 1 - "missing".length(), true);
                    } else {
                        valMeanMode = pad((strVal = Utils
                                .doubleToString(m_ClusterCentroids.instance(j).value(i), maxWidth, 4).trim()), " ",
                                maxWidth + 1 - strVal.length(), true);
                    }
                }
                temp.append(valMeanMode);
            }
            temp.append("\n");

            if (m_displayStdDevs) {
                // Std devs/max nominal
                String stdDevVal = "";

                if (m_ClusterCentroids.attribute(i).isNominal()) {
                    // Do the values of the nominal attribute
                    Attribute a = m_ClusterCentroids.attribute(i);
                    for (int j = 0; j < a.numValues(); j++) {
                        // full data
                        String val = "  " + a.value(j);
                        temp.append(pad(val, " ", maxAttWidth + 1 - val.length(), false));
                        int count = m_FullNominalCounts[i][j];
                        int percent = (int) ((double) m_FullNominalCounts[i][j] / Utils.sum(m_ClusterSizes)
                                * 100.0);
                        String percentS = "" + percent + "%)";
                        percentS = pad(percentS, " ", 5 - percentS.length(), true);
                        stdDevVal = "" + count + " (" + percentS;
                        stdDevVal = pad(stdDevVal, " ", maxWidth + 1 - stdDevVal.length(), true);
                        temp.append(stdDevVal);

                        // Clusters
                        for (int k = 0; k < m_NumClusters; k++) {
                            count = m_ClusterNominalCounts[k][i][j];
                            percent = (int) ((double) m_ClusterNominalCounts[k][i][j] / m_ClusterSizes[k] * 100.0);
                            percentS = "" + percent + "%)";
                            percentS = pad(percentS, " ", 5 - percentS.length(), true);
                            stdDevVal = "" + count + " (" + percentS;
                            stdDevVal = pad(stdDevVal, " ", maxWidth + 1 - stdDevVal.length(), true);
                            temp.append(stdDevVal);
                        }
                        temp.append("\n");
                    }
                    // missing (if any)
                    if (m_FullMissingCounts[i] > 0) {
                        // Full data
                        temp.append(pad("  missing", " ", maxAttWidth + 1 - "  missing".length(), false));
                        int count = m_FullMissingCounts[i];
                        int percent = (int) ((double) m_FullMissingCounts[i] / Utils.sum(m_ClusterSizes) * 100.0);
                        String percentS = "" + percent + "%)";
                        percentS = pad(percentS, " ", 5 - percentS.length(), true);
                        stdDevVal = "" + count + " (" + percentS;
                        stdDevVal = pad(stdDevVal, " ", maxWidth + 1 - stdDevVal.length(), true);
                        temp.append(stdDevVal);

                        // Clusters
                        for (int k = 0; k < m_NumClusters; k++) {
                            count = m_ClusterMissingCounts[k][i];
                            percent = (int) ((double) m_ClusterMissingCounts[k][i] / m_ClusterSizes[k] * 100.0);
                            percentS = "" + percent + "%)";
                            percentS = pad(percentS, " ", 5 - percentS.length(), true);
                            stdDevVal = "" + count + " (" + percentS;
                            stdDevVal = pad(stdDevVal, " ", maxWidth + 1 - stdDevVal.length(), true);
                            temp.append(stdDevVal);
                        }

                        temp.append("\n");
                    }

                    temp.append("\n");
                } else {
                    // Full data
                    if (Double.isNaN(m_FullMeansOrMediansOrModes[i])) {
                        stdDevVal = pad("--", " ", maxAttWidth + maxWidth + 1 - 2, true);
                    } else {
                        stdDevVal = pad(
                                (strVal = plusMinus + Utils.doubleToString(m_FullStdDevs[i], maxWidth, 4).trim()),
                                " ", maxWidth + maxAttWidth + 1 - strVal.length(), true);
                    }
                    temp.append(stdDevVal);

                    // Clusters
                    for (int j = 0; j < m_NumClusters; j++) {
                        if (m_ClusterCentroids.instance(j).isMissing(i)) {
                            stdDevVal = pad("--", " ", maxWidth + 1 - 2, true);
                        } else {
                            stdDevVal = pad((strVal = plusMinus + Utils
                                    .doubleToString(m_ClusterStdDevs.instance(j).value(i), maxWidth, 4).trim()),
                                    " ", maxWidth + 1 - strVal.length(), true);
                        }
                        temp.append(stdDevVal);
                    }
                    temp.append("\n\n");
                }
            }
        }

        temp.append("\n\n");
        return temp.toString();
    }

    private String pad(String source, String padChar, int length, boolean leftPad) {
        StringBuffer temp = new StringBuffer();

        if (leftPad) {
            for (int i = 0; i < length; i++) {
                temp.append(padChar);
            }
            temp.append(source);
        } else {
            temp.append(source);
            for (int i = 0; i < length; i++) {
                temp.append(padChar);
            }
        }
        return temp.toString();
    }

    /**
     * Gets the the cluster centroids
     * 
     * @return the cluster centroids
     */
    public Instances getClusterCentroids() {
        return m_ClusterCentroids;
    }

    /**
     * Gets the standard deviations of the numeric attributes in each cluster
     * 
     * @return the standard deviations of the numeric attributes in each cluster
     */
    public Instances getClusterStandardDevs() {
        return m_ClusterStdDevs;
    }

    /**
     * Returns for each cluster the frequency counts for the values of each
     * nominal attribute
     * 
     * @return the counts
     */
    public int[][][] getClusterNominalCounts() {
        return m_ClusterNominalCounts;
    }

    /**
     * Gets the squared error for all clusters
     * 
     * @return the squared error
     */
    public double getSquaredError() {
        return Utils.sum(m_squaredErrors);
    }

    /**
     * Gets the number of instances in each cluster
     * 
     * @return The number of instances in each cluster
     */
    public int[] getClusterSizes() {
        return m_ClusterSizes;
    }

    /**
     * Gets the number of iterations completed before convergence
     * 
     * @return The number of iterations completed before convergence
     */
    public int getNumIterations() {
        return m_Iterations;
    }

    /**
     * Gets the assignments for each instance
     * 
     * @return Array of indexes of the centroid assigned to each instance
     * @throws Exception if order of instances wasn't preserved or no assignments
     *           were made
     */
    public int[] getAssignments() throws Exception {
        if (!m_PreserveOrder) {
            throw new Exception("The assignments are only available when order of instances is preserved (-O)");
        }
        if (m_Assignments == null) {
            throw new Exception("No assignments made.");
        }
        return m_Assignments;
    }

    /**
     * Returns the revision string.
     * 
     * @return the revision
     */
    @Override
    public String getRevision() {
        return RevisionUtils.extract("$Revision: 10537 $");
    }

    /**
     * Main method for testing this class.
     * 
     * @param argv should contain the following arguments:
     *          <p>
     *          -t training file [-N number of clusters]
     */
    public static void main(String[] argv) {
        runClusterer(new MySimpleKMeans(), argv);
    }
}