/*
 *    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.
 */

/*
 *    Copyright (C) 2004
 *    & Matthias Schubert (schubert@dbs.ifi.lmu.de)
 *    & Zhanna Melnikova-Albrecht (melnikov@cip.ifi.lmu.de)
 *    & Rainer Holzmann (holzmann@cip.ifi.lmu.de) 
 */

package weka.clusterers;

import weka.clusterers.forOPTICSAndDBScan.DataObjects.DataObject;
import weka.clusterers.forOPTICSAndDBScan.Databases.Database;
import weka.clusterers.forOPTICSAndDBScan.OPTICS_GUI.OPTICS_Visualizer;
import weka.clusterers.forOPTICSAndDBScan.OPTICS_GUI.SERObject;
import weka.clusterers.forOPTICSAndDBScan.Utils.EpsilonRange_ListElement;
import weka.clusterers.forOPTICSAndDBScan.Utils.UpdateQueue;
import weka.clusterers.forOPTICSAndDBScan.Utils.UpdateQueueElement;
import weka.core.Capabilities;
import weka.core.FastVector;
import weka.core.Instance;
import weka.core.Instances;
import weka.core.Option;
import weka.core.OptionHandler;
import weka.core.RevisionUtils;
import weka.core.TechnicalInformation;
import weka.core.TechnicalInformationHandler;
import weka.core.Utils;
import weka.core.Capabilities.Capability;
import weka.core.TechnicalInformation.Field;
import weka.core.TechnicalInformation.Type;
import weka.filters.Filter;
import weka.filters.unsupervised.attribute.ReplaceMissingValues;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.ObjectOutputStream;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.text.DecimalFormat;
import java.util.Calendar;
import java.util.Enumeration;
import java.util.GregorianCalendar;
import java.util.Iterator;
import java.util.List;
import java.util.Vector;

/**
 <!-- globalinfo-start -->
 * Mihael Ankerst, Markus M. Breunig, Hans-Peter Kriegel, Joerg Sander: OPTICS: Ordering Points To Identify the Clustering Structure. In: ACM SIGMOD International Conference on Management of Data, 49-60, 1999.
 * <p/>
 <!-- globalinfo-end -->
 *
 <!-- technical-bibtex-start -->
 * BibTeX:
 * <pre>
 * &#64;inproceedings{Ankerst1999,
 *    author = {Mihael Ankerst and Markus M. Breunig and Hans-Peter Kriegel and Joerg Sander},
 *    booktitle = {ACM SIGMOD International Conference on Management of Data},
 *    pages = {49-60},
 *    publisher = {ACM Press},
 *    title = {OPTICS: Ordering Points To Identify the Clustering Structure},
 *    year = {1999}
 * }
 * </pre>
 * <p/>
 <!-- technical-bibtex-end -->
 *
 <!-- options-start -->
 * Valid options are: <p/>
 * 
 * <pre> -E &lt;double&gt;
 *  epsilon (default = 0.9)</pre>
 * 
 * <pre> -M &lt;int&gt;
 *  minPoints (default = 6)</pre>
 * 
 * <pre> -I &lt;String&gt;
 *  index (database) used for OPTICS (default = weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase)</pre>
 * 
 * <pre> -D &lt;String&gt;
 *  distance-type (default = weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclidianDataObject)</pre>
 * 
 * <pre> -F
 *  write results to OPTICS_#TimeStamp#.TXT - File</pre>
 * 
 * <pre> -no-gui
 *  suppress the display of the GUI after building the clusterer</pre>
 * 
 * <pre> -db-output &lt;file&gt;
 *  The file to save the generated database to. If a directory
 *  is provided, the database doesn't get saved.
 *  The generated file can be viewed with the OPTICS Visualizer:
 *    java weka.clusterers.forOPTICSAndDBScan.OPTICS_GUI.OPTICS_Visualizer [file.ser]
 *  (default: .)</pre>
 * 
 <!-- options-end -->
 *
 * @author Matthias Schubert (schubert@dbs.ifi.lmu.de)
 * @author Zhanna Melnikova-Albrecht (melnikov@cip.ifi.lmu.de)
 * @author Rainer Holzmann (holzmann@cip.ifi.lmu.de)
 * @version $Revision: 5488 $
 */
public class OPTICS 
    extends AbstractClusterer 
    implements OptionHandler, TechnicalInformationHandler {

    /** for serialization */
    static final long serialVersionUID = 274552680222105221L;
  
    /**
     * Specifies the radius for a range-query
     */
    private double epsilon = 0.9;

    /**
     * Specifies the density (the range-query must contain at least minPoints DataObjects)
     */
    private int minPoints = 6;

    /**
     * Replace missing values in training instances
     */
    private ReplaceMissingValues replaceMissingValues_Filter;

    /**
     * Holds the number of clusters generated
     */
    private int numberOfGeneratedClusters;

    /**
     * Holds the distance-type that is used
     * (default = weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclidianDataObject)
     */
    private String database_distanceType = "weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclidianDataObject";

    /**
     * Holds the type of the used database
     * (default = weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase)
     */
    private String database_Type = "weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase";

    /**
     * The database that is used for OPTICS
     */
    private Database database;

    /**
     * Holds the time-value (seconds) for the duration of the clustering-process
     */
    private double elapsedTime;

    /**
     * Flag that indicates if the results are written to a file or not
     */
    private boolean writeOPTICSresults = false;

    /**
     * Holds the ClusterOrder (dataObjects with their r_dist and c_dist) for the GUI
     */
    private FastVector resultVector;

    /** whether to display the GUI after building the clusterer or not. */
    private boolean showGUI = true;
    
    /** the file to save the generated database object to. */
    private File databaseOutput = new File(".");
    
    // *****************************************************************************************************************
    // constructors
    // *****************************************************************************************************************

    // *****************************************************************************************************************
    // methods
    // *****************************************************************************************************************

    /**
     * Returns default capabilities of the clusterer.
     *
     * @return      the capabilities of this clusterer
     */
    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.DATE_ATTRIBUTES);
      result.enable(Capability.MISSING_VALUES);

      return result;
    }

    /**
     * Generate Clustering via OPTICS
     * @param instances The instances that need to be clustered
     * @throws java.lang.Exception If clustering was not successful
     */
    public void buildClusterer(Instances instances) throws Exception {
        // can clusterer handle the data?
        getCapabilities().testWithFail(instances);

        resultVector = new FastVector();
        long time_1 = System.currentTimeMillis();

        numberOfGeneratedClusters = 0;

        replaceMissingValues_Filter = new ReplaceMissingValues();
        replaceMissingValues_Filter.setInputFormat(instances);
        Instances filteredInstances = Filter.useFilter(instances, replaceMissingValues_Filter);

        database = databaseForName(getDatabase_Type(), filteredInstances);
        for (int i = 0; i < database.getInstances().numInstances(); i++) {
            DataObject dataObject = dataObjectForName(getDatabase_distanceType(),
                    database.getInstances().instance(i),
                    Integer.toString(i),
                    database);
            database.insert(dataObject);
        }
        database.setMinMaxValues();

        UpdateQueue seeds = new UpdateQueue();

        /** OPTICS-Begin */
        Iterator iterator = database.dataObjectIterator();
        while (iterator.hasNext()) {
            DataObject dataObject = (DataObject) iterator.next();
            if (!dataObject.isProcessed()) {
                expandClusterOrder(dataObject, seeds);
            }
        }

        long time_2 = System.currentTimeMillis();
        elapsedTime = (double) (time_2 - time_1) / 1000.0;

        if (writeOPTICSresults) {
            String fileName = "";
            GregorianCalendar gregorianCalendar = new GregorianCalendar();
            String timeStamp = gregorianCalendar.get(Calendar.DAY_OF_MONTH) + "-" +
                    (gregorianCalendar.get(Calendar.MONTH) + 1) +
                    "-" + gregorianCalendar.get(Calendar.YEAR) +
                    "--" + gregorianCalendar.get(Calendar.HOUR_OF_DAY) +
                    "-" + gregorianCalendar.get(Calendar.MINUTE) +
                    "-" + gregorianCalendar.get(Calendar.SECOND);
            fileName = "OPTICS_" + timeStamp + ".TXT";

            FileWriter fileWriter = new FileWriter(fileName);
            BufferedWriter bufferedOPTICSWriter = new BufferedWriter(fileWriter);
            for (int i = 0; i < resultVector.size(); i++) {
                bufferedOPTICSWriter.write(format_dataObject((DataObject) resultVector.elementAt(i)));
            }
            bufferedOPTICSWriter.flush();
            bufferedOPTICSWriter.close();
        }

        // explicit file provided to write the generated database to?
        if (!databaseOutput.isDirectory()) {
          try {
            FileOutputStream fos = new FileOutputStream(databaseOutput);
            ObjectOutputStream oos = new ObjectOutputStream(fos);
            oos.writeObject(getSERObject());
            oos.flush();
            oos.close();
            fos.close();
          }
          catch (Exception e) {
            System.err.println(
        	"Error writing generated database to file '" + getDatabaseOutput() + "': " 
        	+ e);
            e.printStackTrace();
          }
        }
        
        if (showGUI)
          new OPTICS_Visualizer(getSERObject(), "OPTICS Visualizer - Main Window");
    }

    /**
     * Expands the ClusterOrder for this dataObject
     * @param dataObject Start-DataObject
     * @param seeds SeedList that stores dataObjects with reachability-distances
     */
    private void expandClusterOrder(DataObject dataObject, UpdateQueue seeds) {
        List list = database.coreDistance(getMinPoints(), getEpsilon(), dataObject);
        List epsilonRange_List = (List) list.get(1);
        dataObject.setReachabilityDistance(DataObject.UNDEFINED);
        dataObject.setCoreDistance(((Double) list.get(2)).doubleValue());
        dataObject.setProcessed(true);

        resultVector.addElement(dataObject);

        if (dataObject.getCoreDistance() != DataObject.UNDEFINED) {
            update(seeds, epsilonRange_List, dataObject);
            while (seeds.hasNext()) {
                UpdateQueueElement updateQueueElement = seeds.next();
                DataObject currentDataObject = (DataObject) updateQueueElement.getObject();
                currentDataObject.setReachabilityDistance(updateQueueElement.getPriority());
                List list_1 = database.coreDistance(getMinPoints(), getEpsilon(), currentDataObject);
                List epsilonRange_List_1 = (List) list_1.get(1);
                currentDataObject.setCoreDistance(((Double) list_1.get(2)).doubleValue());
                currentDataObject.setProcessed(true);

                resultVector.addElement(currentDataObject);

                if (currentDataObject.getCoreDistance() != DataObject.UNDEFINED) {
                    update(seeds, epsilonRange_List_1, currentDataObject);
                }
            }
        }
    }

    /**
     * Wraps the dataObject into a String, that contains the dataObject's key, the dataObject itself,
     * the coreDistance and its reachabilityDistance in a formatted manner.
     * @param dataObject The dataObject that is wrapped into a formatted string.
     * @return String Formatted string
     */
    private String format_dataObject(DataObject dataObject) {
        StringBuffer stringBuffer = new StringBuffer();

        stringBuffer.append("(" + Utils.doubleToString(Double.parseDouble(dataObject.getKey()),
                (Integer.toString(database.size()).length()), 0) + ".) "
                + Utils.padRight(dataObject.toString(), 40) + "  -->  c_dist: " +

                ((dataObject.getCoreDistance() == DataObject.UNDEFINED) ?
                Utils.padRight("UNDEFINED", 12) :
                Utils.padRight(Utils.doubleToString(dataObject.getCoreDistance(), 2, 3), 12)) +

                " r_dist: " +
                ((dataObject.getReachabilityDistance() == DataObject.UNDEFINED) ?
                Utils.padRight("UNDEFINED", 12) :
                Utils.doubleToString(dataObject.getReachabilityDistance(), 2, 3)) + "\n");

        return stringBuffer.toString();
    }

    /**
     * Updates reachability-distances in the Seeds-List
     * @param seeds UpdateQueue that holds DataObjects with their corresponding reachability-distances
     * @param epsilonRange_list List of DataObjects that were found in epsilon-range of centralObject
     * @param centralObject
     */
    private void update(UpdateQueue seeds, List epsilonRange_list, DataObject centralObject) {
        double coreDistance = centralObject.getCoreDistance();
        double new_r_dist = DataObject.UNDEFINED;

        for (int i = 0; i < epsilonRange_list.size(); i++) {
            EpsilonRange_ListElement listElement = (EpsilonRange_ListElement) epsilonRange_list.get(i);
            DataObject neighbourhood_object = listElement.getDataObject();
            if (!neighbourhood_object.isProcessed()) {
                new_r_dist = Math.max(coreDistance, listElement.getDistance());
                seeds.add(new_r_dist, neighbourhood_object, neighbourhood_object.getKey());
            }
        }
    }

    /**
     * Classifies a given instance.
     *
     * @param instance The instance to be assigned to a cluster
     * @return int The number of the assigned cluster as an integer
     * @throws java.lang.Exception If instance could not be clustered
     * successfully
     */
    public int clusterInstance(Instance instance) throws Exception {
        throw new Exception();
    }

    /**
     * Returns the number of clusters.
     *
     * @return int The number of clusters generated for a training dataset.
     * @throws java.lang.Exception If number of clusters could not be returned
     * successfully
     */
    public int numberOfClusters() throws Exception {
        return numberOfGeneratedClusters;
    }

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

        vector.addElement(
            new Option(
        	"\tepsilon (default = 0.9)",
        	"E", 1, "-E <double>"));
        
        vector.addElement(
            new Option("\tminPoints (default = 6)",
        	"M", 1, "-M <int>"));
        
        vector.addElement(
            new Option(
        	"\tindex (database) used for OPTICS (default = weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase)",
        	"I", 1, "-I <String>"));
        
        vector.addElement(
            new Option(
        	"\tdistance-type (default = weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclidianDataObject)",
        	"D", 1, "-D <String>"));
        
        vector.addElement(
            new Option(
        	"\twrite results to OPTICS_#TimeStamp#.TXT - File",
        	"F", 0, "-F"));
        
        vector.addElement(
            new Option(
        	"\tsuppress the display of the GUI after building the clusterer",
        	"no-gui", 0, "-no-gui"));
        
        vector.addElement(
            new Option(
        	"\tThe file to save the generated database to. If a directory\n"
        	+ "\tis provided, the database doesn't get saved.\n"
        	+ "\tThe generated file can be viewed with the OPTICS Visualizer:\n"
        	+ "\t  java " + OPTICS_Visualizer.class.getName() + " [file.ser]\n"
        	+ "\t(default: .)",
        	"db-output", 1, "-db-output <file>"));
        
        return vector.elements();
    }

    /**
     * Sets the OptionHandler's options using the given list. All options
     * will be set (or reset) during this call (i.e. incremental setting
     * of options is not possible). <p/>
     * 
     <!-- options-start -->
     * Valid options are: <p/>
     * 
     * <pre> -E &lt;double&gt;
     *  epsilon (default = 0.9)</pre>
     * 
     * <pre> -M &lt;int&gt;
     *  minPoints (default = 6)</pre>
     * 
     * <pre> -I &lt;String&gt;
     *  index (database) used for OPTICS (default = weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase)</pre>
     * 
     * <pre> -D &lt;String&gt;
     *  distance-type (default = weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclidianDataObject)</pre>
     * 
     * <pre> -F
     *  write results to OPTICS_#TimeStamp#.TXT - File</pre>
     * 
     * <pre> -no-gui
     *  suppress the display of the GUI after building the clusterer</pre>
     * 
     * <pre> -db-output &lt;file&gt;
     *  The file to save the generated database to. If a directory
     *  is provided, the database doesn't get saved.
     *  The generated file can be viewed with the OPTICS Visualizer:
     *    java weka.clusterers.forOPTICSAndDBScan.OPTICS_GUI.OPTICS_Visualizer [file.ser]
     *  (default: .)</pre>
     * 
     <!-- options-end -->
     *
     * @param options The list of options as an array of strings
     * @throws java.lang.Exception If an option is not supported
     */
    public void setOptions(String[] options) throws Exception {
        String optionString = Utils.getOption('E', options);
        if (optionString.length() != 0)
            setEpsilon(Double.parseDouble(optionString));
        else
            setEpsilon(0.9);

        optionString = Utils.getOption('M', options);
        if (optionString.length() != 0)
            setMinPoints(Integer.parseInt(optionString));
        else
            setMinPoints(6);

        optionString = Utils.getOption('I', options);
        if (optionString.length() != 0)
            setDatabase_Type(optionString);
        else
            setDatabase_Type(weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase.class.getName());

        optionString = Utils.getOption('D', options);
        if (optionString.length() != 0)
            setDatabase_distanceType(optionString);
        else
            setDatabase_distanceType(weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclidianDataObject.class.getName());

        setWriteOPTICSresults(Utils.getFlag('F', options));

        setShowGUI(!Utils.getFlag("no-gui", options));

        optionString = Utils.getOption("db-output", options);
        if (optionString.length() != 0)
            setDatabaseOutput(new File(optionString));
        else
            setDatabaseOutput(new File("."));
    }

    /**
     * Gets the current option settings for the OptionHandler.
     *
     * @return String[] The list of current option settings as an array of strings
     */
    public String[] getOptions() {
        Vector<String>	result;
        
        result = new Vector<String>();
        
        result.add("-E");
        result.add("" + getEpsilon());
        
        result.add("-M");
        result.add("" + getMinPoints());
        
        result.add("-I");
        result.add("" + getDatabase_Type());
        
        result.add("-D");
        result.add("" + getDatabase_distanceType());

        if (getWriteOPTICSresults())
          result.add("-F");

        if (!getShowGUI())
          result.add("-no-gui");
        
        result.add("-db-output");
        result.add("" + getDatabaseOutput());
        
        return result.toArray(new String[result.size()]);
    }

    /**
     * Returns a new Class-Instance of the specified database
     * @param database_Type String of the specified database
     * @param instances Instances that were delivered from WEKA
     * @return Database New constructed Database
     */
    public Database databaseForName(String database_Type, Instances instances) {
        Object o = null;

        Constructor co = null;
        try {
            co = (Class.forName(database_Type)).getConstructor(new Class[]{Instances.class});
            o = co.newInstance(new Object[]{instances});
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }

        return (Database) o;
    }

    /**
     * Returns a new Class-Instance of the specified database
     * @param database_distanceType String of the specified distance-type
     * @param instance The original instance that needs to hold by this DataObject
     * @param key Key for this DataObject
     * @param database Link to the database
     * @return DataObject New constructed DataObject
     */
    public DataObject dataObjectForName(String database_distanceType, Instance instance, String key, Database database) {
        Object o = null;

        Constructor co = null;
        try {
            co = (Class.forName(database_distanceType)).
                    getConstructor(new Class[]{Instance.class, String.class, Database.class});
            o = co.newInstance(new Object[]{instance, key, database});
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }

        return (DataObject) o;
    }

    /**
     * Sets a new value for minPoints
     * @param minPoints MinPoints
     */
    public void setMinPoints(int minPoints) {
        this.minPoints = minPoints;
    }

    /**
     * Sets a new value for epsilon
     * @param epsilon Epsilon
     */
    public void setEpsilon(double epsilon) {
        this.epsilon = epsilon;
    }

    /**
     * Returns the value of epsilon
     * @return double Epsilon
     */
    public double getEpsilon() {
        return epsilon;
    }

    /**
     * Returns the value of minPoints
     * @return int MinPoints
     */
    public int getMinPoints() {
        return minPoints;
    }

    /**
     * Returns the distance-type
     * @return String Distance-type
     */
    public String getDatabase_distanceType() {
        return database_distanceType;
    }

    /**
     * Returns the type of the used index (database)
     * @return String Index-type
     */
    public String getDatabase_Type() {
        return database_Type;
    }

    /**
     * Sets a new distance-type
     * @param database_distanceType The new distance-type
     */
    public void setDatabase_distanceType(String database_distanceType) {
        this.database_distanceType = database_distanceType;
    }

    /**
     * Sets a new database-type
     * @param database_Type The new database-type
     */
    public void setDatabase_Type(String database_Type) {
        this.database_Type = database_Type;
    }

    /**
     * Returns the flag for writing actions
     * @return writeOPTICSresults (flag)
     */
    public boolean getWriteOPTICSresults() {
        return writeOPTICSresults;
    }

    /**
     * Sets the flag for writing actions
     * @param writeOPTICSresults Results are written to a file if the flag is set
     */
    public void setWriteOPTICSresults(boolean writeOPTICSresults) {
        this.writeOPTICSresults = writeOPTICSresults;
    }

    /**
     * Returns the flag for showing the OPTICS visualizer GUI.
     * 
     * @return 		true if the GUI is displayed
     */
    public boolean getShowGUI() {
        return showGUI;
    }

    /**
     * Sets the flag for displaying the GUI.
     * 
     * @param value 	if true, then the OPTICS visualizer GUI will be 
     * 			displayed after building the clusterer
     */
    public void setShowGUI(boolean value) {
        showGUI = value;
    }

    /**
     * Returns the file to save the database to - if directory, database is not
     * saved.
     * 
     * @return 		the file to save the database to a directory if saving
     * 			is ignored
     */
    public File getDatabaseOutput() {
        return databaseOutput;
    }

    /**
     * Sets the the file to save the generated database to. If a directory
     * is provided, the datbase doesn't get saved.
     * 
     * @param value 	the file to save the database to or a directory if
     * 			saving is to be ignored
     */
    public void setDatabaseOutput(File value) {
        databaseOutput = value;
    }

    /**
     * Returns the resultVector
     * @return resultVector
     */
    public FastVector getResultVector() {
        return resultVector;
    }

    /**
     * Returns the tip text for this property
     * @return tip text for this property suitable for
     * displaying in the explorer/experimenter gui
     */
    public String epsilonTipText() {
        return "radius of the epsilon-range-queries";
    }

    /**
     * Returns the tip text for this property
     * @return tip text for this property suitable for
     * displaying in the explorer/experimenter gui
     */
    public String minPointsTipText() {
        return "minimun number of DataObjects required in an epsilon-range-query";
    }

    /**
     * Returns the tip text for this property
     * @return tip text for this property suitable for
     * displaying in the explorer/experimenter gui
     */
    public String database_TypeTipText() {
        return "used database";
    }

    /**
     * Returns the tip text for this property
     * @return tip text for this property suitable for
     * displaying in the explorer/experimenter gui
     */
    public String database_distanceTypeTipText() {
        return "used distance-type";
    }

    /**
     * Returns the tip text for this property
     * @return tip text for this property suitable for
     * displaying in the explorer/experimenter gui
     */
    public String writeOPTICSresultsTipText() {
        return "if the -F option is set, the results are written to OPTICS_#TimeStamp#.TXT";
    }

    /**
     * Returns the tip text for this property.
     * 
     * @return 		tip text for this property suitable for
     * 			displaying in the explorer/experimenter gui
     */
    public String showGUITipText() {
        return "Defines whether the OPTICS Visualizer is displayed after the clusterer has been built or not.";
    }

    /**
     * Returns the tip text for this property.
     * 
     * @return 		tip text for this property suitable for
     * 			displaying in the explorer/experimenter gui
     */
    public String databaseOutputTipText() {
        return 
            "The optional output file for the generated database object - can "
          + "be viewed with the OPTICS Visualizer.\n"
          + "java " + OPTICS_Visualizer.class.getName() + " [file.ser]";
    }

    /**
     * Returns a string describing this DataMining-Algorithm
     * @return String Information for the gui-explorer
     */
    public String globalInfo() {
        return getTechnicalInformation().toString();
    }

    /**
     * Returns an instance of a TechnicalInformation object, containing 
     * detailed information about the technical background of this class,
     * e.g., paper reference or book this class is based on.
     * 
     * @return the technical information about this class
     */
    public TechnicalInformation getTechnicalInformation() {
      TechnicalInformation 	result;
      
      result = new TechnicalInformation(Type.INPROCEEDINGS);
      result.setValue(Field.AUTHOR, "Mihael Ankerst and Markus M. Breunig and Hans-Peter Kriegel and Joerg Sander");
      result.setValue(Field.TITLE, "OPTICS: Ordering Points To Identify the Clustering Structure");
      result.setValue(Field.BOOKTITLE, "ACM SIGMOD International Conference on Management of Data");
      result.setValue(Field.YEAR, "1999");
      result.setValue(Field.PAGES, "49-60");
      result.setValue(Field.PUBLISHER, "ACM Press");
      
      return result;
    }

    /**
     * Returns the internal database
     * 
     * @return the internal database
     */
    public SERObject getSERObject() {
        SERObject serObject = new SERObject(resultVector,
                database.size(),
                database.getInstances().numAttributes(),
                getEpsilon(),
                getMinPoints(),
                writeOPTICSresults,
                getDatabase_Type(),
                getDatabase_distanceType(),
                numberOfGeneratedClusters,
                Utils.doubleToString(elapsedTime, 3, 3));
        return serObject;
    }

    /**
     * Returns a description of the clusterer
     * 
     * @return the clusterer as string
     */
    public String toString() {
        StringBuffer stringBuffer = new StringBuffer();
        stringBuffer.append("OPTICS clustering results\n" +
                "============================================================================================\n\n");
        stringBuffer.append("Clustered DataObjects: " + database.size() + "\n");
        stringBuffer.append("Number of attributes: " + database.getInstances().numAttributes() + "\n");
        stringBuffer.append("Epsilon: " + getEpsilon() + "; minPoints: " + getMinPoints() + "\n");
        stringBuffer.append("Write results to file: " + (writeOPTICSresults ? "yes" : "no") + "\n");
        stringBuffer.append("Index: " + getDatabase_Type() + "\n");
        stringBuffer.append("Distance-type: " + getDatabase_distanceType() + "\n");
        stringBuffer.append("Number of generated clusters: " + numberOfGeneratedClusters + "\n");
        DecimalFormat decimalFormat = new DecimalFormat(".##");
        stringBuffer.append("Elapsed time: " + decimalFormat.format(elapsedTime) + "\n\n");

        for (int i = 0; i < resultVector.size(); i++) {
            stringBuffer.append(format_dataObject((DataObject) resultVector.elementAt(i)));
        }
        return stringBuffer.toString() + "\n";
    }
    
    /**
     * Returns the revision string.
     * 
     * @return		the revision
     */
    public String getRevision() {
      return RevisionUtils.extract("$Revision: 5488 $");
    }

    /**
     * Main Method for testing OPTICS
     * @param args Valid parameters are: 'E' epsilon (default = 0.9); 'M' minPoints (default = 6);
     *                                   'I' index-type (default = weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase);
     *                                   'D' distance-type (default = weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclidianDataObject);
     *                                   'F' write results to OPTICS_#TimeStamp#.TXT - File
     */
    public static void main(String[] args) {
        runClusterer(new OPTICS(), args);
    }
}