weka.clusterers.DBSCAN Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of weka-stable Show documentation
Show all versions of weka-stable Show documentation
The Waikato Environment for Knowledge Analysis (WEKA), a machine
learning workbench. This is the stable version. Apart from bugfixes, this version
does not receive any other updates.
/*
* 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 3 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, see
*
* Martin Ester, Hans-Peter Kriegel, Joerg Sander, Xiaowei Xu: A Density-Based Algorithm for Discovering Clusters in Large Spatial Databases with Noise. In: Second International Conference on Knowledge Discovery and Data Mining, 226-231, 1996.
*
*
* BibTeX:
*
* @inproceedings{Ester1996,
* author = {Martin Ester and Hans-Peter Kriegel and Joerg Sander and Xiaowei Xu},
* booktitle = {Second International Conference on Knowledge Discovery and Data Mining},
* editor = {Evangelos Simoudis and Jiawei Han and Usama M. Fayyad},
* pages = {226-231},
* publisher = {AAAI Press},
* title = {A Density-Based Algorithm for Discovering Clusters in Large Spatial Databases with Noise},
* year = {1996}
* }
*
*
*
* Valid options are:
*
* -E <double>
* epsilon (default = 0.9)
*
* -M <int>
* minPoints (default = 6)
*
* -I <String>
* index (database) used for DBSCAN (default = weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase)
*
* -D <String>
* distance-type (default = weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclideanDataObject)
*
*
* @author Matthias Schubert ([email protected])
* @author Zhanna Melnikova-Albrecht ([email protected])
* @author Rainer Holzmann ([email protected])
* @version $Revision: 9434 $
*/
public class DBSCAN
extends AbstractClusterer
implements OptionHandler, TechnicalInformationHandler {
/** for serialization */
static final long serialVersionUID = -1666498248451219728L;
/**
* 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.EuclideanDataObject)
*/
private String database_distanceType = "weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclideanDataObject";
/**
* 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 DBSCAN
*/
private Database database;
/**
* Holds the current clusterID
*/
private int clusterID;
/**
* Counter for the processed instances
*/
private int processed_InstanceID;
/**
* Holds the time-value (seconds) for the duration of the clustering-process
*/
private double elapsedTime;
/**
* 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;
}
// *****************************************************************************************************************
// constructors
// *****************************************************************************************************************
// *****************************************************************************************************************
// methods
// *****************************************************************************************************************
/**
* Generate Clustering via DBSCAN
* @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);
long time_1 = System.currentTimeMillis();
processed_InstanceID = 0;
numberOfGeneratedClusters = 0;
clusterID = 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();
Iterator iterator = database.dataObjectIterator();
while (iterator.hasNext()) {
DataObject dataObject = (DataObject) iterator.next();
if (dataObject.getClusterLabel() == DataObject.UNCLASSIFIED) {
if (expandCluster(dataObject)) {
clusterID++;
numberOfGeneratedClusters++;
}
}
}
long time_2 = System.currentTimeMillis();
elapsedTime = (double) (time_2 - time_1) / 1000.0;
}
/**
* Assigns this dataObject to a cluster or remains it as NOISE
* @param dataObject The DataObject that needs to be assigned
* @return true, if the DataObject could be assigned, else false
*/
private boolean expandCluster(DataObject dataObject) {
List seedList = database.epsilonRangeQuery(getEpsilon(), dataObject);
/** dataObject is NO coreObject */
if (seedList.size() < getMinPoints()) {
dataObject.setClusterLabel(DataObject.NOISE);
return false;
}
/** dataObject is coreObject */
for (int i = 0; i < seedList.size(); i++) {
DataObject seedListDataObject = (DataObject) seedList.get(i);
/** label this seedListDataObject with the current clusterID, because it is in epsilon-range */
seedListDataObject.setClusterLabel(clusterID);
if (seedListDataObject.equals(dataObject)) {
seedList.remove(i);
i--;
}
}
/** Iterate the seedList of the startDataObject */
for (int j = 0; j < seedList.size(); j++) {
DataObject seedListDataObject = (DataObject) seedList.get(j);
List seedListDataObject_Neighbourhood = database.epsilonRangeQuery(getEpsilon(), seedListDataObject);
/** seedListDataObject is coreObject */
if (seedListDataObject_Neighbourhood.size() >= getMinPoints()) {
for (int i = 0; i < seedListDataObject_Neighbourhood.size(); i++) {
DataObject p = (DataObject) seedListDataObject_Neighbourhood.get(i);
if (p.getClusterLabel() == DataObject.UNCLASSIFIED || p.getClusterLabel() == DataObject.NOISE) {
if (p.getClusterLabel() == DataObject.UNCLASSIFIED) {
seedList.add(p);
}
p.setClusterLabel(clusterID);
}
}
}
seedList.remove(j);
j--;
}
return true;
}
/**
* 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 {
if (processed_InstanceID >= database.size()) processed_InstanceID = 0;
int cnum = (database.getDataObject(Integer.toString(processed_InstanceID++))).getClusterLabel();
if (cnum == DataObject.NOISE)
throw new Exception();
else
return cnum;
}
/**
* 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 "));
vector.addElement(
new Option("\tminPoints (default = 6)",
"M",
1,
"-M "));
vector.addElement(
new Option("\tindex (database) used for DBSCAN (default = weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase)",
"I",
1,
"-I "));
vector.addElement(
new Option("\tdistance-type (default = weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclideanDataObject)",
"D",
1,
"-D "));
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).
*
* Valid options are:
*
* -E <double>
* epsilon (default = 0.9)
*
* -M <int>
* minPoints (default = 6)
*
* -I <String>
* index (database) used for DBSCAN (default = weka.clusterers.forOPTICSAndDBScan.Databases.SequentialDatabase)
*
* -D <String>
* distance-type (default = weka.clusterers.forOPTICSAndDBScan.DataObjects.EuclideanDataObject)
*
*
* @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));
}
optionString = Utils.getOption('M', options);
if (optionString.length() != 0) {
setMinPoints(Integer.parseInt(optionString));
}
optionString = Utils.getOption('I', options);
if (optionString.length() != 0) {
setDatabase_Type(optionString);
}
optionString = Utils.getOption('D', options);
if (optionString.length() != 0) {
setDatabase_distanceType(optionString);
}
}
/**
* Gets the current option settings for the OptionHandler.
*
* @return String[] The list of current option settings as an array of strings
*/
public String[] getOptions() {
String[] options = new String[8];
int current = 0;
options[current++] = "-E";
options[current++] = "" + getEpsilon();
options[current++] = "-M";
options[current++] = "" + getMinPoints();
options[current++] = "-I";
options[current++] = "" + getDatabase_Type();
options[current++] = "-D";
options[current++] = "" + getDatabase_distanceType();
return options;
}
/**
* 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 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 a string describing this DataMining-Algorithm
* @return String Information for the gui-explorer
*/
public String globalInfo() {
return "Basic implementation of DBSCAN clustering algorithm that should "
+ "*not* be used as a reference for runtime benchmarks: more sophisticated "
+ "implementations exist! Clustering of new instances is not supported. More info:\n\n "
+ 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, "Martin Ester and Hans-Peter Kriegel and Joerg Sander and Xiaowei Xu");
result.setValue(Field.TITLE, "A Density-Based Algorithm for Discovering Clusters in Large Spatial Databases with Noise");
result.setValue(Field.BOOKTITLE, "Second International Conference on Knowledge Discovery and Data Mining");
result.setValue(Field.EDITOR, "Evangelos Simoudis and Jiawei Han and Usama M. Fayyad");
result.setValue(Field.YEAR, "1996");
result.setValue(Field.PAGES, "226-231");
result.setValue(Field.PUBLISHER, "AAAI Press");
return result;
}
/**
* Returns a description of the clusterer
*
* @return a string representation of the clusterer
*/
public String toString() {
StringBuffer stringBuffer = new StringBuffer();
stringBuffer.append("DBSCAN 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("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 < database.size(); i++) {
DataObject dataObject = database.getDataObject(Integer.toString(i));
stringBuffer.append("(" + Utils.doubleToString(Double.parseDouble(dataObject.getKey()),
(Integer.toString(database.size()).length()), 0) + ".) "
+ Utils.padRight(dataObject.toString(), 69) + " --> " +
((dataObject.getClusterLabel() == DataObject.NOISE) ?
"NOISE\n" : dataObject.getClusterLabel() + "\n"));
}
return stringBuffer.toString() + "\n";
}
/**
* Returns the revision string.
*
* @return the revision
*/
public String getRevision() {
return RevisionUtils.extract("$Revision: 9434 $");
}
/**
* Main Method for testing DBSCAN
* @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.EuclideanDataObject);
*/
public static void main(String[] args) {
runClusterer(new DBSCAN(), args);
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy