Java tutorial
/* * 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 <http://www.gnu.org/licenses/>. */ /* * 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 pk.lums.edu.sma.processing.ml.DBSCAN; import java.io.Serializable; import weka.core.Attribute; import weka.core.Instance; import weka.core.RevisionHandler; import weka.core.RevisionUtils; import weka.core.Utils; /** * <p> * EuclideanDataObject.java <br/> * Authors: Rainer Holzmann, Zhanna Melnikova-Albrecht, Matthias Schubert <br/> * Date: Aug 19, 2004 <br/> * Time: 5:50:22 PM <br/> * $ Revision 1.4 $ <br/> * </p> * * @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: 8108 $ */ public class EuclideanDataObject implements DataObject, Serializable, RevisionHandler { /** for serialization */ private static final long serialVersionUID = -4408119914898291075L; /** * Holds the original instance */ private Instance instance; /** * Holds the (unique) key that is associated with this DataObject */ private String key; /** * Holds the ID of the cluster, to which this DataObject is assigned */ private int clusterID; /** * Holds the status for this DataObject (true, if it has been processed, * else false) */ private boolean processed; /** * Holds the coreDistance for this DataObject */ private double c_dist; /** * Holds the reachabilityDistance for this DataObject */ private double r_dist; /** * Holds the database, that is the keeper of this DataObject */ private Database database; // ***************************************************************************************************************** // constructors // ***************************************************************************************************************** /** * Constructs a new DataObject. The original instance is kept as * instance-variable * * @param originalInstance * the original instance */ public EuclideanDataObject(Instance originalInstance, String key, Database database) { this.database = database; this.key = key; instance = originalInstance; clusterID = DataObject.UNCLASSIFIED; processed = false; c_dist = DataObject.UNDEFINED; r_dist = DataObject.UNDEFINED; } // ***************************************************************************************************************** // methods // ***************************************************************************************************************** /** * Compares two DataObjects in respect to their attribute-values * * @param dataObject * The DataObject, that is compared with this.dataObject; now * assumed to be of the same type and with the same structure * @return Returns true, if the DataObjects correspond in each value, else * returns false */ public boolean equals(DataObject dataObject) { if (this == dataObject) return true; Instance firstInstance = getInstance(); Instance secondInstance = dataObject.getInstance(); int firstNumValues = firstInstance.numValues(); int secondNumValues = secondInstance.numValues(); int numAttributes = firstInstance.numAttributes(); int firstI, secondI; for (int p1 = 0, p2 = 0; p1 < firstNumValues || p2 < secondNumValues;) { if (p1 >= firstNumValues) { firstI = numAttributes; } else { firstI = firstInstance.index(p1); } if (p2 >= secondNumValues) { secondI = numAttributes; } else { secondI = secondInstance.index(p2); } if (firstI == secondI) { if (firstInstance.valueSparse(p1) != secondInstance.valueSparse(p2)) { return false; } p1++; p2++; } else if (firstI > secondI) { if (0 != secondInstance.valueSparse(p2)) { return false; } p2++; } else { if (0 != firstInstance.valueSparse(p1)) { return false; } p1++; } } return true; } /** * Calculates the euclidian-distance between dataObject and this.dataObject * * @param dataObject * The DataObject, that is used for distance-calculation with * this.dataObject; now assumed to be of the same type and with * the same structure * @return double-value The euclidian-distance between dataObject and * this.dataObject */ public double distance(DataObject dataObject) { double dist = 0.0; Instance firstInstance = getInstance(); Instance secondInstance = dataObject.getInstance(); int firstNumValues = firstInstance.numValues(); int secondNumValues = secondInstance.numValues(); int numAttributes = firstInstance.numAttributes(); int firstI, secondI; for (int p1 = 0, p2 = 0; p1 < firstNumValues || p2 < secondNumValues;) { if (p1 >= firstNumValues) { firstI = numAttributes; } else { firstI = firstInstance.index(p1); } if (p2 >= secondNumValues) { secondI = numAttributes; } else { secondI = secondInstance.index(p2); } double cDistance = 0; if (firstI == secondI) { cDistance = computeDistance(firstI, firstInstance.valueSparse(p1), secondInstance.valueSparse(p2)); p1++; p2++; } else if (firstI > secondI) { cDistance = computeDistance(secondI, 0, secondInstance.valueSparse(p2)); p2++; } else { cDistance = computeDistance(firstI, firstInstance.valueSparse(p1), 0); p1++; } dist += cDistance * cDistance; } return Math.sqrt(dist); } /** * Performs euclidian-distance-calculation between two given values * * @param index * of the attribute within the DataObject's instance * @param v * value_1 * @param v1 * value_2 * @return double norm-distance between value_1 and value_2 */ private double computeDistance(int index, double v, double v1) { switch (getInstance().attribute(index).type()) { case Attribute.NOMINAL: return (((int) v != (int) v1)) ? 1 : 0; case Attribute.NUMERIC: return norm(v, index) - norm(v1, index); default: return 0; } } /** * Normalizes a given value of a numeric attribute. * * @param x * the value to be normalized * @param i * the attribute's index */ private double norm(double x, int i) { if (Double.isNaN(database.getAttributeMinValues()[i]) || Utils.eq(database.getAttributeMaxValues()[i], database.getAttributeMinValues()[i])) { return 0; } else { return (x - database.getAttributeMinValues()[i]) / (database.getAttributeMaxValues()[i] - database.getAttributeMinValues()[i]); } } /** * Returns the original instance * * @return originalInstance */ public Instance getInstance() { return instance; } /** * Returns the key for this DataObject * * @return key */ public String getKey() { return key; } /** * Sets the key for this DataObject * * @param key * The key is represented as string */ public void setKey(String key) { this.key = key; } /** * Sets the clusterID (cluster), to which this DataObject belongs to * * @param clusterID * Number of the Cluster */ public void setClusterLabel(int clusterID) { this.clusterID = clusterID; } /** * Returns the clusterID, to which this DataObject belongs to * * @return clusterID */ public int getClusterLabel() { return clusterID; } /** * Marks this dataObject as processed * * @param processed * True, if the DataObject has been already processed, false else */ public void setProcessed(boolean processed) { this.processed = processed; } /** * Gives information about the status of a dataObject * * @return True, if this dataObject has been processed, else false */ public boolean isProcessed() { return processed; } /** * Sets a new coreDistance for this dataObject * * @param c_dist * coreDistance */ public void setCoreDistance(double c_dist) { this.c_dist = c_dist; } /** * Returns the coreDistance for this dataObject * * @return coreDistance */ public double getCoreDistance() { return c_dist; } /** * Sets a new reachability-distance for this dataObject */ public void setReachabilityDistance(double r_dist) { this.r_dist = r_dist; } /** * Returns the reachabilityDistance for this dataObject */ public double getReachabilityDistance() { return r_dist; } public String toString() { return instance.toString(); } /** * Returns the revision string. * * @return the revision */ public String getRevision() { return RevisionUtils.extract("$Revision: 8108 $"); } }