Source for org.jfree.data.statistics.MeanAndStandardDeviation

   1: /* ===========================================================
   2:  * JFreeChart : a free chart library for the Java(tm) platform
   3:  * ===========================================================
   4:  *
   5:  * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
   6:  *
   7:  * Project Info:  http://www.jfree.org/jfreechart/index.html
   8:  *
   9:  * This library is free software; you can redistribute it and/or modify it 
  10:  * under the terms of the GNU Lesser General Public License as published by 
  11:  * the Free Software Foundation; either version 2.1 of the License, or 
  12:  * (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but 
  15:  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
  16:  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
  17:  * License for more details.
  18:  *
  19:  * You should have received a copy of the GNU Lesser General Public
  20:  * License along with this library; if not, write to the Free Software
  21:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
  22:  * USA.  
  23:  *
  24:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
  25:  * in the United States and other countries.]
  26:  *
  27:  * -----------------------------
  28:  * MeanAndStandardDeviation.java
  29:  * -----------------------------
  30:  * (C) Copyright 2003-2005, by Object Refinery Limited.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * $Id: MeanAndStandardDeviation.java,v 1.3.2.1 2005/10/25 21:34:46 mungady Exp $
  36:  *
  37:  * Changes:
  38:  * --------
  39:  * 05-Feb-2002 : Version 1 (DG);
  40:  * 05-Feb-2005 : Added equals() method and implemented Serializable (DG);
  41:  *
  42:  */
  43: 
  44: package org.jfree.data.statistics;
  45: 
  46: import java.io.Serializable;
  47: 
  48: import org.jfree.util.ObjectUtilities;
  49: 
  50: /**
  51:  * A simple data structure that holds a mean value and a standard deviation 
  52:  * value.  This is used in the 
  53:  * {@link org.jfree.data.statistics.DefaultStatisticalCategoryDataset} class.
  54:  */
  55: public class MeanAndStandardDeviation implements Serializable {
  56: 
  57:     /** For serialization. */
  58:     private static final long serialVersionUID = 7413468697315721515L;
  59:     
  60:     /** The mean. */
  61:     private Number mean;
  62: 
  63:     /** The standard deviation. */
  64:     private Number standardDeviation;
  65: 
  66:     /**
  67:      * Creates a new mean and standard deviation record.
  68:      * 
  69:      * @param mean  the mean.
  70:      * @param standardDeviation  the standard deviation.
  71:      */
  72:     public MeanAndStandardDeviation(double mean, double standardDeviation) {
  73:         this(new Double(mean), new Double(standardDeviation));   
  74:     }
  75:     
  76:     /**
  77:      * Creates a new mean and standard deviation record.
  78:      *
  79:      * @param mean  the mean (<code>null</code> permitted).
  80:      * @param standardDeviation  the standard deviation (<code>null</code>
  81:      *                           permitted.
  82:      */
  83:     public MeanAndStandardDeviation(Number mean, Number standardDeviation) {
  84:         this.mean = mean;
  85:         this.standardDeviation = standardDeviation;
  86:     }
  87: 
  88:     /**
  89:      * Returns the mean.
  90:      *
  91:      * @return The mean.
  92:      */
  93:     public Number getMean() {
  94:         return this.mean;
  95:     }
  96: 
  97:     /**
  98:      * Returns the standard deviation.
  99:      *
 100:      * @return The standard deviation.
 101:      */
 102:     public Number getStandardDeviation() {
 103:         return this.standardDeviation;
 104:     }
 105: 
 106:     /**
 107:      * Tests this instance for equality with an arbitrary object.
 108:      * 
 109:      * @param obj  the object (<code>null</code> permitted).
 110:      * 
 111:      * @return A boolean.
 112:      */
 113:     public boolean equals(Object obj) {
 114:         if (obj == this) {
 115:             return true;   
 116:         }
 117:         if (!(obj instanceof MeanAndStandardDeviation)) {
 118:             return false;   
 119:         }
 120:         MeanAndStandardDeviation that = (MeanAndStandardDeviation) obj;
 121:         if (!ObjectUtilities.equal(this.mean, that.mean)) {
 122:             return false;   
 123:         }
 124:         if (!ObjectUtilities.equal(
 125:             this.standardDeviation, that.standardDeviation)
 126:         ) {
 127:             return false;   
 128:         }
 129:         return true;
 130:     }
 131: }