/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2011, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jfreechart/index.html
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
* Other names may be trademarks of their respective owners.]
*
* --------------------
* StatisticsTests.java
* --------------------
* (C) Copyright 2004-2008, by Object Refinery Limited and Contributors.
*
* Original Author: David Gilbert (for Object Refinery Limited);
* Contributor(s): -;
*
* Changes
* -------
* 25-Mar-2004 : Version 1 (DG);
* 04-Oct-2004 : Eliminated NumberUtils usage (DG);
*
*/
package org.jfree.data.statistics.junit;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jfree.data.statistics.Statistics;
/**
* Tests for the {@link Statistics} class.
*/
public class StatisticsTests extends TestCase {
/**
* Returns the tests as a test suite.
*
* @return The test suite.
*/
public static Test suite() {
return new TestSuite(StatisticsTests.class);
}
/**
* Constructs a new set of tests.
*
* @param name the name of the tests.
*/
public StatisticsTests(String name) {
super(name);
}
/**
* Some checks for the calculateMean(Number[]) and
* calculateMean(Number[], boolean) methods.
*/
public void testCalculateMean_Array() {
// try null array
boolean pass = false;
try {
Statistics.calculateMean((Number[]) null);
}
catch (IllegalArgumentException e) {
pass = true;
}
assertTrue(pass);
pass = false;
try {
Statistics.calculateMean((Number[]) null, false);
}
catch (IllegalArgumentException e) {
pass = true;
}
assertTrue(pass);
// try an array containing no items
assertTrue(Double.isNaN(Statistics.calculateMean(new Number[0])));
assertTrue(Double.isNaN(Statistics.calculateMean(new Number[0],
false)));
// try an array containing a single Number
Number[] values = new Number[] {new Double(1.0)};
assertEquals(1.0, Statistics.calculateMean(values), EPSILON);
assertEquals(1.0, Statistics.calculateMean(values, true), EPSILON);
assertEquals(1.0, Statistics.calculateMean(values, false), EPSILON);
// try an array containing a single Number and a null
values = new Number[] {new Double(1.0), null};
assertTrue(Double.isNaN(Statistics.calculateMean(values)));
assertTrue(Double.isNaN(Statistics.calculateMean(values, true)));
assertEquals(1.0, Statistics.calculateMean(values, false), EPSILON);
// try an array containing a single Number and a NaN
values = new Number[] {new Double(1.0), new Double(Double.NaN)};
assertTrue(Double.isNaN(Statistics.calculateMean(values)));
assertTrue(Double.isNaN(Statistics.calculateMean(values, true)));
assertEquals(1.0, Statistics.calculateMean(values, false), EPSILON);
}
/**
* Some checks for the calculateMean(Collection) and
* calculateMean(Collection, boolean) methods.
*/
public void testCalculateMean_Collection() {
// try a null collection
boolean pass = false;
try {
Statistics.calculateMean((Collection) null);
}
catch (IllegalArgumentException e) {
pass = true;
}
assertTrue(pass);
pass = false;
try {
Statistics.calculateMean((Collection) null, false);
}
catch (IllegalArgumentException e) {
pass = true;
}
assertTrue(pass);
// try an empty collection
List values = new ArrayList();
assertTrue(Double.isNaN(Statistics.calculateMean(values)));
assertTrue(Double.isNaN(Statistics.calculateMean(values, true)));
assertTrue(Double.isNaN(Statistics.calculateMean(values, false)));
// try a collection with a single number
values.add(new Double(9.0));
assertEquals(9.0, Statistics.calculateMean(values), EPSILON);
assertEquals(9.0, Statistics.calculateMean(values, true), EPSILON);
assertEquals(9.0, Statistics.calculateMean(values, false), EPSILON);
// try a collection with a single number plus a null
values.add(null);
assertTrue(Double.isNaN(Statistics.calculateMean(values)));
assertTrue(Double.isNaN(Statistics.calculateMean(values, true)));
assertEquals(9.0, Statistics.calculateMean(values, false), EPSILON);
// try a collection with a single number plus a NaN
values.clear();
values.add(new Double(9.0));
values.add(new Double(Double.NaN));
assertTrue(Double.isNaN(Statistics.calculateMean(values)));
assertTrue(Double.isNaN(Statistics.calculateMean(values, true)));
assertEquals(9.0, Statistics.calculateMean(values, false), EPSILON);
// try a collection with several numbers
values = new ArrayList();
values.add(new Double(9.0));
values.add(new Double(3.0));
values.add(new Double(2.0));
values.add(new Double(2.0));
double mean = Statistics.calculateMean(values);
assertEquals(4.0, mean, EPSILON);
// a Collection containing a NaN will return Double.NaN for the result
values.add(new Double(Double.NaN));
assertTrue(Double.isNaN(Statistics.calculateMean(values)));
}
static final double EPSILON = 0.0000000001;
/**
* Some checks for the calculateMedian(List, boolean) method.
*/
public void testCalculateMedian() {
// check null list
assertTrue(Double.isNaN(Statistics.calculateMedian(null, false)));
assertTrue(Double.isNaN(Statistics.calculateMedian(null, true)));
// check empty list
List list = new ArrayList();
assertTrue(Double.isNaN(Statistics.calculateMedian(list, false)));
assertTrue(Double.isNaN(Statistics.calculateMedian(list, true)));
// check list containing null
list.add(null);
boolean pass = false;
try {
Statistics.calculateMedian(list, false);
}
catch (NullPointerException e) {
pass = true;
}
assertTrue(pass);
pass = false;
try {
Statistics.calculateMedian(list, true);
}
catch (NullPointerException e) {
pass = true;
}
assertTrue(pass);
// check a list containing a non-Number object
list.clear();
list.add("Not a number");
pass = false;
try {
Statistics.calculateMedian(list, false);
}
catch (ClassCastException e) {
pass = true;
}
assertTrue(pass);
pass = false;
try {
Statistics.calculateMedian(list, true);
}
catch (ClassCastException e) {
pass = true;
}
assertTrue(pass);
}
/**
* A test for the calculateMedian() method.
*/
public void testCalculateMedian1() {
List values = new ArrayList();
values.add(new Double(1.0));
double median = Statistics.calculateMedian(values);
assertEquals(1.0, median, 0.0000001);
}
/**
* A test for the calculateMedian() method.
*/
public void testCalculateMedian2() {
List values = new ArrayList();
values.add(new Double(2.0));
values.add(new Double(1.0));
double median = Statistics.calculateMedian(values);
assertEquals(1.5, median, 0.0000001);
}
/**
* A test for the calculateMedian() method.
*/
public void testCalculateMedian3() {
List values = new ArrayList();
values.add(new Double(1.0));
values.add(new Double(2.0));
values.add(new Double(3.0));
values.add(new Double(6.0));
values.add(new Double(5.0));
values.add(new Double(4.0));
double median = Statistics.calculateMedian(values);
assertEquals(3.5, median, 0.0000001);
}
/**
* A test for the calculateMedian() method.
*/
public void testCalculateMedian4() {
List values = new ArrayList();
values.add(new Double(7.0));
values.add(new Double(2.0));
values.add(new Double(3.0));
values.add(new Double(5.0));
values.add(new Double(4.0));
values.add(new Double(6.0));
values.add(new Double(1.0));
double median = Statistics.calculateMedian(values);
assertEquals(4.0, median, 0.0000001);
}
/**
* A test using some real data that caused a problem at one point.
*/
public void testCalculateMedian5() {
List values = new ArrayList();
values.add(new Double(11.228692993861783));
values.add(new Double(11.30823353859889));
values.add(new Double(11.75312904769314));
values.add(new Double(11.825102897465314));
values.add(new Double(10.184252778401783));
values.add(new Double(12.207951828057766));
values.add(new Double(10.68841994040566));
values.add(new Double(12.099522004479438));
values.add(new Double(11.508874945056881));
values.add(new Double(12.052517729558513));
values.add(new Double(12.401481645578734));
values.add(new Double(12.185377793028543));
values.add(new Double(10.666372951930315));
values.add(new Double(11.680978041499548));
values.add(new Double(11.06528277406718));
values.add(new Double(11.36876492904596));
values.add(new Double(11.927565516175939));
values.add(new Double(11.39307785978655));
values.add(new Double(11.989603679523857));
values.add(new Double(12.009834360354864));
values.add(new Double(10.653351822461559));
values.add(new Double(11.851776254376754));
values.add(new Double(11.045441544755946));
values.add(new Double(11.993674040560624));
values.add(new Double(12.898219965238944));
values.add(new Double(11.97095782819647));
values.add(new Double(11.73234406745488));
values.add(new Double(11.649006017243991));
values.add(new Double(12.20549704915365));
values.add(new Double(11.799723639384919));
values.add(new Double(11.896208658005628));
values.add(new Double(12.164149111823424));
values.add(new Double(12.042795103513766));
values.add(new Double(12.114839532596426));
values.add(new Double(12.166609097075824));
values.add(new Double(12.183017546225935));
values.add(new Double(11.622009125845342));
values.add(new Double(11.289365786738633));
values.add(new Double(12.462984323671568));
values.add(new Double(11.573494921030598));
values.add(new Double(10.862867940485804));
values.add(new Double(12.018186939664872));
values.add(new Double(10.418046849313018));
values.add(new Double(11.326344465881341));
double median = Statistics.calculateMedian(values, true);
assertEquals(11.812413268425116, median, 0.000001);
Collections.sort(values);
double median2 = Statistics.calculateMedian(values, false);
assertEquals(11.812413268425116, median2, 0.000001);
}
/**
* A test for the calculateMedian() method.
*/
public void testCalculateMedian6() {
List values = new ArrayList();
values.add(new Double(7.0));
values.add(new Double(2.0));
values.add(new Double(3.0));
values.add(new Double(5.0));
values.add(new Double(4.0));
values.add(new Double(6.0));
values.add(new Double(1.0));
double median = Statistics.calculateMedian(values, 0, 2);
assertEquals(3.0, median, 0.0000001);
}
/**
* A simple test for the correlation calculation.
*/
public void testCorrelation1() {
Number[] data1 = new Number[3];
data1[0] = new Double(1);
data1[1] = new Double(2);
data1[2] = new Double(3);
Number[] data2 = new Number[3];
data2[0] = new Double(1);
data2[1] = new Double(2);
data2[2] = new Double(3);
double r = Statistics.getCorrelation(data1, data2);
assertEquals(1.0, r, 0.00000001);
}
/**
* A simple test for the correlation calculation.
*
* http://trochim.human.cornell.edu/kb/statcorr.htm
*/
public void testCorrelation2() {
Number[] data1 = new Number[20];
data1[0] = new Double(68);
data1[1] = new Double(71);
data1[2] = new Double(62);
data1[3] = new Double(75);
data1[4] = new Double(58);
data1[5] = new Double(60);
data1[6] = new Double(67);
data1[7] = new Double(68);
data1[8] = new Double(71);
data1[9] = new Double(69);
data1[10] = new Double(68);
data1[11] = new Double(67);
data1[12] = new Double(63);
data1[13] = new Double(62);
data1[14] = new Double(60);
data1[15] = new Double(63);
data1[16] = new Double(65);
data1[17] = new Double(67);
data1[18] = new Double(63);
data1[19] = new Double(61);
Number[] data2 = new Number[20];
data2[0] = new Double(4.1);
data2[1] = new Double(4.6);
data2[2] = new Double(3.8);
data2[3] = new Double(4.4);
data2[4] = new Double(3.2);
data2[5] = new Double(3.1);
data2[6] = new Double(3.8);
data2[7] = new Double(4.1);
data2[8] = new Double(4.3);
data2[9] = new Double(3.7);
data2[10] = new Double(3.5);
data2[11] = new Double(3.2);
data2[12] = new Double(3.7);
data2[13] = new Double(3.3);
data2[14] = new Double(3.4);
data2[15] = new Double(4.0);
data2[16] = new Double(4.1);
data2[17] = new Double(3.8);
data2[18] = new Double(3.4);
data2[19] = new Double(3.6);
double r = Statistics.getCorrelation(data1, data2);
assertEquals(0.7306356862792885, r, 0.000000000001);
}
/**
* Some checks for the getStdDev() method.
*/
public void testGetStdDev() {
// try null argument
boolean pass = false;
try {
Statistics.getStdDev(null);
}
catch (IllegalArgumentException e) {
pass = true;
}
assertTrue(pass);
// try zero length array
pass = false;
try {
Statistics.getStdDev(new Double[0]);
}
catch (IllegalArgumentException e) {
pass = true;
}
assertTrue(pass);
// try single value
assertTrue(Double.isNaN(Statistics.getStdDev(new Double[]
{new Double(1.0)})));
}
}