1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
package org.eclipse.jetty.util.statistic;
//========================================================================
//Copyright (c) 2006-2012 Mort Bay Consulting Pty. Ltd.
//------------------------------------------------------------------------
//All rights reserved. This program and the accompanying materials
//are made available under the terms of the Eclipse Public License v1.0
//and Apache License v2.0 which accompanies this distribution.
//The Eclipse Public License is available at
//http://www.eclipse.org/legal/epl-v10.html
//The Apache License v2.0 is available at
//http://www.opensource.org/licenses/apache2.0.php
//You may elect to redistribute this code under either of these licenses.
//========================================================================
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
import org.junit.Test;
/* ------------------------------------------------------------ */
public class SampleStatisticTest
{
private static long[][] data =
{
{100,100,100,100,100,100,100,100,100,100},
{100,100,100,100,100,100,100,100,100,100,90,110},
{100,100,100,100,100,100,100,100,90,110,95,105,97,103},
{100,100,100,100,100,100,100,100,100,100,100,100,100,100,100,100,100,100,90,110,95,105,97,103},
};
private static double[][] results =
{ /* {mean,stddev}*/
{100.0,0.0},
{100.0,Math.sqrt((10*10+10*10)/12.0)},
{100.0,Math.sqrt((10*10+10*10+5*5+5*5+3*3+3*3)/14.0)},
{100.0,Math.sqrt((10*10+10*10+5*5+5*5+3*3+3*3)/24.0)},
{100.0,Math.sqrt((10*10+10*10+5*5+5*5+3*3+3*3)/104.0)}
};
@Test
public void testData()
throws Exception
{
SampleStatistic stats = new SampleStatistic();
for (int d=0;d<data.length;d++)
{
stats.reset();
for (long x : data[d])
stats.set(x);
assertEquals("count"+d,data[d].length, (int)stats.getCount());
assertNearEnough("mean"+d,results[d][0], stats.getMean());
assertNearEnough("stddev"+d,results[d][1], stats.getStdDev());
}
}
private void assertNearEnough(String test,double expected, double actual)
{
double diff = Math.abs(expected-actual);
if (diff<0.1)
{
System.out.println("Near enough "+test+" diff="+diff);
return;
}
String failed = "Not near enough "+test+" expected="+expected+" actual="+actual+" diff="+diff;
System.err.println(failed);
assertTrue(failed,false);
}
}
|