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1
11 package org.eclipse.test.internal.performance.eval;
12
13 import java.util.HashMap  ;
14 import java.util.HashSet ;
15 import java.util.Map ;
16 import java.util.Set ;
17
18 import org.eclipse.test.internal.performance.InternalPerformanceMeter;
19 import org.eclipse.test.internal.performance.data.DataPoint;
20 import org.eclipse.test.internal.performance.data.Dim;
21 import org.eclipse.test.internal.performance.data.Scalar;
22
23 import junit.framework.Assert;
24
25
28 public class StatisticsSession {
29
30 static final class Statistics {
31 public long count;
32 public long sum;
33 public double average;
34 public double stddev;
35 }
36
37 private final DataPoint[] fDataPoints;
38 private final Map fStatistics= new HashMap ();
39
40 public StatisticsSession(DataPoint[] datapoints) {
41 fDataPoints= datapoints;
42 }
43
44 public double getAverage(Dim dimension) {
45 return getStats(dimension).average;
46 }
47
48 public long getSum(Dim dimension) {
49 return getStats(dimension).sum;
50 }
51
52 public long getCount(Dim dimension) {
53 return getStats(dimension).count;
54 }
55
56 public double getStddev(Dim dimension) {
57 return getStats(dimension).stddev;
58 }
59
60 private Statistics getStats(Dim dimension) {
61 Statistics stats= (Statistics) fStatistics.get(dimension);
62 if (stats == null) {
63 stats= computeStats(dimension);
64 fStatistics.put(dimension, stats);
65 }
66 return stats;
67 }
68
69 private Statistics computeStats(Dim dimension) {
70
71 Statistics stats= new Statistics();
72
73 Set set= new HashSet ();
74 for (int j= 0; j < fDataPoints.length; j++) {
75 DataPoint dp= fDataPoints[j];
76 set.add(new Integer (dp.getStep()));
77 }
78
79 long mags[]= new long[fDataPoints.length];
80 switch (set.size()) {
81 case 1:
82 for (int i= 0; i < fDataPoints.length; i++) {
84 Scalar sc= fDataPoints[i].getScalar(dimension);
85 if (sc != null) {
86 long magnitude= sc.getMagnitude();
87 mags[i]= magnitude;
88 stats.sum += magnitude;
89 stats.count++;
90 }
91 }
92 if (stats.count > 0) {
93 stats.average= stats.sum / stats.count;
94 for (int i= 0; i < fDataPoints.length; i++) {
95 stats.stddev+= (stats.average - mags[i]) * (stats.average - mags[i]);
96 }
97 }
98 break;
99 case 2:
100 for (int i= 0; i < fDataPoints.length-1; i += 2) {
101 DataPoint before= fDataPoints[i];
102 Assert.assertTrue("wrong order of steps", before.getStep() == InternalPerformanceMeter.BEFORE); DataPoint after= fDataPoints[i + 1];
104 Assert.assertTrue("wrong order of steps", after.getStep() == InternalPerformanceMeter.AFTER);
106 Scalar delta= getDelta(before, after, dimension);
107 long magnitude= delta.getMagnitude();
108 mags[i]= magnitude;
109 stats.sum += magnitude;
110 stats.count++;
111 }
112 if (stats.count > 0) {
113 stats.average= stats.sum / stats.count;
114 for (int i= 0; i < fDataPoints.length-1; i += 2) {
115 stats.stddev+= (stats.average - mags[i]) * (stats.average - mags[i]);
116 }
117 }
118 break;
119 default:
120 Assert.assertTrue("cannot handle more than two steps", false); break;
122 }
123
124 stats.stddev= Math.sqrt(stats.stddev / stats.count);
125
126 return stats;
127 }
128
129 private Scalar getDelta(DataPoint before, DataPoint after, Dim dimension) {
130 Scalar one= before.getScalar(dimension);
131 Assert.assertTrue("reference has no value for dimension " + dimension, one != null);
133 Scalar two= after.getScalar(dimension);
134 Assert.assertTrue("reference has no value for dimension " + dimension, two != null);
136 return new Scalar(one.getDimension(), two.getMagnitude() - one.getMagnitude());
137 }
138
139 public boolean contains(Dim dimension) {
140 if (fDataPoints.length > 0)
141 return fDataPoints[0].contains(dimension);
142 return false;
143 }
144 }
145 |
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