Mercurial > dive4elements > river
comparison flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/StdDevOutlier.java @ 4794:a7d080347ac3
MINFO: Allow two methods for outlier test in SQ relation.
* Methods can be switched as option in conf.xml.
* Methods:
- Find outliers via multiples of the standard deviation.
- Grubbs (used in Fix-Analysis)
| author | Raimund Renkert <rrenkert@intevation.de> |
|---|---|
| date | Fri, 11 Jan 2013 13:57:38 +0100 |
| parents | |
| children | 8ee270a3ef25 |
comparison
equal
deleted
inserted
replaced
| 4793:c0d6391bec6f | 4794:a7d080347ac3 |
|---|---|
| 1 package de.intevation.flys.artifacts.math; | |
| 2 | |
| 3 import java.util.List; | |
| 4 | |
| 5 import org.apache.commons.math.MathException; | |
| 6 | |
| 7 import org.apache.commons.math.distribution.TDistributionImpl; | |
| 8 | |
| 9 import org.apache.commons.math.stat.descriptive.moment.Mean; | |
| 10 import org.apache.commons.math.stat.descriptive.moment.StandardDeviation; | |
| 11 | |
| 12 import org.apache.log4j.Logger; | |
| 13 | |
| 14 import de.intevation.flys.artifacts.model.sq.SQ; | |
| 15 | |
| 16 public class StdDevOutlier | |
| 17 { | |
| 18 public static final double EPSILON = 1e-5; | |
| 19 | |
| 20 public static final double DEFAULT_FACTOR = 3; | |
| 21 | |
| 22 private static Logger log = Logger.getLogger(StdDevOutlier.class); | |
| 23 | |
| 24 protected StdDevOutlier() { | |
| 25 } | |
| 26 | |
| 27 public static Integer findOutlier(List<Double> values) { | |
| 28 return findOutlier(values, DEFAULT_FACTOR, null); | |
| 29 } | |
| 30 | |
| 31 public static Integer findOutlier(List<Double> values, double factor, double[] stdDevResult) { | |
| 32 boolean debug = log.isDebugEnabled(); | |
| 33 | |
| 34 if (debug) { | |
| 35 log.debug("factor for std dev: " + factor); | |
| 36 } | |
| 37 | |
| 38 int N = values.size(); | |
| 39 | |
| 40 if (debug) { | |
| 41 log.debug("Values to check: " + N); | |
| 42 } | |
| 43 | |
| 44 if (values.size() < 3) { | |
| 45 return null; | |
| 46 } | |
| 47 | |
| 48 StandardDeviation stdDev = new StandardDeviation(); | |
| 49 | |
| 50 double maxValue = -Double.MAX_VALUE; | |
| 51 int maxIndex = -1; | |
| 52 int ndx = 0; | |
| 53 for (int i = values.size()-1; i >= 0; --i) { | |
| 54 double value = Math.abs(values.get(i)); | |
| 55 stdDev.increment(value); | |
| 56 if (value > maxValue) { | |
| 57 maxValue = value; | |
| 58 maxIndex = ndx; | |
| 59 } | |
| 60 ++ndx; | |
| 61 } | |
| 62 | |
| 63 double sd = stdDev.getResult(); | |
| 64 | |
| 65 double accepted = factor * sd; | |
| 66 | |
| 67 if (debug) { | |
| 68 log.debug("std dev: " + stdDev); | |
| 69 log.debug("accepted: " + accepted); | |
| 70 log.debug("max value: " + maxValue); | |
| 71 } | |
| 72 if (stdDevResult != null) { | |
| 73 stdDevResult[0] = sd; | |
| 74 } | |
| 75 return maxValue > accepted ? maxIndex : null; | |
| 76 } | |
| 77 } | |
| 78 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 : |