Mercurial > dive4elements > river
changeset 4631:d35d316049e8
A little optimization and handle the case that there are duplicates in the values.
author | Sascha L. Teichmann <teichmann@intevation.de> |
---|---|
date | Mon, 03 Dec 2012 21:16:15 +0100 |
parents | 63368dcc3f94 |
children | 02cf2b1dff84 |
files | flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/MovingAverage.java |
diffstat | 1 files changed, 19 insertions(+), 12 deletions(-) [+] |
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--- a/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/MovingAverage.java Mon Dec 03 18:44:48 2012 +0100 +++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/MovingAverage.java Mon Dec 03 21:16:15 2012 +0100 @@ -10,49 +10,56 @@ public static double[][] simple(double[][] values, double radius) { TreeMap<Double, Double> map = toMap(values); - double[][] result = new double[values.length][values[0].length]; + int N = map.size(); + double [] xs = new double[N]; + double [] ys = new double[N]; int ndx = 0; for (double x: map.keySet()) { SortedMap<Double, Double> range = map.subMap(x-radius, true, x+radius, true); double avg = 0d; - for (Double v: range.values()) { + for (double v: range.values()) { avg += v; } avg /= range.size(); - result[0][ndx] = x; - result[1][ndx] = avg; + xs[ndx] = x; + ys[ndx] = avg; ndx++; } - return result; + return new double [][] { xs, ys }; } public static double[][] weighted(double[][] values, double radius) { TreeMap<Double, Double> map = toMap(values); - double[][] result = new double[values.length][values[0].length]; + int N = map.size(); + double [] xs = new double[N]; + double [] ys = new double[N]; int ndx = 0; + double _1radius = 1d/radius; for (double x: map.keySet()) { double avg = 0d; double weights = 0d; for (Map.Entry<Double, Double> e: map.subMap(x-radius, false, x+radius, false).entrySet() ) { - double weight = 1d - Math.abs(x - e.getKey())/radius; + double weight = 1d - Math.abs(x - e.getKey())*_1radius; avg += weight*e.getValue(); weights += weight; } avg /= weights; - result[0][ndx] = x; - result[1][ndx] = avg; + xs[ndx] = x; + ys[ndx] = avg; ndx++; } - return result; + return new double [][] { xs, ys }; } private static TreeMap<Double, Double> toMap(double[][] values) { TreeMap<Double, Double> map = new TreeMap<Double, Double>(); - for(int i = 0; i < values[0].length; i++) { - map.put(values[0][i], values[1][i]); + double [] xs = values[0]; + double [] ys = values[1]; + for (int i = 0; i < xs.length; i++) { + map.put(xs[i], ys[i]); } return map; }