Mercurial > dive4elements > river

annotate flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/Linear.java @ 4128:11c589d68f13

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Fix for NPE in FLYSWorkspace.bringUp() #933
author Christian Lins <christian.lins@intevation.de>
date Sun, 14 Oct 2012 10:15:50 +0200
parents da1969b05292
children
rev   line source
655
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
1 package de.intevation.flys.artifacts.math;
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
2
742
c09c9e05ecfa Removed trailing whitespace.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 655
diff changeset
3 public final class Linear
655
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
4 implements Function
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
5 {
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
6 private double m;
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
7 private double b;
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
8
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
9 public Linear(
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
10 double x1, double x2,
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
11 double y1, double y2
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
12 ) {
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
13 // y1 = m*x1 + b
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
14 // y2 = m*x2 + b
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
15 // y2 - y1 = m*(x2 - x1)
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
16 // m = (y2 - y1)/(x2 - x1) # x2 != x1
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
17 // b = y1 - m*x1
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
18
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
19 if (x1 == x2) {
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
20 m = 0;
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
21 b = 0.5*(y1 + y2);
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
22 }
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
23 else {
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
24 m = (y2 - y1)/(x2 - x1);
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
25 b = y1 - m*x1;
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
26 }
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
27 }
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
28
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
29 public static final double linear(
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
30 double x,
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
31 double x1, double x2,
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
32 double y1, double y2
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
33 ) {
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
34 // y1 = m*x1 + b
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
35 // y2 = m*x2 + b
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
36 // y2 - y1 = m*(x2 - x1)
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
37 // m = (y2 - y1)/(x2 - x1) # x2 != x1
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
38 // b = y1 - m*x1
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
39
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
40 if (x1 == x2) {
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
41 return 0.5*(y1 + y2);
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
42 }
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
43 double m = (y2 - y1)/(x2 - x1);
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
44 double b = y1 - m*x1;
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
45 return x*m + b;
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
46 }
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
47
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
48 @Override
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
49 public double value(double x) {
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
50 return m*x + b;
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
51 }
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
52
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
53 public static final double factor(double x, double p1, double p2) {
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
54 // 0 = m*p1 + b <=> b = -m*p1
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
55 // 1 = m*p2 + b
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
56 // 1 = m*(p2 - p1)
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
57 // m = 1/(p2 - p1) # p1 != p2
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
58 // f(x) = x/(p2-p1) - p1/(p2-p1) <=> (x-p1)/(p2-p1)
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
59
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
60 return p1 == p2 ? 0.0 : (x-p1)/(p2-p1);
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
61 }
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
62
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
63 public static final double weight(double factor, double a, double b) {
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
64 //return (1.0-factor)*a + factor*b;
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
65 return a + factor*(b-a);
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
66 }
3736
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
67
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
68 public static final void weight(
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
69 double factor,
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
70 double [] a, double [] b, double [] c
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
71 ) {
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
72 int N = Math.min(Math.min(a.length, b.length), c.length);
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
73 for (int i = 0; i < N; ++i) {
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
74 c[i] = weight(factor, a[i], b[i]);
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
75 }
da1969b05292 WST tables: Added interpolation of tabulated values only.
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents: 742
diff changeset
76 }
655
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
77 }
913b52064449 Refactored version of "Berechnung 4"
Sascha L. Teichmann <sascha.teichmann@intevation.de>
parents:
diff changeset
78 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
http://dive4elements.wald.intevation.org