Mercurial > dive4elements > river
comparison flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Quad.java @ 3009:4dda67a893da
FixA: Added the derivatives of all fitting functions.
flys-artifacts/trunk@4565 c6561f87-3c4e-4783-a992-168aeb5c3f6f
| author | Sascha L. Teichmann <sascha.teichmann@intevation.de> |
|---|---|
| date | Thu, 31 May 2012 16:32:03 +0000 |
| parents | 0dd58ab7e118 |
| children | 585c0b49e696 |
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| 3008:9e0500d64524 | 3009:4dda67a893da |
|---|---|
| 1 package de.intevation.flys.artifacts.math.fitting; | 1 package de.intevation.flys.artifacts.math.fitting; |
| 2 | 2 |
| 3 public class Quad | 3 public class Quad |
| 4 extends Function | 4 extends Function |
| 5 { | 5 { |
| 6 public static final Derivative DERIVATIVE = | |
| 7 new Derivative("W'(Q) = 2*n*Q+m") { | |
| 8 | |
| 9 @Override | |
| 10 public de.intevation.flys.artifacts.math.Function | |
| 11 instantiate(double [] parameters) | |
| 12 { | |
| 13 final double n = parameters[0]; | |
| 14 final double m = parameters[1]; | |
| 15 | |
| 16 return new de.intevation.flys.artifacts.math.Function() { | |
| 17 @Override | |
| 18 public double value(double Q) { | |
| 19 return 2*n*Q+m; | |
| 20 } | |
| 21 }; | |
| 22 } | |
| 23 }; | |
| 24 | |
| 6 public Quad() { | 25 public Quad() { |
| 7 super( | 26 super( |
| 8 "quad", | 27 "quad", |
| 9 "W(Q) = n*Q^2 + m*Q + b", | 28 "W(Q) = n*Q^2 + m*Q + b", |
| 10 new String [] { "n", "m", "b" }); | 29 new String [] { "n", "m", "b" }); |
| 18 | 37 |
| 19 @Override | 38 @Override |
| 20 public double [] gradient(double x, double [] parameters) { | 39 public double [] gradient(double x, double [] parameters) { |
| 21 return new double [] { x*x, x, 1d }; | 40 return new double [] { x*x, x, 1d }; |
| 22 } | 41 } |
| 42 | |
| 43 @Override | |
| 44 public Derivative getDerivative() { | |
| 45 return DERIVATIVE; | |
| 46 } | |
| 23 } | 47 } |
| 24 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 : | 48 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 : |