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comparison artifacts/src/main/java/org/dive4elements/river/artifacts/math/fitting/InvSQPow.java @ 9643:58f3fe98fd6b

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Fitting new Option UI
author dnt_bjoernsen <d.tironi@bjoernsen.de>
date Mon, 02 Dec 2019 14:14:06 +0100
parents af13ceeba52a
children
comparison
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9642:3987fef69143 9643:58f3fe98fd6b
6 * documentation coming with Dive4Elements River for details. 6 * documentation coming with Dive4Elements River for details.
7 */ 7 */
8 8
9 package org.dive4elements.river.artifacts.math.fitting; 9 package org.dive4elements.river.artifacts.math.fitting;
10 10
11 public class InvSQPow 11 public class InvSQPow extends Function {
12 extends Function 12 public static final Derivative DERIVATIVE = new Derivative("Q'(S) = (S/a)^(1/b)/(b*S)") {
13 {
14 public static final Derivative DERIVATIVE =
15 new Derivative("Q'(S) = (S/a)^(1/b)/(b*S)") {
16 13
17 @Override 14 @Override
18 public org.dive4elements.river.artifacts.math.Function 15 public org.dive4elements.river.artifacts.math.Function instantiate(final double[] parameters) {
19 instantiate(double [] parameters) 16 final double _1a = 1d / parameters[0];
20 { 17 final double b = parameters[1];
21 final double _1a = 1d/parameters[0]; 18 final double _1b = 1d / b;
22 final double b = parameters[1];
23 final double _1b = 1d/b;
24 19
25 return new org.dive4elements.river.artifacts.math.Function() { 20 return new org.dive4elements.river.artifacts.math.Function() {
26 @Override 21 @Override
27 public double value(double S) { 22 public double value(final double S) {
28 return Math.pow(S*_1a, _1b)/(b*S); 23 return Math.pow(S * _1a, _1b) / (b * S);
29 } 24 }
30 }; 25 };
31 } 26 }
32 }; 27 };
33 public static final Function INSTANCE = new InvSQPow(); 28 public static final Function INSTANCE = new InvSQPow();
34 29
35 public InvSQPow() { 30 public InvSQPow() {
36 super( 31 super("inv-special", "Q(S) = Q=(S/a)^(1/b)", new String[] { "a", "b" });
37 "inv-sq-pow",
38 "Q(S) = Q=(S/a)^(1/b)",
39 new String [] { "a", "b" });
40 } 32 }
41 33
42 @Override 34 @Override
43 public double value(double S, double [] parameters) { 35 public double value(final double S, final double[] parameters) {
44 double a = parameters[0]; 36 final double a = parameters[0];
45 double b = parameters[1]; 37 final double b = parameters[1];
46 return Math.pow(S/a, 1d/b); 38 return Math.pow(S / a, 1d / b);
47 } 39 }
48 40
49 @Override 41 @Override
50 public double [] gradient(double S, double [] parameters) { 42 public double[] gradient(final double S, final double[] parameters) {
51 double a = parameters[0]; 43 final double a = parameters[0];
52 double b = parameters[1]; 44 final double b = parameters[1];
53 double Sa = S/a; 45 final double Sa = S / a;
54 double _1b = 1d/b; 46 final double _1b = 1d / b;
55 double eSa1b = Math.pow(Sa, _1b); 47 final double eSa1b = Math.pow(Sa, _1b);
56 return new double [] { 48 return new double[] { -eSa1b / (a * b), -(eSa1b * Math.log(Sa)) / (b * b) };
57 -eSa1b/(a*b),
58 -(eSa1b*Math.log(Sa))/(b*b)
59 };
60 } 49 }
61 50
62 @Override 51 @Override
63 public Derivative getDerivative() { 52 public Derivative getDerivative() {
64 return DERIVATIVE; 53 return DERIVATIVE;
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