Mercurial > dive4elements > river
view flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/LogLinear.java @ 2696:1bc35de0b786
Improved the states for MINFO flow velocity calculation.
flys-artifacts/trunk@4406 c6561f87-3c4e-4783-a992-168aeb5c3f6f
author | Ingo Weinzierl <ingo.weinzierl@intevation.de> |
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date | Tue, 15 May 2012 07:15:36 +0000 |
parents | 0dd58ab7e118 |
children | 4dda67a893da |
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package de.intevation.flys.artifacts.math.fitting; public class LogLinear extends Function { public LogLinear() { super( "log-linear", "W(Q) = a*ln(m*Q + b)", new String [] { "a", "m", "b" }); } @Override public double value(double x, double [] parameters) { return parameters[0]*Math.log(parameters[1]*x + parameters[2]); } @Override public double [] gradient(double x, double [] parameters) { double l = parameters[1]*x + parameters[2]; return new double [] { Math.log(l), parameters[0]*x/l, parameters[0]/l }; } } // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :