Mercurial > dive4elements > river
view flys-artifacts/src/main/java/de/intevation/flys/artifacts/model/extreme/Curve.java @ 4241:49cb65d5932d
Improved the historical discharge calculation.
The calculation now creates new HistoricalWQKms (new subclass of WQKms). Those WQKms are used
to create new facets from (new) type 'HistoricalDischargeCurveFacet'. The chart generator is
improved to support those facets.
author | Ingo Weinzierl <ingo.weinzierl@intevation.de> |
---|---|
date | Wed, 24 Oct 2012 14:34:35 +0200 |
parents | 467efea19d15 |
children | 5cc9453456a7 |
line wrap: on
line source
package de.intevation.flys.artifacts.model.extreme; import de.intevation.flys.artifacts.math.Function; import de.intevation.flys.artifacts.math.NaNFunction; import de.intevation.flys.artifacts.math.UnivariateRealFunctionFunction; import de.intevation.flys.artifacts.math.fitting.FunctionFactory; import java.io.Serializable; import java.lang.ref.SoftReference; import org.apache.commons.math.analysis.interpolation.SplineInterpolator; import org.apache.commons.math.exception.MathIllegalArgumentException; import org.apache.log4j.Logger; public class Curve implements Serializable, Function { private static Logger log = Logger.getLogger(Curve.class); protected double [] qs; protected double [] ws; protected String function; protected double [] coeffs; // The spline is pretty heavy weight so cache it with a soft ref only. protected transient SoftReference<Function> spline; protected transient Function extrapolation; public Curve() { } public Curve( double [] qs, double [] ws, String function, double [] coeffs ) { this.qs = qs; this.ws = ws; this.function = function; this.coeffs = coeffs; } public double [] getQs() { return qs; } public double [] getWs() { return ws; } public String getFunction() { return function; } public double [] getCoeffs() { return coeffs; } @Override public double value(double x) { if (x < qs[0]) return Double.NaN; return (x <= qs[qs.length-1] ? getSpline() : getExtrapolation()).value(x); } protected synchronized Function getExtrapolation() { if (extrapolation == null) { de.intevation.flys.artifacts.math.fitting.Function f = FunctionFactory.getInstance().getFunction(function); extrapolation = f != null ? f.instantiate(coeffs) : NaNFunction.INSTANCE; } return extrapolation; } protected synchronized Function getSpline() { Function sp; if (spline != null) { if ((sp = spline.get()) != null) { return sp; } } spline = new SoftReference<Function>(sp = createSpline()); return sp; } protected Function createSpline() { SplineInterpolator interpolator = new SplineInterpolator(); try { return new UnivariateRealFunctionFunction( interpolator.interpolate(qs, ws)); } catch (MathIllegalArgumentException miae) { log.debug("creation on spline failed", miae); return NaNFunction.INSTANCE; } } } // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf-8 :