--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/org/dive4elements/river/artifacts/model/sq/Fitting.java	Thu Apr 25 12:06:39 2013 +0200
@@ -0,0 +1,149 @@
+package org.dive4elements.river.artifacts.model.sq;
+
+import org.dive4elements.river.artifacts.math.fitting.Function;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.commons.math.MathException;
+
+import org.apache.commons.math.optimization.fitting.CurveFitter;
+
+import org.apache.commons.math.optimization.general.LevenbergMarquardtOptimizer;
+
+import org.apache.log4j.Logger;
+
+public class Fitting
+implements   Outlier.Callback
+{
+    private static Logger log = Logger.getLogger(Fitting.class);
+
+    public interface Callback {
+
+        void afterIteration(
+            double [] parameters,
+            SQ []     measurements,
+            SQ []     outliers,
+            double    standardDeviation,
+            double    chiSqr);
+    } // interfacte
+
+    protected Function function;
+
+    protected double [] coeffs;
+
+    protected org.dive4elements.river.artifacts.math.Function instance;
+
+    protected double stdDevFactor;
+    protected double chiSqr;
+
+    protected Callback callback;
+
+    public Fitting() {
+    }
+
+    public Fitting(Function function, double stdDevFactor) {
+        this();
+        this.function     = function;
+        this.stdDevFactor = stdDevFactor;
+    }
+
+    public Function getFunction() {
+        return function;
+    }
+
+    public void setFunction(Function function) {
+        this.function = function;
+    }
+
+    public double getStdDevFactor() {
+        return stdDevFactor;
+    }
+
+    public void setStdDevFactor(double stdDevFactor) {
+        this.stdDevFactor = stdDevFactor;
+    }
+
+    @Override
+    public void initialize(List<SQ> sqs) throws MathException {
+
+        LevenbergMarquardtOptimizer lmo =
+            new LevenbergMarquardtOptimizer();
+
+        CurveFitter cf = new CurveFitter(lmo);
+        for (SQ sq: sqs) {
+            cf.addObservedPoint(sq.getQ(), sq.getS());
+        }
+
+        coeffs = cf.fit(
+            function, function.getInitialGuess());
+
+        instance = function.instantiate(coeffs);
+
+        chiSqr = lmo.getChiSquare();
+    }
+
+    @Override
+    public double eval(SQ sq) {
+        double s = instance.value(sq.q);
+        return sq.s - s;
+    }
+
+    @Override
+    public void iterationFinished(
+        double   standardDeviation,
+        SQ       outlier,
+        List<SQ> remainings
+    ) {
+        if (log.isDebugEnabled()) {
+            log.debug("iterationFinished ----");
+            log.debug(" num remainings: " + remainings.size());
+            log.debug(" has outlier: " + outlier != null);
+            log.debug(" standardDeviation: " + standardDeviation);
+            log.debug(" Chi^2: " + chiSqr);
+            log.debug("---- iterationFinished");
+        }
+        callback.afterIteration(
+            coeffs,
+            remainings.toArray(new SQ[remainings.size()]),
+            outlier != null ? new SQ [] { outlier} : new SQ [] {},
+            standardDeviation,
+            chiSqr);
+    }
+
+    protected static final List<SQ> onlyValid(List<SQ> sqs) {
+
+        List<SQ> good = new ArrayList<SQ>(sqs.size());
+
+        for (SQ sq: sqs) {
+            if (sq.isValid()) {
+                good.add(sq);
+            }
+        }
+
+        return good;
+    }
+
+    public boolean fit(List<SQ> sqs, String method, Callback callback) {
+
+        sqs = onlyValid(sqs);
+
+        if (sqs.size() < 2) {
+            log.warn("Too less points for fitting.");
+            return false;
+        }
+
+        this.callback = callback;
+
+        try {
+            Outlier.detectOutliers(this, sqs, stdDevFactor, method);
+        }
+        catch (MathException me) {
+            log.warn(me);
+            return false;
+        }
+
+        return true;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :