--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/artifacts/src/main/java/org/dive4elements/river/artifacts/sinfo/flowdepth/FlowVelocityKmModelValues.java	Thu Feb 22 12:03:31 2018 +0100
@@ -0,0 +1,186 @@
+/* Copyright (C) 2017 by Bundesanstalt für Gewässerkunde
+ * Software engineering by
+ *  Björnsen Beratende Ingenieure GmbH
+ *  Dr. Schumacher Ingenieurbüro für Wasser und Umwelt
+ *
+ * This file is Free Software under the GNU AGPL (>=v3)
+ * and comes with ABSOLUTELY NO WARRANTY! Check out the
+ * documentation coming with Dive4Elements River for details.
+ */
+
+package org.dive4elements.river.artifacts.sinfo.flowdepth;
+
+import org.apache.commons.math.analysis.interpolation.LinearInterpolator;
+import org.apache.commons.math.analysis.polynomials.PolynomialSplineFunction;
+
+import gnu.trove.TDoubleArrayList;
+
+/**
+ * Sorted arrays of a station's q, v, and tau model values, running in parallel
+ * @author Matthias Schäfer
+ *
+ */
+public class FlowVelocityKmModelValues {
+
+    /***** FIELDS *****/
+    
+    /**
+     * Km
+     */
+    private double km;
+    
+    /**
+     * The station's discharge model values, sorted in ascending order
+     */
+    private TDoubleArrayList qs;
+    
+    /**
+     * The station's main section velocity for the q values
+     */
+    private TDoubleArrayList vmains;
+    
+    /**
+     * The station's shear stress (tau) values for the q values
+     */
+    private TDoubleArrayList taus;
+
+    /**
+     * Discharge found by the last findQ
+     */
+    private double findQ;
+    
+    /**
+     * Velocity found by the last {@link findQ}
+     */
+    private double vmainFound;
+    
+    /**
+     * Shear stress found by the last {@link findQ}
+     */
+    private double tauFound;
+    
+    /**
+     * Whether qFound has been interpolated
+     */
+    private boolean isInterpolated;
+    
+    /**
+     * Real linear interpolator for q and v values
+     */
+    private PolynomialSplineFunction vInterpolator;
+    
+    /**
+     * Real linear interpolator for q and tau values
+     */
+    private PolynomialSplineFunction tauInterpolator;
+    
+    
+    /***** CONSTRUCTORS *****/
+    
+    /**
+     * Constructor with km parameter
+     */
+    public FlowVelocityKmModelValues(double km) {
+        this.km = km;
+        qs = new TDoubleArrayList();
+        vmains = new TDoubleArrayList();
+        taus = new TDoubleArrayList();
+        vInterpolator = null;
+        tauInterpolator = null;
+    }
+
+    /**
+     * Copy constructor with new km
+     */
+    public FlowVelocityKmModelValues(double km, FlowVelocityKmModelValues src) {
+        this(km);
+        src.copyTo(qs, vmains, taus);
+    }
+    
+    /***** METHODS *****/
+    
+    /**
+     * Number of the q-v-tau tuples
+     */
+    public int size() {
+        if (qs != null)
+            return qs.size();
+        else
+            return 0;
+    }
+    
+    /**
+     * Km
+     */
+    public double getKm() {
+        return km;
+    }
+    
+    /**
+     * Adds all q-v-tau to another set of arrays
+     */
+    void copyTo(TDoubleArrayList dstqs, TDoubleArrayList dstvmains, TDoubleArrayList dsttaus) {
+        for (int i = 0; i <= qs.size(); i++) {
+            dstqs.add(qs.getQuick(i));
+            dstvmains.add(vmains.getQuick(i));
+            dsttaus.add(taus.getQuick(i));
+        }
+    }
+    
+    /**
+     * Discharge found by the last {@link findQ}
+     * @return
+     */
+    public double getFindQ() {
+        return findQ;
+    }
+    
+    /**
+     * Velocity found by the last {@link findQ}
+     */
+    public double getVmainFound() {
+        return vmainFound;
+    }
+    
+    /**
+     * Shear stress found by the last {@link findQ}
+     */
+    public double getTauFound() {
+        return tauFound;
+    }
+    
+    /**
+     * Whether qFound has been interpolated 
+     */
+    public boolean getIsInterpolated() {
+        return isInterpolated;
+    }
+    
+    /**
+     * Adds a q-v-tau value triple. 
+     */
+    public void addValues(double q, double vmain, double tau) {
+        qs.add(q);
+        vmains.add(vmain);
+        taus.add(tau);
+    }
+    
+    /**
+     * Searches a discharge value and returns it or the interpolated value
+     * @return Found or interpolated discharge, or NaN otherwise
+     */
+    public double findQ(double q) {
+        if (vInterpolator == null) {
+            vInterpolator = new LinearInterpolator().interpolate(qs.toNativeArray(), vmains.toNativeArray());
+            tauInterpolator = new LinearInterpolator().interpolate(qs.toNativeArray(), taus.toNativeArray());
+        }
+        findQ = q;
+        try {
+            vmainFound = vInterpolator.value(q);
+            tauFound = tauInterpolator.value(q);
+        } catch (Exception e) {
+            q = Double.NaN;
+        }
+        return q;
+    }
+}