--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/artifacts/src/main/java/org/dive4elements/river/artifacts/model/fixings/FixDerivateFacet.java	Thu Apr 25 15:23:37 2013 +0200
@@ -0,0 +1,119 @@
+package org.dive4elements.river.artifacts.model.fixings;
+
+import org.dive4elements.artifacts.Artifact;
+import org.dive4elements.artifacts.CallContext;
+
+import org.dive4elements.river.artifacts.FLYSArtifact;
+
+import org.dive4elements.river.artifacts.access.FixAnalysisAccess;
+
+import org.dive4elements.river.artifacts.math.fitting.Function;
+import org.dive4elements.river.artifacts.math.fitting.FunctionFactory;
+
+import org.dive4elements.river.artifacts.model.CalculationResult;
+import org.dive4elements.river.artifacts.model.FacetTypes;
+import org.dive4elements.river.artifacts.model.Parameters;
+
+import org.dive4elements.river.artifacts.states.DefaultState.ComputeType;
+
+import org.apache.log4j.Logger;
+
+
+/**
+ * Facet to show the W|Q values.
+ *
+ * @author <a href="mailto:raimund.renkert@intevation.de">Raimund Renkert</a>
+ */
+public class FixDerivateFacet
+extends      FixingsFacet
+implements   FacetTypes {
+
+    /** House logger. */
+    private static Logger logger = Logger.getLogger(FixDerivateFacet.class);
+
+
+    /** Trivial Constructor. */
+    public FixDerivateFacet() {
+    }
+
+
+    /**
+     * @param name
+     */
+    public FixDerivateFacet(String name, String description) {
+        super(0, name, description, ComputeType.ADVANCE, null, null);
+    }
+
+    public FixDerivateFacet(int index, String name, String description) {
+        super(index, name, description, ComputeType.ADVANCE, null, null);
+    }
+
+
+    /**
+     * Returns the data this facet requires.
+     *
+     * @param artifact the owner artifact.
+     * @param context  the CallContext (ignored).
+     *
+     * @return the data.
+     */
+    @Override
+    public Object getData(Artifact artifact, CallContext context) {
+
+        logger.debug("FixDerivateFacet.getData");
+        if (!(artifact instanceof FLYSArtifact)) {
+            logger.debug("Not an instance of FixationArtifact.");
+            return null;
+        }
+
+        FLYSArtifact flys = (FLYSArtifact)artifact;
+        FixAnalysisAccess access = new FixAnalysisAccess(flys, context);
+
+        CalculationResult res =
+            (CalculationResult) flys.compute(context,
+                                             ComputeType.ADVANCE,
+                                             false);
+
+        FixAnalysisResult result = (FixAnalysisResult) res.getData();
+        double currentKm = getCurrentKm(context);
+
+        String function = access.getFunction();
+        Function ff = FunctionFactory.getInstance().getFunction(function);
+        Function.Derivative fd = ff.getDerivative();
+
+        Parameters params = result.getParameters();
+        double maxQ = FixFacetUtils.getMaxQ(params, currentKm);
+
+        String[] paramNames = ff.getParameterNames();
+
+        double[] coeffs = params.interpolate("km", currentKm, paramNames);
+        if (coeffs == null) {
+            logger.warn("getData: coeffs == null");
+            return null;
+        }
+
+        org.dive4elements.river.artifacts.math.Function mf =
+            fd.instantiate(coeffs);
+
+        FixFunction fix = new FixFunction(
+            "",
+            fd.getDescription(),
+            mf,
+            maxQ);
+
+        return fix;
+    }
+
+
+    /**
+     * Create a deep copy of this Facet.
+     * @return a deep copy.
+     */
+    @Override
+    public FixDerivateFacet deepCopy() {
+        FixDerivateFacet copy = new FixDerivateFacet();
+        copy.set(this);
+        return copy;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :