--- a/artifacts/src/main/java/org/dive4elements/river/artifacts/model/minfo/SedimentDensity.java	Thu Sep 05 15:47:24 2013 +0200
+++ b/artifacts/src/main/java/org/dive4elements/river/artifacts/model/minfo/SedimentDensity.java	Thu Sep 05 17:15:04 2013 +0200
@@ -95,15 +95,12 @@
         List<SedimentDensityValue> values,
         double km
     ) {
-        boolean found = false;
         SedimentDensityValue prev = null;
         SedimentDensityValue next = null;
         for (SedimentDensityValue sdv: values) {
             logger.debug("year: " + sdv.getYear());
-            if (sdv.getKm() == km) {
-                prev = sdv;
-                found = true;
-                break;
+            if (Math.abs(sdv.getKm() - km) < 0.00001) {
+                return prev.getDensity();
             }
             if (sdv.getKm() > km) {
                 next = sdv;
@@ -111,27 +108,31 @@
             }
             prev = sdv;
         }
-        if (found) {
-            return prev.getDensity();
-        }
-        else {
-            return spline(prev, next, km);
-        }
+        return spline(prev, next, km);
     }
 
-    private double spline(
+    private static double spline(
         SedimentDensityValue prev,
         SedimentDensityValue next,
         double km
     ) {
+        if (prev == null && next == null) {
+            logger.warn("prev and next are null -> NaN");
+            return Double.NaN;
+        }
+
+        if (prev == null) return next.getDensity();
+        if (next == null) return prev.getDensity();
+
+        // XXX: This is no spline interpolation!
         double lower = prev.getKm();
         double upper = next.getKm();
         double upperDensity = next.getDensity();
         double lowerDensity = prev.getDensity();
 
-        double m =(upperDensity - lowerDensity)/(upper - lower);
+        double m = (upperDensity - lowerDensity)/(upper - lower);
         double b = lowerDensity - (m * lower);
-        return (m * km) + b;
+        return m * km + b;
     }