--- a/gnv-artifacts/ChangeLog	Wed Dec 23 12:20:25 2009 +0000
+++ b/gnv-artifacts/ChangeLog	Wed Dec 23 15:28:40 2009 +0000
@@ -1,3 +1,29 @@
+2009-12-23	Sascha L. Teichmann	<sascha.teichmann@intevation.de>
+
+	* src/main/java/de/intevation/gnv/math/Interpolation2D.java: 
+	  Use local variable debug instead of asking log.isDebugEnabled() 
+	  more than once.
+
+	* src/main/java/de/intevation/gnv/math/XYColumn.java: extrapolate
+	  with boundary values.
+
+	* src/main/java/de/intevation/gnv/math/Interpolation3D.java:
+	  Implements a 3D interpolation called 'Profilschnitt' along a 
+	  track similiar to the 'Horizontaler Schnittprofil' which takes 
+	  all k layers into account. 
+
+	  At the interpolated (x, y) points columns of parameter values 
+	  from surface to ground are interpolated. To do so the four 
+	  next neighbor of that columns are figured out. Four
+	  cubic splines are fitted through these parameter values 
+	  of these neighbors. Now its possible to continuous eval
+	  the parameter on each. Every entry in the interpolated column
+	  is interpolated bilinear from the four cubic spline interpolated
+	  neighbor values at the respective depth.
+
+	  The result is stored into a double valued raster. NaN values
+	  indicates interpolation gaps.
+
 2009-12-23	Sascha L. Teichmann	<sascha.teichmann@intevation.de>
 
 	* src/main/java/de/intevation/gnv/math/XYColumn.java: Added a method