How do I calcualte the Curvature of contours lines

Discussion created by jgui001 on Sep 6, 2012
I have a raster which has the intensity readings for the local magnetic field.  What I want to do is work out how curvy the field is at each point. I tried using the curvature tool but unfortunately this was not successful as most points go a zero (or close to it) curvature value. This was because the surrounding points did not change that much despite over larger distances the field being very curvy. I could reduce the raster now to a coarser resolution but that will cause a loss of information which we cannot afford and in places where the field strength changes rapidly the resulting values would not be representatives of the field.

The best I think I can do is create contours and then measure how curvy the contours are in 20-60m intervals. Then using the resulting point data calculate a new raster file.  Does this sound like a reasonable approach and are there a set of tools/scripts that can do this? I have already generated the contour lines, I???m just at a loss on how to do the next step.