r.surf.sor

[Michael Shapiro]

r.surf.sor was an experiment on my part to see if  this  kind  of
technique  could  be used to generate surfaces. It is essentially
based on the method as described in Numerical Recipes  in  C.  It
makes  the  simplifying  assumption  that  the  surface satisfies
Lapace's equation:

   d^2 f     d^2 f
   -----  +  -----  = 0
   dx^2      dy^2

A more robust tool would use a more complex function as  well  as
include  stream  information. I made it available since the other
surface generating  modules  were  lacking  in  certain  regards.
Current research and development at CERL has lead to the creation
of an improvement on this basic idea. The work was  presented  at
the  GRASS  User's  Conference.  The surface is modeled by a more
complicated formula  than  the  Laplace  equation,  although  the
technique  for  "solving"  the  equation  is  not  sor - it is an
analytic solution based on a set of N nearest points.

Hopefully Dave Gerdes will elaborate on the new technique and its
availability.