[GRASS-user] Generating DEM from bare ground LIDAR data: v.surf.idw or v.surf.bspline ?

[stephen sefick]

I have a multitude of DEMs to generate at 1m resolution.  Are there
any references that compare v.surf.idw and v.surf.bspline?  Any advice
or experience with either of these two modules would be helpful.
Which one of these modules creates the most accurate representation of
the surface.  This will be with NC data- in fact the same 2001 data
that is included in the new GRASS dataset.  I am working on a project
in NC if this helps.  Thank you for all of your help, and I will
provide any information that you may need.  Also, if I use
v.surf.bspline is the 1.5*point average point spacing still the rule
of thumb (the point spacing is found with running v.surf.bspline with
the -e flag?).  Thank you so much for all of your help.

-- 
Stephen Sefick
____________________________________
| Auburn University                                   |
| Department of Biological Sciences           |
| 331 Funchess Hall                                  |
| Auburn, Alabama                                   |
| 36849                                                    |
|___________________________________|
| sas0025 at auburn.edu                             |
| http://www.auburn.edu/~sas0025             |
|___________________________________|

Let's not spend our time and resources thinking about things that are
so little or so large that all they really do for us is puff us up and
make us feel like gods.  We are mammals, and have not exhausted the
annoying little problems of being mammals.

                                -K. Mullis

"A big computer, a complex algorithm and a long time does not equal science."

                              -Robert Gentleman