[GRASSLIST:7173] Gettting off the ground with v.surf.rst

Thomas Colson tom_colson at ncsu.edu
Wed Jun 15 14:52:13 EDT 2005

this may appear to be a stupid question, but I'm having a hard time
getting the "desired" output from v.surf.rst, and I don't want to run
downstairs and bother Dr. Mitasova with such a menial question....

I have a x,y,z vector of LIDAR elevation data, and I'm trying to get a
raster elevation surface based on the z col. I've tried many different
variations of the output below, with the same errors "The number of points
being used is 3
" and so forth. I'm sure this has been done many times by someone in the
know, any chance of an example command syntax so I can get this running?

v.surf.rst input=lidar3 layer=0 zcolumn=flt1 dmax=100000 dmin=10000
elev=surf7 zmult=1.0 tension=40. smooth=0.1 segmax=400 npmin=2000

Authors: original version -  H.Mitasova, L.Mitas, I. Kosinovsky, D.P. Gerdes
See manual pages for reference and publications T3

Percent complete: Reading lines from vector map ...

Reading nodes from vector map ...

Warning: strip exists with insufficient data

Warning: ignoring 348352 points -- too dense
WARNING: 3 points given for interpolation (after thinning) is less than
given NPMIN=2000
Warning : there is less than 2050 points for interpolation, no
segmentation is necessary, to run the program faster, set segmax=2050 (see

The number of points from vector file is 348355
The number of points outside of region 0
The number of points being used is 3

Processing all selected output files
will require 1612 bytes of disk space for temp files
Percent complete:

history initiated

Thomas Colson
Center For Earth Observation
North Carolina State University
Raleigh, NC
(919)515 3434
(919)673 8023
tom_colson at ncsu.edu

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