Merging DEM's

[Eric Mitchell]

I have had good luck importing the 7.5min USGS DEM data,
with the help of the utilities listed below.  There is 
also a sdtsutil package available from Sol, which has 
many SDTS conversion routines.  I have had the best luck 
with sdts2xyz, and importing the resulting file with
r.in.ascii.  The trickiest thing to do (for me) was 
setting the right region information.

Unfortunately, I've left the recipe for importing the 
data at home, but will post it if people are interested.
It could be a potentially useful addition to the FAQ...


"aanderson = (A.N. Anderson - Idaho Research Software)" wrote:
> 
> I have had some success at reading 7.5 min USGS DEMS, using
> Sol Katz's routines which I had to modify to fix some alignment
> problems when joining maps together. I have also been able to
> use the DLG's from the same source.
> 
> Have you tried Katz's stuff?
> 
> try:
> 
> http://ftp.blm.gov/pub/gis/sdts/dem/old/sdts2dem.tgz
> 
> which also use the fips123 lib at
> 
> http://sdts.er.usgs.gov/pub/sdts/software/fips123/fips123*.gz
> 
> Good luck
> 
> On Fri, 08 Oct 1999, you wrote:
> > I'm having nothing but trouble trying to import USGS DEM's, either 7.5 type
> > or 1 degree versions, into my GRASS5 using m.dem.extract.  Errors include
> > "data not found in correct file" and m.rot90 subroutine not finding file to
> > work on.
> >
> > Anyone out there who uses this command regularly I could talk to in an
> > effort to get it to work for me?  Many thanks, tom at bluesky.org
> --
>                         From Al Anderson
> _______________________________________________________
> - Anything NOT worth doing..is NOT worth doing well! AA
> _______________________________________________________

-- ebm
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| Eric B. Mitchell        mailto:ricdude at toad.net |
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