Need help importing DEM data

Hi,

I'm a new grass user and would like to import some USGS DEM data.
This is what I have done:

downloaded las_vegas-e.gz from edcftp.cr.usgs.gov/pub/data/DEM/250/L

decompressed with gzip

dd if=las_vegas-e ibs=10240 | m.dmaUSGSread top=1 bottom=1201 \
left=1 right=1201 output=las_vegas-e.dat logfile=las_vegas-e.log

m.rot input=las_vegas-e.dat output=las_vegas-e.dem \
rows=1201 cols=1201 bpc=2

r.in.ll input=las_vegas-e.dem output=dem.utm dimension=1201,1201 \
bpc=2 res=3,3 corner=sw,34N,119W spheroid=wgs72

g.region rast=dem.utm
d.rast dem.utm

All that is displayed is a single very narrow strip.
I'd appreciate some pointers to where I am going wrong. I've tried
get information from moon but can't seem to download any of the archive
material or help docs.

Thanks.

*******************************************************************
James Curry
Lawrence Livermore National Laboratory
P.O. Box 808, MS: L-183
Livermore, California 94550

(510) 423-1106
*******************************************************************

"James" == James Curry <jcurry@llnl.gov> writes:

    James> Hi,

    James> I'm a new grass user and would like to import some USGS DEM
    James> data. This is what I have done:

    James> downloaded las_vegas-e.gz from
    James> edcftp.cr.usgs.gov/pub/data/DEM/250/L decompressed with
    James> gzip

    James> dd if=las_vegas-e ibs=10240 | m.dmaUSGSread top=1 bottom=1201 \
    James> left=1 right=1201 output=las_vegas-e.dat logfile=las_vegas-e.log

These are not the options I use with dd. From
<ftp://edcftp.cr.usgs.gov/pub/data/DEM/250/00README&gt;:

    RECORD DELIMITERS:
    The DEM files do not contain record delimiters. You can add delimiters by
    using the following UNIX command:

    dd if=inputfilename of=outputfilename ibs=4096 cbs=1024 conv=unblock

I'm not sure that would explain your results, though. Is the strip
about 1/10th the correct size (1024/10240)?

    James> [deleted stuff looks OK ...]

    James> All that is displayed is a single very narrow strip.
    James> I'd appreciate some pointers to where I am going wrong. I've tried
    James> get information from moon but can't seem to download any of the arch
ive
    James> material or help docs.

    James> Thanks.

    James> *******************************************************************
    James> James Curry
    James> Lawrence Livermore National Laboratory
    James> P.O. Box 808, MS: L-183
    James> Livermore, California 94550

    James> (510) 423-1106
    James> *******************************************************************

--
Bill Perkins
Battelle Pacific Northwest Laboratories
Environmental Technologies Division, Subsurface Flow and Transport
P.O. Box 999 MSIN K9-36
Richland, Washington, USA 99352
voice: (509) 372-6131 fax: (509) 372-6328 email: wa_perkins@pnl.gov

On Tue, 19 Mar 1996, James Curry wrote:

I'd appreciate some pointers to where I am going wrong. I've tried
get information from moon but can't seem to download any of the archive
material or help docs.

I have encountered problems in the past importing USGS DEM data. You
might want to check:
        http://www.cecer.army.mil/grass/faq.html

  --G

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