Re: r.in.sunrast command

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Re: r.in.sunrast command

William R. Lamb sys.adm
Yo fellow grass users:
I have not been able to figure out how to get DEM data into GRASS4.0 if
you
do not have a local tape drive.  I have to dump nine track tapes on a
Vax or Amdahl cross-campus :-( and then bring them to my workstation
across our net.  The grass4.0 command m.dem.extract wants a tape drive
locally.  How can this be
bypassed?  I would really like to save myself from writing a program to
do this
if someone has done it before.
My next question is how does one make a DEM (and subsequent slope cell
map)from a grid of point elevations.  Thanks in advance for your
insight.

William Lamb
Remote Sensing/GIS Laboratory
Dept. of Forest Science
Texas A&M University
[hidden email]
(409) 845-9425

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Re: r.in.sunrast command

Jinn-Guey Lay
>...
>across our net.  The grass4.0 command m.dem.extract wants a tape drive
>locally.  How can this be bypassed?  I would really like to save myself
>from writing a program to do this if someone has done it before.

I don't think tape drive is a must for this command. I have my DEM data
in disk as a file, by specifying the file name as input in the command
line, I found that m.dem.extract can read from the DEM file. However,
I couldn't use this command to input my DEM file correctly. I am not sure
whether this has something to do with block size or the different formats
between DEMs.

Instead of using m.dem.extract, I used r.in.ascii to input my DEM data
into GRASS. I converted my DEM into Idrisi image format using a utility
written by one of my colleagues. In fact, any ASCII text file will do. By
adding some header information to the ASCII file, the r.in.ascii command
had no problem in generating a raster file.

>William Lamb
>Remote Sensing/GIS Laboratory
>Dept. of Forest Science
>Texas A&M University

Jinn-Guey Lay
Department of Geography
University of Hawaii at Manoa