USGS data usage in GRASS

Kemal Gurer gurer at
Tue Oct 17 08:00:00 EDT 1995

Dear GIS colleagues,

I am trying to read USGS DEM and LULC data into GRASS but data appears to
be nowhere in the display. I would appreciate if one kind soul can tell me
what I should do to correct the problem. Here is what I did step by step:

 1) got a sample data "new_york-e.gz" from in 
 2) unzipped it,
 3) applied the following conversions:

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

 and rotated it

    m.rot90 input=demtest output=demtest.r90 rows=1201  cols=1201  bpc=2

 Now, after this step I needed to set the frame of the data region. But the
 only information given for the data resides within the file in UTM
 coordinates and there is no .txt file that I can get information. Header 
 lines of the data gives the information that data has 1201 columns, its 
 resolution is 3 arc seconds and its four corners are shown as:

   Ground Coordinates of the 4 corners of the DEM:

 Finally, the last step input=demtest.r90 output=dem.utm3 dimension=1201,1201 bpc=2\
        res=3,3 corner=sw,41N,74W spheroid=wgs72

 Here, I assigned the lat-lon info from a map (roughly). When I display the
 data, however, a box of data is plotted but with zero height and
 message is displaced stating "no data". I tried a larger area to 
 give cushion regions so that I can guarantee to capture the data; it did 
 not work either.

 I would appreciate if one could give me an answer on how to solve the
 displaying the data. With my best regards. Sincerely.

 Kemal Gurer
 Department of Environmental Science
 Rutgers University
 New Brunswick, NJ 08903

 (908) 932 9588 

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