Need help on extracting DEM data!!

Wang Song wang at
Thu Nov 11 18:24:41 EST 1993

Subbarao Vedula wrote:

I was trying to read DEM data from 1/2" tape drive into my SUN account using
"m.dem.extract" command. I gave the input file name as  /dev/rmt0 (1600bpi)
and blocksize as 4096. Then its saying
"Reading Elevation Tape...     
ERROR: error reading tape".

When I ran "m.dem.examine", it gave the following results:


PHENIX CITY - W                  AL,GA          NI

min elevation: 45.000000  max elevation: 305.000000

ns_res: 0.000000  ew_res: 0.000000
# of columns in file =   809773872

	(1) Try to use UNIX "dd" comand read DEM from tape to a file. 
	(2) Use "m.dem.extract" to read DEM from the disk file.
	(3) Check your blocksize, make sure it is correct. You can use UNIX
	"tcopy" command to check out the block size from tape.

Song Wang

wang at

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