[GRASS-user] problems using r.proj with large data set

[Jerry Nelson]

I am working with SRTM elevation for the Horn of Africa. The data comes in
chunks, which I have patched together to cover all the countries I'm
interested in (South to Uganda and west to Ethiopia). The data are
originally in lat-long but I want to calculate slope so my understanding is
that I need to project. I choose utm 37N as being roughly in the center of
the region and then extend the bounds of the working region to include all
the countries. 

 

I'm using grass63 that I compiled on a machine running CentOS, which is a
version of Redhat. The machine has 2 gb of memory. The command runs for
awhile and then stops, sometimes with a complain about memory or sometimes
with the word Killed. Any suggestions greatly appreciated!

 

Jerry

 

r.proj input=AfricaHornElev location=world mapset=PERMANENT
output=AfricaHornElev method=cubic 

 

Input Projection Parameters: +proj=longlat +a=6378137 +rf=298.257223563
+no_defs Input Unit Factor: 1

 

Output Projection Parameters: +proj=utm +zone=37 +a=6378137
+rf=298.257223563 +n o_defs Output Unit Factor: 1

Input:

Cols:   25128 (25200)

Rows:   24696 (27600)

North: 15.580000 (18.000000)

South: -5.000000 (-5.000000)

West:  31.000000 (31.000000)

East:  51.940000 (52.000000)

ew-res: 0.000833

ns-res: 0.000833

 

Output:

Cols:   19262 (20328)

Rows:   19223 (19507)

North: 1722315.000000 (1722315.000000)

South: -566189.703183 (-600000.000000)

West:  -393095.238095 (-520000.000000)

East:  1900000.000000 (1900000.000000)

ew-res: 119.047619

ns-res: 119.050341

Allocating memory and reading input map...

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