How to rotate a map

Michael Shapiro shapiro at
Wed Aug 4 21:31:49 EDT 1993

In <9308021604.AA11909 at> moupu at writes:

>Dear members,

>I tried to use m.rot90 to rotate a raster map and it tells that the raster
>map I wanted to totate does not existed. Why does this happen?

m.rot90 doesn't process GRASS raster maps. It is a tool that
rotates non-grass simple 2D matrix files. You can use it
to rotate a raster map (if you know what you are doing).
You would have to uncompress the raster map (r.compress), then use m.rot90
on the uncompressed file under the cell/ directory. Then you
would have to modify the cell header (with or by hand
using an editor) to interchage the rows and cols.

Michael Shapiro               shapiro at
U.S. Army CERL                (217) 373-7277
P.O. Box 9005 
Champaign, Ill. 61826-9005

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