rotating raster maps

[ng at rti-md.com]

Here is a crude, quick and dirty unix solution.
(Assuming only North and South are reversed and not East west)

create a file with header only.
You can do this by 
r.out.ascii {map_name} | head -6 > header

In this script you will need this header file.

-------------8<-------------------------------------
#!/bin/ksh
# rotate top to bottom and vice versa
#
# Usage rotate InputMap Output_map
#
INPUT_MAP=$1
OUTPUT_MAP=$2

r.out.ascii -h ${INPUT_MAP} | nl | sort -r | cut -f2- > tmp_file
cat header tmp_file | r.in.ascii in=- out=${OUTPUT_MAP}
rm tmp_file
------------->8---------------------------------------

You could also move the tif file in xv and rotate it before importing 
in to GRASS.