r.lzw2z is a utility to translate GRASS floating point raster maps, from LZW
compression to deflate (zlib) compression.  It only operates on floating
point rasters that are also compressed with LZW.

The program works by taking a list of rasters, or with the '-a' flag reading
all of the fcell rasters in the current mapset, deciding if they are LZW
compressed, reads/decodes the LZW compressed file, writes a temporary file
holding a deflate compressed version and then writes the new version of the
raster DESTROYING the original.  The program can only operate rasters in the
current mapset.

It is very important that you back up your data files before running this
program.  It can fail and destroy your data.  Also, it only makes sense if
you are using a version of GRASS where LZW compression has been removed.

An alternate (and possibily preferred method) is to uncompress all of your
floating point rasters with 'r.compress -u' and a version of GRASS that
still has LZW compression.  Then, with the new version of GRASS without LZW
compression, you can do the inverse 'r.compress' to save a little space.

Eric G. Miller <egm2@jps.net> 25-Nov-2000
