[GRASS-user] r.clump alternative

[Markus Metz]

Hi all,

in grass-addons there is now an alternative for r.clump, written for 
grass7, that is, it doesn't work with grass6x.

svn co https://svn.osgeo.org/grass/grass-addons/grass7/raster/r.clump2 
raster/r.clump2

Differences to r.clump are:
- NULL cells are preserved
- option to consider only edge cells, ignoring diagonal cells, default 
is looking at all 8 neighbours (ignoring diagonal cells is default in 
r.clump, can't be changed there)
- input map categories are not preserved, r.clump2 clumps everything 
together it can
- about 10x faster

For developers: this is not a modification of r.clump, it is written 
anew from scratch. The options are taken from r.clump, some tools 
developed by Chuck Ehlschlaeger and Michael Shapiro are taken from 
r.watershed, the clumping algorithm is a simplified DJP algorithm (my 
own idea, otherwise not present in grass AFAIK).

Markus M