On Mon, Jan 13, 2014 at 3:30 PM, Markus Neteler <[email protected]> wrote: > On Mon, Jan 13, 2014 at 12:39 PM, Johannes Radinger > <[email protected]> wrote: >> Dear all, >> >> I just tried r.clump on a rastarized river with alternating patches of good >> and bad habitat (values 1 and 2). However, due to its linear structure, many >> cells of the same habitat patch are often only diagonally connected. So this >> is a case where r.clump does not work (as stated in its manual). >> >> So, as a suggestion, it'd be nice if also diagonal cells could be considered >> by r.clump (e.g. by setting a flag). > > Note that there is a more modern version here: > > http://grasswiki.osgeo.org/wiki/AddOns/GRASS_6#r.clump2 > > http://grasswiki.osgeo.org/wiki/AddOns/GRASS7/raster#r.clump2
I would recommend r.clump4p over r.clump2. r.clump4p is the fastest of the three, even without parallelisation. Note that r.clump4p, like r.clump, also clumps NULL cells, whereas only r.clump2 ignores NULL cells. > > Markus > _______________________________________________ > grass-user mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/grass-user _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
