This index is calculated using a 4 neighbour algorithm, diagonal cells are ignored when tracing a patch.
If the sample area contains only NULL values then it is considered to
have zero patches.
r.li.patchnum input=my_map conf=my_conf out=my_out
Forest map (Spearfish sample dataset) example:
g.region raster=landcover.30m -p r.mapcalc "forests = if(landcover.30m >= 41 && landcover.30m <= 43,1,null())" r.li.patchnum input=forests conf=movwindow7 out=forests_patchnum_mov7 r.univar forests_patchnum_mov7
Forest map (North Carolina sample dataset) example:
g.region raster=landclass96 -p r.mapcalc "forests = if(landclass96 == 5, 1, null() )" r.li.patchnum input=forests conf=movwindow7 out=forests_patchnum_mov7 # verify r.univar forests_patchnum_mov7 r.to.vect input=forests output=forests type=area d.mon wx0 d.rast forests_patchnum_mov7 d.vect forests type=boundary
Last changed: $Date: 2014-12-19 22:17:36 +0100 (Fri, 19 Dec 2014) $