DESCRIPTION
r.li.mps (mean patch size) calculates the mean size of the
patches in the sampling area as:
with:
- A:sampling area size without null cells
- Npatch: number of patches
The unit of the mean size is hectare.
This index is calculated using a 4 neighbour algorithm, diagonal cells
are ignored when tracing a patch.
NOTES
Do not use absolute path names for the output map/file.
If the "moving window" method was selected in r.li.setup, then the
output will be a raster map, otherwise an ASCII file will be generated in
the $HOME/.r.li/output/ folder.
If the input raster contains NULL value cells, r.li.mps
returns 0 for these cells.
If you want to change these 0 values to NULL, run subsequently on the resulting map:
r.null setnull=0 map=my_map
after index calculation.
EXAMPLES
To calculate mean path size index on map my_map, using
my_conf configuration file (previously defined with
r.li.setup) and saving results in my_out, run:
r.li.mps map=my_map conf=my_conf output=my_out
Forest map (Spearfish sample dataset) example:
g.region rast=landcover.30m -p
r.mapcalc "forests = if(landcover.30m >= 41 && landcover.30m <= 43,1,null())"
r.li.mps map=forests conf=movwindow7 out=forests_mps_mov7
r.univar forests_mps_mov7
SEE ALSO
r.li - package overview
r.li.setup
REFERENCES
McGarigal, K., and B. J. Marks. 1995. FRAGSTATS: spatial pattern
analysis program for quantifying landscape structure. USDA For. Serv.
Gen. Tech. Rep. PNW-351. (PDF)
AUTHORS
Serena Pallecchi student of Computer Science University of Pisa (Italy).
Commission from Faunalia Pontedera (PI), Italy (www.faunalia.it)
Last changed: $Date: 2014-02-19 01:26:04 +0100 (Wed, 19 Feb 2014) $