r.li.simpson(1)

NAME
r.li.simpson

DESCRIPTION
r.li.simpson calculates the "simpson's diversity index" as:
with:

        i: patch type

        m: number of patch type

        pi: proportion of the landscape occupied by patch type i

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.

EXAMPLES
To calculate simpson's diversity index on map my_map, using my_conf configuration file and saving results in my_out file run:
r.li.simpson map=my_map conf=my_conf output=my_out

NOTES
Do not use absolute path names for output files. They are raster if moving window disposition was selected, otherwise they are in ~/.r.li/output folder.
If input raster is full of null values r.li.simpson returns -1.
If you want to have null values instead run
r.null setnull=-1 map=my_map
after index calculation.

SEE ALSO
r.li

AUTHORS
Serena Pallecchi student of Computer Science University of Pisa (Italy).
Commission from Faunalia Pontedera (PI), Italy (www.faunalia.it)

Last changed: $Date: 2011-08-16 11:13:05 +0200 (Tue, 16 Aug 2011) $

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