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)

BUGS
Please send bugs reports to pallecch@cli.di.unipi.it

Last changed: $Date: 2007-02-08 17:52:53 +0100 (Thu, 08 Feb 2007) $

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