NAME

       r.li.simpson  - Calculates Simpson’s diversity index on a raster map

KEYWORDS

       raster, landscape structure analysis, diversity index

SYNOPSIS

       r.li.simpson
       r.li.simpson --help
       r.li.simpson  input=name  config=name  output=name   [--overwrite]   [--help]  [--verbose]
       [--quiet]  [--ui]

   Flags:
       --overwrite
           Allow output files to overwrite existing files

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       input=name [required]
           Name of input raster map

       config=name [required]
           Configuration file

       output=name [required]
           Name for output raster map

DESCRIPTION

       r.li.simpson calculates the "Simpson’s diversity index" as:
       with:

           •   i: patch type

           •   m: number of different patch types

           •   pi: proportional abundance of patch type i

NOTES

       Do not use absolute path names for the config and  output  file/map  parameters.   If  the
       "moving  window"  method  was selected in g.gui.rlisetup, then the output will be a raster
       map,    otherwise    an    ASCII    file    will    be    generated    in    the    folder
       C:\Users\userxy\AppData\Roaming\GRASS8\r.li\output\             (MS-Windows)            or
       $HOME/.grass8/r.li/output/ (GNU/Linux).

       If the input raster map contains only NULL values then r.li.simpson returns NULL.

EXAMPLES

       To calculate Simpson’s diversity index on map my_map,  using  my_conf  configuration  file
       (previously defined with g.gui.rlisetup) and saving results in my_out, run:
       r.li.simpson input=my_map conf=my_conf output=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.simpson input=forests conf=movwindow7 out=forests_simpson_mov7
       r.univar forests_simpson_mov7

       Forest map (North Carolina sample dataset) example:
       g.region raster=landclass96 -p
       r.mapcalc "forests = if(landclass96 == 5, 1, null() )"
       r.li.simpson input=forests conf=movwindow7 out=forests_simpson_mov7
       # verify
       r.univar forests_simpson_mov7
       r.to.vect input=forests output=forests type=area
       d.mon wx0
       d.rast forests_simpson_mov7
       d.vect forests type=boundary

SEE ALSO

        r.li - package overview
       g.gui.rlisetup

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)

SOURCE CODE

       Available at: r.li.simpson source code (history)

       Accessed: Tuesday Jun 27 11:13:02 2023

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       © 2003-2023 GRASS Development Team, GRASS GIS 8.3.0 Reference Manual