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: Monday Apr 01 03:07:51 2024

       Main index | Raster index | Topics index | Keywords index | Graphical index | Full index

       © 2003-2024 GRASS Development Team, GRASS GIS 8.3.2 Reference Manual

GRASS 8.3.2                                                                                 r.li.simpson(1grass)