NAME

       r.li.edgedensity   -  Calculates  edge  density index on a raster map, using a 4 neighbour
       algorithm

KEYWORDS

       raster, landscape structure analysis, patch index

SYNOPSIS

       r.li.edgedensity
       r.li.edgedensity --help
       r.li.edgedensity   [-b]   input=name    config=name    output=name     [patch_type=string]
       [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui]

   Flags:
       -b
           Exclude border edges

       --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

       patch_type=string
           The value of the patch type
           It can be integer, double or float; it will be changed in function of map type

DESCRIPTION

       r.li.edgedensity calculates:

           •   the density of all edges of patch type k , or

           •   the density of all edges in the sampling area if k is not specified,

       with:

           •   k: patch type

           •   m: number of patch types

           •   n: number of edge segments of patch type k

           •   eik :total edge length in the landscape involving patch type k

           •   Area: total landscape area

       The unit is meters per hectare.

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\GRASS7\r.li\output\            (MS-Windows)             or
       $HOME/.grass7/r.li/output/ (GNU/Linux).

       If the input raster map contains only NULL values then r.li.edgedensity consider to have 0
       patches.
       If area is 0 r.li.edgedensity returns NULL; this is  only  possible  if  input  raster  is
       masked.

EXAMPLES

       To  calculate  the  edge  density  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.edgedensity input=my_map conf=my_conf output=my_out
       To calculate edge density index of patch_type 34, using "my_conf" configuration  file  and
       on map "my_map", saving results in "my_out" file run:
       r.li.edgedensity input=my_map conf=my_conf output=my_out patch_type=34

       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.edgedensity input=forests conf=movwindow7 out=forests_edgedens_mov7
       r.univar forests_edgedens_mov7

       Forest map (North Carolina sample dataset) example:
       g.region raster=landclass96 -p
       r.mapcalc "forests = if(landclass96 == 5, 1, null() )"
       r.li.edgedensity input=forests conf=movwindow7 out=forests_edgedensity_mov7
       # verify
       r.univar forests_edgedensity_mov7
       r.to.vect input=forests output=forests type=area
       d.mon wx0
       d.rast forests_edgedensity_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)
       Markus Metz

       Last changed: $Date: 2015-08-25 00:15:04 +0200 (Tue, 25 Aug 2015) $

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

       © 2003-2016 GRASS Development Team, GRASS GIS 7.0.3 Reference Manual