NAME

       r.li.cwed  - Calculates contrast weighted edge density index on a raster map

KEYWORDS

       raster, landscape structure analysis, patch index

SYNOPSIS

       r.li.cwed
       r.li.cwed help
       r.li.cwed   map=name   conf=string  path=string  output=name   [--overwrite]   [--verbose]
       [--quiet]

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

       --verbose
           Verbose module output

       --quiet
           Quiet module output

   Parameters:
       map=name
           Name of input raster map

       conf=string
           Configuration file

       path=string
           Input file that contains the weight to calculate the index

       output=name
           Name for output raster map

DESCRIPTION

       r.li.cwed (contrast weighted edge density) calculates the edge density between patch types
       specified:

       with:

                      k: attribute

                      m: number of non-null attributes in the sampling area

                      eik: total length of edge in landscape between patch types i and k

                      dik: dissimilarity (edge contrast weight) between patch types i and k

                      Area: total landscape area
       The  input  file  have a row for each couple of patch type that we want to consider in the
       calculation. Each row must to have this syntax:
       patchType1,patchType2,dissimilarityBetweenPatchType1andPatchType2

EXAMPLES

       To calculate mean pixel attribute index on map my_map, using  my_conf  configuration  file
       and saving results in my_out file run:

       r.li.cwed map=my_map conf=my_conf path=my_file output=my_out

       Example of input file: 12,16,0.65
       44,123,0.32
       56,12,0.54
       23,66,0.99

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 the raster is full of null value it is considered to have 0 patch and CWED=0.  If  Area
       is 0 r.li.cwed returns -1. This is possible only if the map is masked.
       If you want to have null values instead run

       r.null setnull=-1 map=my_map
        after index calculation.

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.

SEE ALSO

       r.li package overview
       r.li.daemon
       r.li.setup

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 02:13:05 -0700 (Tue, 16 Aug 2011) $

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       © 2003-2013 GRASS Development Team