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   input=name   config=name   path=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

       path=name [required]
           Name of file that contains the weight to calculate the index

       output=name [required]
           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  contains a row for each couple of patch type that we want to consider in
       the calculation. Each row must be saved using this syntax:
       patchType1,patchType2,dissimilarityBetweenPatchType1andPatchType2

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 sample area contains only NULL values it is considered to have 0 patch and  CWED=0.
       If Area is 0 r.li.cwed returns -1.  This is only possible if the map is masked.
       If you want to change these -1 values to NULL, run subsequently on the resulting map:
       r.null setnull=-1 input=my_map
       after index calculation.

EXAMPLES

       To  calculate  the  contrast  weighted  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.cwed input=my_map conf=my_conf output=my_out \
                 path=/path/to/weights.csv
       Example for input "weights.csv" file:
       12,16,0.65
       44,123,0.32
       56,12,0.54
       23,66,0.99

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: 2014-11-28 17:25:40 +0100 (Fri, 28 Nov 2014) $

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