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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:


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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