r.li.edgedensity

Langue: en

Autres versions - même langue

Version: 369955 (fedora - 01/12/10)

Section: 1 (Commandes utilisateur)

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 map=name conf=string output=name [patch_type=string] [--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
output=name

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 the edge of patch i

or

 the density of all the edge in the sampling area if i isn't specified

with:

k: patch type
m: number of patch type

 
n: number of edge segment of patch type k
eik :total length of edge in landscape involving patch type k

 Area: total landscape area

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.

EXAMPLES

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

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 input raster is full of null values r.li.edgedensity consider to have 0 patch.
If area is 0 r.li.edgedensity returns -1; this is possible only if input raster is masked. If you want to have null values instead run
r.null setnull=-1 map=my_map
after index calculation.

SEE ALSO

r.li

AUTHORS

Serena Pallecchi student of Computer Science University of Pisa (Italy).
Commission from Faunalia Pontedera (PI), Italy (www.faunalia.it)

BUGS

Please send bugs reports to pallecch@cli.di.unipi.it

Last changed: $Date: 2007-02-08 17:52:53 +0100 (Thu, 08 Feb 2007) $

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