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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 input=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:
- input=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
![](rliEdgeDensity_formula1.png)
or
- the density of all the edge in the sampling area if i isn't specified
![](rliEdgeDensity_formula2.png)
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 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
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: 2010-04-08 01:24:34 -0700 (Thu, 08 Apr 2010) $
Main index - raster index - Full index
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