r.li.edgedensity
Calculates edge density index on a raster map, using a 4 neighbour algorithm
r.li.edgedensity [-b] input=name config=name output=name [patch_type=string] [--overwrite] [--verbose] [--quiet] [--qq] [--ui]
Example:
r.li.edgedensity input=name config=name output=name
grass.script.run_command("r.li.edgedensity", input, config, output, patch_type=None, flags=None, overwrite=False, verbose=False, quiet=False, superquiet=False)
Example:
gs.run_command("r.li.edgedensity", input="name", config="name", output="name")
Parameters
input=name [required]
Name of input raster map
config=name [required]
Configuration file
output=name [required]
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
-b
Exclude border edges
--overwrite
Allow output files to overwrite existing files
--help
Print usage summary
--verbose
Verbose module output
--quiet
Quiet module output
--qq
Very quiet module output
--ui
Force launching GUI dialog
input : str, required
Name of input raster map
Used as: input, raster, name
config : str, required
Configuration file
Used as: input, file, name
output : str, required
Name for output raster map
Used as: output, raster, name
patch_type : str, optional
The value of the patch type
It can be integer, double or float; it will be changed in function of map type
flags : str, optional
Allowed values: b
b
Exclude border edges
overwrite: bool, optional
Allow output files to overwrite existing files
Default: False
verbose: bool, optional
Verbose module output
Default: False
quiet: bool, optional
Quiet module output
Default: False
superquiet: bool, optional
Very quiet module output
Default: False
DESCRIPTION
r.li.edgedensity calculates:
- the density of all edges of patch type k
, or
- the density of all edges in the sampling area if k is not specified,
with:
- k: patch type
- m: number of patch types
- n: number of edge segments of patch type k
- e_ik :total edge length in the landscape involving patch type k
- Area: total landscape area
The unit is meters per hectare.
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\GRASS8\r.li\output\
(MS-Windows) or
$HOME/.grass8/r.li/output/
(GNU/Linux).
If the input raster map contains only NULL values then
r.li.edgedensity consider to have 0 patches.
If area is 0 r.li.edgedensity returns NULL; this is only possible if
input raster is masked.
EXAMPLES
To calculate the 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.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
Forest map (Spearfish sample dataset) example:
g.region raster=landcover.30m -p
r.mapcalc "forests = if(landcover.30m >= 41 && landcover.30m <= 43,1,null())"
r.li.edgedensity input=forests conf=movwindow7 out=forests_edgedens_mov7
r.univar forests_edgedens_mov7
Forest map (North Carolina sample dataset) example:
g.region raster=landclass96 -p
r.mapcalc "forests = if(landclass96 == 5, 1, null() )"
r.li.edgedensity input=forests conf=movwindow7 out=forests_edgedensity_mov7
# verify
r.univar forests_edgedensity_mov7
r.to.vect input=forests output=forests type=area
d.mon wx0
d.rast forests_edgedensity_mov7
d.vect forests type=boundary
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 (
Markus Metz
SOURCE CODE
Available at: r.li.edgedensity source code
(history)
Latest change: Wednesday Feb 19 22:09:55 2025 in commit 5f4fa06