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NAME
r.li.renyi - Calculates Renyi's diversity index on a raster map
KEYWORDS
raster, landscape structure analysis, diversity index
SYNOPSIS
r.li.renyi
r.li.renyi help
r.li.renyi map=name conf=name alpha=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=name
- Configuration file
- alpha=string
- Alpha value is the order of the generalized entropy
- output=name
- Name for output raster map
DESCRIPTION
r.li.renyi calculates the "Renyi's diversity index" as:
with:
- H: Renyi entropy
- alpha: order of the generalized entropy
- i: ith class
- S: number of classes
- pi: proportion of the landscape occupied by class i
NOTES
Do not use absolute path names for the output map/file.
If the "moving window" method was selected in r.li.setup, then the
output will be a raster map, otherwise an ASCII file will be generated in
the $HOME/.r.li/output/ folder.
If the input raster map contains only NULL values then r.li.renyi
returns -1.
If you want to change these -1 values to NULL, run subsequently on the resulting map:
r.null setnull=-1 map=my_map
after index calculation.
EXAMPLES
To calculate Renyi's diversity index on map my_map, using
my_conf configuration file (previously defined with
r.li.setup) and saving results in my_out, run:
r.li.renyi map=my_map conf=my_conf output=my_out alpha=0.6
Forest map (Spearfish sample dataset) example:
g.region rast=landcover.30m -p
r.mapcalc "forests = if(landcover.30m >= 41 && landcover.30m <= 43,1,null())"
r.li.renyi map=forests conf=movwindow7 out=forests_renyi_mov7_a06 alpha=0.6
r.univar forests_renyi_mov7_a06
SEE ALSO
r.li - package overview
r.li.setup
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
Luca Delucchi and Duccio Rocchini, Fondazione E. Mach (Italy), based on
the r.li.shannon code developed by Serena Pallecchi student of
Computer Science University of Pisa (Italy).
Last changed: $Date: 2014-02-18 16:24:09 -0800 (Tue, 18 Feb 2014) $
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