.TH r.li.renyi 1grass "" "GRASS 6.4.4" "Grass User's Manual"
.SH NAME
\fI\fBr.li.renyi\fR\fR  - Calculates Renyi's diversity index on a raster map
.SH KEYWORDS
raster, landscape structure analysis, diversity index
.SH SYNOPSIS
\fBr.li.renyi\fR
.br
\fBr.li.renyi help\fR
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\fBr.li.renyi map\fR=\fIname\fR \fBconf\fR=\fIname\fR \fBalpha\fR=\fIstring\fR \fBoutput\fR=\fIname\fR  [\-\-\fBoverwrite\fR]  [\-\-\fBverbose\fR]  [\-\-\fBquiet\fR] 
.SS Flags:
.IP "\fB\-\-overwrite\fR" 4m
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Allow output files to overwrite existing files
.IP "\fB\-\-verbose\fR" 4m
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Verbose module output
.IP "\fB\-\-quiet\fR" 4m
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Quiet module output
.PP
.SS Parameters:
.IP "\fBmap\fR=\fIname\fR" 4m
.br
Name of input raster map
.IP "\fBconf\fR=\fIname\fR" 4m
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Configuration file
.IP "\fBalpha\fR=\fIstring\fR" 4m
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Alpha value is the order of the generalized entropy
.IP "\fBoutput\fR=\fIname\fR" 4m
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Name for output raster map
.PP
.SH DESCRIPTION
\fIr.li.renyi\fR calculates the "Renyi's diversity index" as:
.br
with:
.RS
.IP
\fBH\fR: Renyi entropy
.IP
\fBalpha\fR: order of the generalized entropy
.IP
\fBi\fR: ith class
.IP
\fBS\fR: number of classes
.IP
\fBpi\fR: proportion of the landscape occupied by class i
.RE
.SH NOTES
Do not use absolute path names for the \fBoutput\fR map/file.
If the "moving window" method was selected in \fBr.li.setup\fR, then the
output will be a raster map, otherwise an ASCII file will be generated in
the $HOME/.r.li/output/ folder.
.PP
If the input raster map contains only NULL values then \fIr.li.renyi\fR
returns -1.
.br
If you want to change these -1 values to NULL, run subsequently on the resulting map:
\fC
.DS
.br
r.null setnull=-1 map=my_map
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.DE
\fR
after index calculation.
.SH EXAMPLES
To calculate Renyi's diversity index on map \fImy_map\fR, using
\fImy_conf\fR configuration file (previously defined with
\fIr.li.setup\fR) and saving results in \fImy_out\fR, run:
\fC
.DS
.br
r.li.renyi map=my_map conf=my_conf output=my_out alpha=0.6
.br
.DE
\fR
.PP
Forest map (Spearfish sample dataset) example:
\fC
.DS
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g.region rast=landcover.30m \-p
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r.mapcalc "forests = if(landcover.30m >= 41 && landcover.30m <= 43,1,null())"
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r.li.renyi map=forests conf=movwindow7 out=forests_renyi_mov7_a06 alpha=0.6
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r.univar forests_renyi_mov7_a06
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.DE
\fR
.SH SEE ALSO
\fI
r.li - package overview
.br
r.li.setup
\fR
.SH 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)
.SH AUTHORS
Luca Delucchi and Duccio Rocchini, Fondazione E. Mach (Italy), based on
the \fIr.li.shannon\fR code developed by Serena Pallecchi student of
Computer Science University of Pisa (Italy).
.br
.PP
\fILast changed: $Date: 2014-02-19 01:26:04 +0100 (Wed, 19 Feb 2014) $\fR
.PP
Full index
.PP
© 2003-2014 GRASS Development Team