.TH r.li.mpa 1grass "" "GRASS 6.4.4" "Grass User's Manual"
.SH NAME
\fI\fBr.li.mpa\fR\fR  - Calculates mean pixel attribute index on a raster map
.SH KEYWORDS
raster, landscape structure analysis, patch index
.SH SYNOPSIS
\fBr.li.mpa\fR
.br
\fBr.li.mpa help\fR
.br
\fBr.li.mpa map\fR=\fIname\fR \fBconf\fR=\fIname\fR \fBoutput\fR=\fIname\fR  [\-\-\fBoverwrite\fR]  [\-\-\fBverbose\fR]  [\-\-\fBquiet\fR] 
.SS Flags:
.IP "\fB\-\-overwrite\fR" 4m
.br
Allow output files to overwrite existing files
.IP "\fB\-\-verbose\fR" 4m
.br
Verbose module output
.IP "\fB\-\-quiet\fR" 4m
.br
Quiet module output
.PP
.SS Parameters:
.IP "\fBmap\fR=\fIname\fR" 4m
.br
Name of input raster map
.IP "\fBconf\fR=\fIname\fR" 4m
.br
Configuration file
.IP "\fBoutput\fR=\fIname\fR" 4m
.br
Name for output raster map
.PP
.SH DESCRIPTION
\fIr.li.mpa\fR (mean pixel attribute) calculates the average value of the
attribute of all the non-null cells in the sampling area as:
.br
with:
.br
.RS
.IP
\fBi\fR: attribute
.IP
\fBm\fR: number of non-null attributes in the sampling area 
.IP
\fBwi\fR: number of cells of attribute i
.IP
\fBsize\fR: size of sampling area (in cells)
.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.mpa\fR considers to
have 0 patches.
.br
If area is 0 \fIr.li.mpa\fR returns -1; it is possible only if the
raster is masked 
.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
.br
.DE
\fR
after index calculation.
.SH EXAMPLES
To calculate the mean pixel attribute 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.mpa map=my_map conf=my_conf output=my_out
.br
.DE
\fR
.PP
Forest map (Spearfish sample dataset) example:
\fC
.DS
.br
g.region rast=landcover.30m \-p
.br
r.mapcalc "forests = if(landcover.30m >= 41 && landcover.30m <= 43,1,null())"
.br
r.li.mpa map=forests conf=movwindow7 out=forests_mpa_mov7
.br
r.univar forests_mpa_mov7
.br
.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
Serena Pallecchi student of Computer Science University of Pisa (Italy).
.br
Commission from Faunalia Pontedera (PI), Italy (www.faunalia.it)
.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