NAME

       r.li.mpa  - Calculates mean pixel attribute index on a raster map

KEYWORDS

       raster, landscape structure analysis, patch index

SYNOPSIS

       r.li.mpa
       r.li.mpa --help
       r.li.mpa   input=name   config=name   output=name   [--overwrite]   [--help]   [--verbose]
       [--quiet]  [--ui]

   Flags:
       --overwrite
           Allow output files to overwrite existing files

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       input=name [required]
           Name of input raster map

       config=name [required]
           Configuration file

       output=name [required]
           Name for output raster map

DESCRIPTION

       r.li.mpa (mean pixel attribute) calculates the average value of the attribute of  all  the
       non-null cells in the sampling area as:
       with:

           •   i: attribute

           •   m: number of non-null attributes in the sampling area

           •   wi: number of cells of attribute i

           •   size: size of sampling area (in cells)

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\GRASS7\r.li\output\            (MS-Windows)             or
       $HOME/.grass7/r.li/output/ (GNU/Linux).

       If  the  input  raster  map  contains  only  NULL values then r.li.mpa considers to have 0
       patches.
       If area is 0 r.li.mpa returns -1; it is possible only if the raster is masked
       If you want to change these -1 values to NULL, run subsequently on the resulting map:
       r.null setnull=-1 input=my_map
       after index calculation.

EXAMPLES

       To calculate the mean pixel attribute 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.mpa input=my_map conf=my_conf output=my_out

       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.mpa input=forests conf=movwindow7 out=forests_mpa_mov7
       r.univar forests_mpa_mov7

       Forest map (North Carolina sample dataset) example:
       g.region raster=landclass96 -p
       r.mapcalc "forests = if(landclass96 == 5, 1, null() )"
       r.li.mpa input=forests conf=movwindow7 out=forests_mpa_mov7
       # verify
       r.univar forests_mpa_mov7
       r.to.vect input=forests output=forests type=area
       d.mon wx0
       d.rast forests_mpa_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 (www.faunalia.it)
       Markus Metz

       Last changed: $Date: 2014-12-19 22:55:37 +0100 (Fri, 19 Dec 2014) $

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