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<em>r.li.edgedensity </em>calculates:<br>
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<li> the density of all edges of patch type <em>k</em>
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<img alt="rliEdgeDensity formula1" src="rliEdgeDensity_formula1.png">
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<li> the density of all edges in the sampling area if <em>k</em> is
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<img alt="rliEdgeDensity formula2" src="rliEdgeDensity_formula2.png">
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<li><b>k</b>: patch type</li>
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<li><b>m</b>: number of patch types</li>
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<li><b>n</b>: number of edge segments of patch type k</li>
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<li><b>e<small><small>ik </small></small></b>:total edge length in
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the landscape involving patch type k</li>
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<li> <b>Area</b>: total landscape area</li>
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Do not use absolute path names for the <b>output</b> map/file.
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If the "moving window" method was selected in <b>r.li.setup</b>, then the
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output will be a raster map, otherwise an ASCII file will be generated in
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the <tt>$HOME/.r.li/output/</tt> folder.
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<!-- TODO: verify next: -->
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If the input raster map contains only NULL values then <em>r.li.edgedensity</em>
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consider to have 0 patches.<br>
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If area is 0 <em>r.li.edgedensity</em> returns -1; this is only possible if input
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If you want to change these -1 values to NULL, run subsequently on the resulting map:
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<div class="code"><pre>
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r.null setnull=-1 map=my_map
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after index calculation.
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To calculate the edge density index on map <em>my_map</em>, using
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<em>my_conf</em> configuration file (previously defined with
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<em>r.li.setup</em>) and saving results in <em>my_out</em>, run:
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<div class="code"><pre>
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r.li.edgedensity map=my_map conf=my_conf output=my_out
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To calculate edge density index of patch_type 34, using
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"my_conf" configuration file and on map "my_map", saving results in "my_out"
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<div class="code"><pre>
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r.li.edgedensity map=my_map conf=my_conf output=my_out patch_type=34
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Forest map (Spearfish sample dataset) example:
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<div class="code"><pre>
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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.edgedensity map=forests conf=movwindow7 out=forests_edgedens_mov7
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r.univar forests_edgedens_mov7
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<a href="r.li.html">r.li</a> - package overview<br>
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<a href="r.li.setup.html">r.li.setup</a>
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McGarigal, K., and B. J. Marks. 1995. FRAGSTATS: spatial pattern
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analysis program for quantifying landscape structure. USDA For. Serv.
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Gen. Tech. Rep. PNW-351. (<a href="http://treesearch.fs.fed.us/pubs/3064">PDF</a>)
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Serena Pallecchi student of Computer Science University of Pisa (Italy).<br>
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Commission from Faunalia Pontedera (PI), Italy (www.faunalia.it)
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<i>Last changed: $Date: 2014-02-19 01:26:04 +0100 (Wed, 19 Feb 2014) $</i>