[GRASS-SVN] r41515 - grass/trunk/raster/r.external.out

[svn_grass at osgeo.org]

Author: neteler
Date: 2010-03-21 14:26:08 -0400 (Sun, 21 Mar 2010)
New Revision: 41515

Modified:
   grass/trunk/raster/r.external.out/r.external.out.html
Log:
+ example

Modified: grass/trunk/raster/r.external.out/r.external.out.html
===================================================================
--- grass/trunk/raster/r.external.out/r.external.out.html	2010-03-21 17:20:56 UTC (rev 41514)
+++ grass/trunk/raster/r.external.out/r.external.out.html	2010-03-21 18:26:08 UTC (rev 41515)
@@ -1,12 +1,33 @@
 <h2>DESCRIPTION</h2>
 
 <em>r.external.out</em> instructs GRASS to write raster maps as data
-files using GDAL.
+files (e.g. GeoTIFF) using GDAL.
 
+
+<h2>EXAMPLE</h2>
+
+The module <em>r.external.out</em> can be used along with
+<em>r.external</em> to process external geodata in GRASS
+while writing out the results directly in GeoTIFF:
+
+<div class="code"><pre>
+# register GeoTIFF file in GRASS database:
+r.external terra_lst1km20030314.LST_Day.tif out=modis_celsius
+
+# define output directory for GRASS calculation results:
+r.external.out $HOME/gisoutput/
+
+# do something (here: extract pixels &gt; 20°C), write output directly as GeoTIFF:
+r.mapcalc "warm.tif = if(modis_celsius &gt; 20, modis_celsius, null() )"
+
+# use the result elsewhere
+qgis $HOME/gisoutput/warm.tif
+</pre></div>
+
 <h2>SEE ALSO</h2>
 <em>
 <a href="r.in.gdal.html">r.in.gdal</a>,
-<a href="r.out.gdal.html">r.in.gdal</a>,
+<a href="r.out.gdal.html">r.out.gdal</a>,
 <a href="r.external.html">r.external</a>
 </em>