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+<h2>DESCRIPTION</h2>
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+
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+<em>t.rast.aggregate</em> temporally aggregates space time raster datasets by a specific temporal granularity.
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+The granularity can be <em>seconds, minutes, hours, days, weeks, months</em> and <em>years</em>.
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+Mixing of granularities is not supported.
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+<p>
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+This module is sensitive to the current region and mask settings, hence spatial extent and spatial resolution.
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+In case the registered raster maps of the input space time raster dataset
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+have different spatial resolutions, the default nearest neighbour resampling method is used for
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+runtime spatial aggregation.
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+
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+<h2>NOTES</h2>
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+
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+The raster module <em>r.series</em> is used internally. Hence all aggregate
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+methods of <em>r.series</em> are supported. See the <a href="r.series.html">r.series</a> manpage
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+for details.
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+<p>
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+This module will shift the start date for each aggregation process depending on the
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+provided temporal granularity. The following shifts will performed:
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+
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+<ul>
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+ <li><em>granularity years</em>: will start at the first of January, hence 14-08-2012 00:01:30 will be shifted to 01-01-2012 00:00:00</li>
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+ <li><em>granularity months</em>: will start at the first day of a month, hence 14-08-2012 will be shifted to 01-08-2012 00:00:00</li>
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+ <li><em>granularity weeks</em>: will start at the first day of a week (monday), hence 14-08-2012 01:30:30 will be shifted to 13-08-2012 01:00:00</li>
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+ <li><em>granularity days</em>: will start at the first hour of a day, hence 14-08-2012 00:01:30 will be shifted to 14-08-2012 00:00:00</li>
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+ <li><em>granularity hours</em>: will start at the first minute of a hour, hence 14-08-2012 01:30:30 will be shifted to 14-08-2012 01:00:00</li>
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+ <li><em>granularity minutes</em>: will start at the first second of a minute, hence 14-08-2012 01:30:30 will be shifted to 14-08-2012 01:30:00</li>
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+</ul>
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+
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+<h2>EXAMPLE</h2>
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+
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+In this example we create 7 raster maps that will be registered in a single space time
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+raster dataset named <em>precipitation_daily</em> using a daily temporal granularity.
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+The names of the raster maps are stored in a text file that is used for raster map registration.
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+<p>
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+The space time raster dataset <em>precipitation_daily</em> with daily temporal granularity
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+will be aggregated to weekly precipitation resulting in the output space time raster dataset
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+<em>precipitation_weekly</em>. The base name of the new generated raster maps is <em>prec_weekly</em>, the
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+granularity is 1 week. The aggregation method is set to <em>sum</em> to accumulate the precipitation values
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+of all raster maps in a week. The sampling option assures that only raster maps that are
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+temporally during a week will be considered for computation:
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+
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+<div class="code"><pre>
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+
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+MAPS="map_1 map_2 map_3 map_4 map_5 map_6 map_7"
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+
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+for map in ${MAPS} ; do
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+ r.mapcalc --o expr="${map} = 1"
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+ echo ${map} >> map_list.txt
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+done
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+
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+t.create type=strds temporaltype=absolute \
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+ output=precipitation_daily \
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+ title="Daily precipitation" \
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+ description="Test dataset with daily precipitation"
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+
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+t.register -i type=rast input=precipitation_daily \
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+ file=map_list.txt start=20-08-2012 increment="1 days"
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+
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+t.info type=strds input=precipitation_daily
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+
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+t.rast.aggregate input=precipitation_daily \
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+ output=precipitation_weekly \
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+ base=prec_weekly granularity="1 weeks" \
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+ method=sum sampling=during
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+
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+t.support input=precipitation_weekly \
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+ title="Weekly precipitation" \
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+ description="Aggregated precipitation dataset with weekly resolution"
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+
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+t.info type=strds input=precipitation_weekly
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+</pre></div>
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+
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+
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+<h2>SEE ALSO</h2>
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+
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+<em>
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+<a href="t.rast.aggregate.ds.html">t.rast.aggregate.ds</a><br>
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+<a href="t.rast.extract.html">t.rast.extract</a><br>
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+<a href="r.series.html">r.series</a><br>
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+<a href="g.region.html">g.region</a><br>
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+<a href="t.info.html">t.info</a><br>
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+</em>
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+
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+
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+<h2>AUTHORS</h2>
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+
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+Sören Gebbert
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+
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+<p><i>Last changed: $Date$</i>
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Soeren Gebbert