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<title>GRASS GIS: v.select</title>
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<h2>NAME</h2>
<em><b>v.select</b></em> - Select features from ainput by features from binput
<h2>KEYWORDS</h2>
vector
<h2>SYNOPSIS</h2>
<b>v.select</b><br>
<b>v.select help</b><br>
<b>v.select</b> [-<b>t</b>] <b>ainput</b>=<em>name</em> [<b>atype</b>=<em>string</em>[,<i>string</i>,...]] [<b>alayer</b>=<em>integer</em>] <b>binput</b>=<em>name</em> [<b>btype</b>=<em>string</em>[,<i>string</i>,...]] [<b>blayer</b>=<em>integer</em>] <b>output</b>=<em>name</em> [<b>operator</b>=<em>string</em>] [--<b>overwrite</b>] [--<b>verbose</b>] [--<b>quiet</b>]
<h3>Flags:</h3>
<DL>
<DT><b>-t</b></DT>
<DD>Do not create attribute table</DD>
<DT><b>--overwrite</b></DT>
<DD>Allow output files to overwrite existing files</DD>
<DT><b>--verbose</b></DT>
<DD>Verbose module output</DD>
<DT><b>--quiet</b></DT>
<DD>Quiet module output</DD>
</DL>
<h3>Parameters:</h3>
<DL>
<DT><b>ainput</b>=<em>name</em></DT>
<DD>Name of input vector map</DD>
<DT><b>atype</b>=<em>string[,<i>string</i>,...]</em></DT>
<DD>Type</DD>
<DD>Feature type(s)</DD>
<DD>Options: <em>point,line,boundary,centroid,area</em></DD>
<DD>Default: <em>point,line,boundary,centroid,area</em></DD>
<DT><b>alayer</b>=<em>integer</em></DT>
<DD>Layer number</DD>
<DD>A single vector map can be connected to multiple database tables. This number determines which table to use.</DD>
<DD>Default: <em>1</em></DD>
<DT><b>binput</b>=<em>name</em></DT>
<DD>Name of input vector map</DD>
<DT><b>btype</b>=<em>string[,<i>string</i>,...]</em></DT>
<DD>Type</DD>
<DD>Feature type(s)</DD>
<DD>Options: <em>point,line,boundary,centroid,area</em></DD>
<DD>Default: <em>point,line,boundary,centroid,area</em></DD>
<DT><b>blayer</b>=<em>integer</em></DT>
<DD>Layer number</DD>
<DD>A single vector map can be connected to multiple database tables. This number determines which table to use.</DD>
<DD>Default: <em>1</em></DD>
<DT><b>output</b>=<em>name</em></DT>
<DD>Name for output vector map</DD>
<DT><b>operator</b>=<em>string</em></DT>
<DD>Operator defines required relation between features. A feature is written to output if the result of operation 'ainput operator binput' is true. An input feature is considered to be true, if category of given layer is defined.<br> overlap: features partially or completely overlap</DD>
<DD>Options: <em>overlap</em></DD>
<DD>Default: <em>overlap</em></DD>
</DL>
<h2>DESCRIPTION</h2>
<em>v.select</em> allows the user to select features from a vector
by features from another one.
<h2>NOTES</h2>
<h2>EXAMPLES</h2>
Extract forest fire points from larger fire map:
<div class="code"><pre>
v.select ainput=fire binput=forest output=forest_fire
</pre></div>
<P>
Extract Italian rivers from VMAP0 watercourses map:
<div class="code"><pre>
v.select ain=watrcrsl_eurnasia_wgs84 bin=italy_area \
out=watrcrsl_italy op=overlap
</pre></div>
<h2>SEE ALSO</h2>
<em>
<a HREF="v.overlay.html">v.overlay</a>,
<a HREF="sql.html">GRASS SQL interface</a></em>
<h2>AUTHORS</h2>
Radim Blazek
<p><i>Last changed: $Date: 2007-03-22 09:00:33 +0100 (Thu, 22 Mar 2007) $</i>
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