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<h2>NAME</h2>
<em><b>v.net</b></em> - Network maintenance.
<h2>KEYWORDS</h2>
vector, networking
<h2>SYNOPSIS</h2>
<b>v.net</b><br>
<b>v.net help</b><br>
<b>v.net</b> [-<b>c</b>] <b>input</b>=<em>name</em> [<b>points</b>=<em>name</em>] [<b>output</b>=<em>name</em>] [<b>operation</b>=<em>string</em>] [<b>alayer</b>=<em>integer</em>] [<b>nlayer</b>=<em>integer</em>] [<b>thresh</b>=<em>float</em>] [--<b>overwrite</b>] [--<b>verbose</b>] [--<b>quiet</b>]
<h3>Flags:</h3>
<DL>
<DT><b>-c</b></DT>
<DD>Assign unique categories to new points</DD>
<DD>For operation 'nodes'</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>input</b>=<em>name</em></DT>
<DD>Name of input vector map</DD>
<DT><b>points</b>=<em>name</em></DT>
<DD>Name of input point vector map</DD>
<DD>Required for operation 'connect'</DD>
<DT><b>output</b>=<em>name</em></DT>
<DD>Name for output vector map</DD>
<DT><b>operation</b>=<em>string</em></DT>
<DD>Operation to be performed</DD>
<DD>Options: <em>nodes,connect,report,nreport</em></DD>
<DD>Default: <em>nodes</em></DD>
<DD><b>nodes</b>: new point is placed on each node (line end) if doesn't exist</DD>
<DD><b>connect</b>: connect still unconnected points to vector network by inserting new line(s)</DD>
<DD><b>report</b>: print to standard output {line_category start_point_category end_point_category}</DD>
<DD><b>nreport</b>: print to standard output {point_category line_category[,line_category...]}</DD>
<DT><b>alayer</b>=<em>integer</em></DT>
<DD>Arc layer (network)</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>nlayer</b>=<em>integer</em></DT>
<DD>Node layer (points)</DD>
<DD>A single vector map can be connected to multiple database tables. This number determines which table to use.</DD>
<DD>Default: <em>2</em></DD>
<DT><b>thresh</b>=<em>float</em></DT>
<DD>Threshold</DD>
<DD>Required for operation 'connect'. Connect points in given threshold.</DD>
</DL>
<h2>DESCRIPTION</h2>
<em>v.net</em> is used for vector network maps maintenance.
It reports about the current network graph status.
It also permits to globally insert missing nodes and to connect
unconnected nodes to the graph within a given distance threshold.
<h3>NOTES</h3>
If vector editing is required to modify the graph, <em>v.digit</em>
or <em>v.edit</em> can be used. Separately,
<a HREF="lrs.html">Linear Referencing System</a> is available
in GRASS.
<h3>EXAMPLES</h3>
Spearfish based examples:<P>
Create nodes globally for all line ends and intersections:
<br>
<div class="code"><pre>
v.net in=streams out=streams_node
</pre></div>
<P>
Merge in nodes from a separate map within given threshold:
<br>
<div class="code"><pre>
echo "1|601653.5|4922869.2|start
2|593330.8|4924096.6|end" | v.in.ascii cat=1 x=2 y=3 out=startend col="cat integer, \
east double precision, north double precision, label varchar(43)"
#create lines map connecting points to network (on layer 2)
v.net myroads points=startend out=myroads_net op=connect thresh=200
</pre></div>
<h2>SEE ALSO</h2>
<em><a HREF="v.digit.html">v.digit</a></em>,
<em><a HREF="v.edit.html">v.edit</a></em>,
<em><a HREF="v.net.iso.html">v.net.iso</a></em>,
<em><a HREF="v.net.path.html">v.net.path</a></em>,
<em><a HREF="v.net.steiner.html">v.net.steiner</a></em>,
<em><a HREF="v.net.salesman.html">v.net.salesman</a></em>
<h2>AUTHORS</h2>
Radim Blazek, ITC-Irst, Trento, Italy<BR>
Martin Landa, FBK-Irst, Trento, Italy
<p><i>Last changed: $Date: 2007-12-17 14:45:01 +0100 (Mon, 17 Dec 2007) $</i>
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