Geografic-Information-System/display/d.path/d.path.html

<h2>DESCRIPTION</h2>

<em>d.path</em> enables shortest path vector networking.
Costs may be either line lengths, or attributes saved in a database table.
Supported are cost assignments for both arcs and nodes, and also different
in both directions of a vector line. For areas cost will be calculated along
boundary lines. 

<h2>NOTE</h2>

The user needs to display a vector map before using d.path. The 'from' and 'to'
points are entered by mouse into the map displayed in the GRASS monitor, or
if the <b>coor</b> option is used they can be specified non-interactively.
The actions bound to the mouse buttons are described in the terminal
window when running the command.
<P>
To calculate shortest path non-interactively and save the path to a new vector
map, use the <em>v.net.path</em> module.

<h2>EXAMPLE</h2>

Interactive shortest path routing on road network (Spearfish region):
<div class="code"><pre>
g.region vector=roads
d.vect roads
d.path roads
</pre></div>

Non-interactive shortest path routing on road network (Spearfish region):
<div class="code"><pre>
d.path -b roads coor=601653.5,4922869.2,593330.8,4924096.6
</pre></div>

<h2>SEE ALSO</h2>

<em>
<a HREF="v.net.path.html">v.net.path</a>
</em>

<h2>AUTHOR</h2>

Radim Blazek, ITC-Irst, Trento, Italy

<p>
<i>Last changed: $Date$</i>