<br><br><div class="gmail_quote">2011/1/14 Emre Koc <span dir="ltr"><<a href="mailto:emrekoch@gmail.com">emrekoch@gmail.com</a>></span><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<font size="2"><font face="tahoma,sans-serif"><br clear="all"></font></font>/emre<br>
<br><br><div class="gmail_quote"><div class="im">On Fri, Jan 14, 2011 at 10:15 AM, Daniel Kastl <span dir="ltr"><<a href="mailto:daniel@georepublic.de" target="_blank">daniel@georepublic.de</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<br><br><div class="gmail_quote">2011/1/14 Emre Koc <span dir="ltr"><<a href="mailto:emrekoch@gmail.com" target="_blank">emrekoch@gmail.com</a>></span><div><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<font size="2"><font face="tahoma,sans-serif">Sure</font></font><div><font size="2"><font face="tahoma,sans-serif"><br></font></font></div><div><font size="2"><font face="tahoma,sans-serif">Here is my sql query for that image.</font></font></div>
<div><font size="2"><font face="tahoma,sans-serif"><br></font></font></div><div><font size="2"><font face="tahoma,sans-serif"><div>SELECT edges.gid, ST_AsText(edges.the_geom) AS geotext, </div><div> edges.ft_minutes,</div>
<div><span style="white-space:pre-wrap"> </span>edges.meters</div><div><span style="white-space:pre-wrap"> </span>FROM edges,</div><div><span style="white-space:pre-wrap"> </span>(SELECT edge_id, cost FROM driving_distance('SELECT gid as id,</div>
<div><span style="white-space:pre-wrap"> </span> source::integer,</div><div><span style="white-space:pre-wrap"> </span> target::integer,</div><div><span style="white-space:pre-wrap"> </span> meters::double precision as cost</div>
<div><span style="white-space:pre-wrap"> </span>FROM edges', $startVertexID, $cost,false,false)</div><div><span style="white-space:pre-wrap"> </span>) as rt </div><div><span style="white-space:pre-wrap"> </span>WHERE edges.gid=rt.edge_id;";</div>
<div><br></div><div>I just give a sample vertex id and a cost value in meters and got resulting edges. Normally when I find shortest paths all roads are connected so the graph is ok. But this driving directions does not output connected roads, thats the thing I do not understand. </div>
</font></font></div></blockquote><div><br></div></div><div>Driving distance returns you all the vertices you can reach from a start point to within what you have defined as the maximum costs.</div><div>I think you're looking for another query (Dijkstra, A-Star, Shooting Star).</div>
</div></blockquote><div><br></div></div><div>I am looking for a output that shows road network that I can reach from a start point within a defined maximum cost. So if driving distance does not output connected edges what do you suggest me to do in order to have a connected road network with the given vertices ? Running shortest path for each vertex does not seem feasible but I am unable to see a way to implement it without going inside c functions. </div>
<div class="im">
<div><br></div></div></div></blockquote><div><br></div><div>Sorry, I was wrong ... it's the right function you're using. Somehow read driving directions somewhere before.</div><div>Driving directions does what you need, except that it returns you a list of vertices you can reach and the edges column doesn't return anything useful.</div>
<div><br></div><div>This custom wrapper function takes the vertices and calculates a polygon that contains all of them:</div><div><meta http-equiv="content-type" content="text/html; charset=utf-8"><a href="https://github.com/pgRouting/pgrouting/blob/master/extra/driving_distance/sql/routing_dd_wrappers.sql#L78">https://github.com/pgRouting/pgrouting/blob/master/extra/driving_distance/sql/routing_dd_wrappers.sql#L78</a></div>
<div><br></div><div>Daniel</div><div><br></div><div><br></div><div><br></div><div><br></div><div> </div></div><br>-- <br><span style="font-family:arial, sans-serif;font-size:13px;border-collapse:collapse">Georepublic UG & Georepublic Japan<br>
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