<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><div>Hi Geoff,</div><div><br></div><div>I am also new to this, but have been experimenting with the same sort of problem. </div><div><br></div><div>My workings and particularly the "my_get_network_catchment.sql" function which I have uploaded to <a href="https://github.com/alaw005/pgrouting_functions">https://github.com/alaw005/pgrouting_functions</a> might be helpful. The solution was to use a loop within a postgis function. <br>
</div><div><br></div><div>Regards</div><div>Adam</div><div><br></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">

Date: Fri, 29 Aug 2014 10:41:19 -0400<br>
From: "Dougherty, Geoff" <<a href="mailto:geoffdougherty@gmail.com">geoffdougherty@gmail.com</a>><br>
To: <a href="mailto:pgrouting-users@lists.osgeo.org">pgrouting-users@lists.osgeo.org</a><br>
Subject: [pgrouting-users] driving distance for multiple nodes<br>
Message-ID: <<a href="mailto:705E7660-B5D6-4848-BD8A-30692DBBEBCF@gmail.com">705E7660-B5D6-4848-BD8A-30692DBBEBCF@gmail.com</a>><br>
Content-Type: text/plain; charset="windows-1252"<br>
<br>
Hi, all.<br>
<br>
I?m new to postGis/pgRouting, and am trying to find driving distances to all nodes within a certain distance of a set of starting points/nodes.<br>
<br>
I have some code  (thanks to <a href="http://anitagraser.com/2011/05/13/catchment-areas-with-pgrouting-driving_distance/" target="_blank">http://anitagraser.com/2011/05/13/catchment-areas-with-pgrouting-driving_distance/</a>) that seems to work for a single point:<br>

<br>
SELECT seq, id1 AS node, cost<br>
        FROM pgr_drivingDistance(<br>
                'SELECT gid as id, source, target, length::float8 AS cost FROM roads',<br>
                7, 100000, false, false<br>
        );<br>
<br>
However, I have a separate table containing a few hundred points (with lat, lon and geom)  for which I need to identify driving distance to other points. Do I need to consider adding some additional join, or perhaps some python code to loop through the other table?<br>
<br>
</blockquote></div><br></div></div>