<div dir="ltr"><div class="gmail_default" style="font-family:monospace,monospace">+1 for using pgRouting as a graph tools rather than traffic tool<br></div><div class="gmail_default" style="font-family:monospace,monospace">Cheers,<br></div><div class="gmail_default" style="font-family:monospace,monospace">Rémi-C<br></div></div><div class="gmail_extra"><br><div class="gmail_quote">2016-03-24 16:07 GMT+01:00 Stephen Woodbridge <span dir="ltr"><<a href="mailto:woodbri@swoodbridge.com" target="_blank">woodbri@swoodbridge.com</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi Dave,<br>
<br>
I just looked at the wikipedia pages and these analysis look very interesting. My primary focus is on vehicle routing so I'm not sure I'm a good judge of their usefulness, but pgRouting has been used for Max Flow Analysis and other not vehicle routing problems.<br>
<br>
I've cc'd this to the user list to get a wider audience and see if there is interest from other users in this kind of analysis.<br>
<br>
Also if you put these in a github repository, I believe we have a page in our wiki that points to other projects that might be useful to pgRouting users. See Friends of pgRouting:<br>
<a href="https://github.com/pgRouting/pgrouting/wiki#friends-of-pgrouting" rel="noreferrer" target="_blank">https://github.com/pgRouting/pgrouting/wiki#friends-of-pgrouting</a><br>
<br>
-Steve<br>
<br>
On 3/24/2016 10:51 AM, Stephen Woodbridge wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<br>
<br>
<br>
-------- Forwarded Message --------<br>
Subject: Fwd: [pgrouting-dev] an implementation of beta skeletons,<br>
relative neighborhood graph and gabriel graphs<br>
Date: Tue, 22 Mar 2016 09:21:44 +0000<br>
From: <a href="mailto:dave.potts@pinan.co.uk" target="_blank">dave.potts@pinan.co.uk</a><br>
To: <a href="mailto:woodbri@swoodbridge.com" target="_blank">woodbri@swoodbridge.com</a><br>
<br>
<br>
<br>
Hi Steve,<br>
<br>
Sorry to trouble you.<br>
<br>
I email this to the development email list and did not get a response.<br>
<br>
I know that Beta skelton graphs are not a standard routing style<br>
function but its the sort otf thing I use in my research which is all<br>
about network anaylsis. I just wondered if anybody else did.<br>
<br>
Dave.<br>
<br>
-------- Forwarded message -------<br>
From: <a href="mailto:dave.potts@pinan.co.uk" target="_blank">dave.potts@pinan.co.uk</a> <mailto:<a href="mailto:dave.potts@pinan.co.uk" target="_blank">dave.potts@pinan.co.uk</a>><br>
To: <a href="mailto:pgrouting-dev@lists.osgeo.org" target="_blank">pgrouting-dev@lists.osgeo.org</a> <mailto:<a href="mailto:pgrouting-dev@lists.osgeo.org" target="_blank">pgrouting-dev@lists.osgeo.org</a>><br>
Sent: 19 March 2016 17:28<br>
Subject: [pgrouting-dev] an implementation of beta skeletons, relative<br>
neighborhood graph and gabriel graphs<br>
Is there any interest in any off the above graph forms in the routing<br>
library?<br>
<br>
See<br>
<a href="https://en.wikipedia.org/wiki/Beta_skeleton" rel="noreferrer" target="_blank">https://en.wikipedia.org/wiki/Beta_skeleton</a><br>
<a href="https://en.wikipedia.org/wiki/Relative_neighborhood_graph" rel="noreferrer" target="_blank">https://en.wikipedia.org/wiki/Relative_neighborhood_graph</a><br>
<a href="https://en.wikipedia.org/wiki/Gabriel_graph" rel="noreferrer" target="_blank">https://en.wikipedia.org/wiki/Gabriel_graph</a><br>
<br>
I have implementation with the following method signatures<br>
<br>
CREATE OR REPLACE FUNCTION pgr_beta_skelton(sql text, beta float,OUT id<br>
integer ,OUT id1 integer , OUT id2 integer)<br>
RETURNS SETOF RECORD AS<br>
'$libdir/librouting-2.1', 'dir_graph_beta_skelton'<br>
LANGUAGE c STABLE STRICT;<br>
<br>
CREATE OR REPLACE FUNCTION pgr_relative_neigborhood_graph(sql text ,OUT<br>
id integer ,OUT id1 integer , OUT id2 integer)<br>
RETURNS SETOF RECORD AS<br>
'$libdir/librouting-2.1', 'dir_graph_relative_neigborhood_graph'<br>
LANGUAGE c STABLE STRICT;<br>
<br>
CREATE OR REPLACE FUNCTION pgr_gabriel_graph(sql text ,OUT id integer<br>
,OUT id1 integer , OUT id2 integer)<br>
RETURNS SETOF RECORD AS<br>
'$libdir/librouting-2.1', 'dir_graph_gabriel_graph'<br>
LANGUAGE c STABLE STRICT;<br>
<br>
They all take an sql statement of the form<br>
<br>
select st_makeline(v1.the_geom,v2.the_geom) as the_geom from<br>
pgr_gabriel_graph('select id,st_x(the_geom) as x ,st_y(the_geom) as y<br>
from tmp_table2'), tmp_table2 v1, tmp_table2 v2 where id1=<a href="http://v1.id" rel="noreferrer" target="_blank">v1.id</a> and<br>
id2=<a href="http://v2.id" rel="noreferrer" target="_blank">v2.id</a>;<br>
<br>
Ie the expect an set of objects with an id and a x and y coordinate<br>
<br>
In this example tmp_table functions as resource of data, and the above<br>
statement returns a serries of id statements id refers to id of 1st x/y<br>
node and the 2nd id refers to 2md x/y pair<br>
eg<br>
id | id1 | id2<br>
-----+-----+-----<br>
1 | 607 | 558<br>
2 | 606 | 542<br>
3 | 605 | 594<br>
4 | 605 | 520<br>
5 | 604 | 579<br>
6 | 604 | 525<br>
7 | 603 | 605<br>
8 | 603 | 594<br>
9 | 603 | 530<br>
10 | 602 | 580<br>
11 | 602 | 563<br>
12 | 601 | 537<br>
13 | 601 | 534<br>
14 | 600 | 523<br>
15 | 599 | 601<br>
16 | 599 | 522<br>
17 | 598 | 590<br>
<br>
<br>
regards<br>
<br>
Dave.<br>
<br>
<br>
<br>
<br>
<br>
---<br>
This email has been checked for viruses by Avast antivirus software.<br>
<a href="https://www.avast.com/antivirus" rel="noreferrer" target="_blank">https://www.avast.com/antivirus</a><br>
<br>
_______________________________________________<br>
pgrouting-dev mailing list<br>
<a href="mailto:pgrouting-dev@lists.osgeo.org" target="_blank">pgrouting-dev@lists.osgeo.org</a><br>
<a href="http://lists.osgeo.org/mailman/listinfo/pgrouting-dev" rel="noreferrer" target="_blank">http://lists.osgeo.org/mailman/listinfo/pgrouting-dev</a><br>
</blockquote>
<br>
<br>
---<br>
This email has been checked for viruses by Avast antivirus software.<br>
<a href="https://www.avast.com/antivirus" rel="noreferrer" target="_blank">https://www.avast.com/antivirus</a><br>
<br>
_______________________________________________<br>
Pgrouting-users mailing list<br>
<a href="mailto:Pgrouting-users@lists.osgeo.org" target="_blank">Pgrouting-users@lists.osgeo.org</a><br>
<a href="http://lists.osgeo.org/mailman/listinfo/pgrouting-users" rel="noreferrer" target="_blank">http://lists.osgeo.org/mailman/listinfo/pgrouting-users</a></blockquote></div><br></div>