<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<div class="moz-cite-prefix">Hi Quinton,<br>
<br>
looks like mailman didn't let it through ... but google + the
"cache link" helped me already ;)<br>
<br>
Also: are you finally receiving mails from this list or are you
reading it via nabble or similar?<br>
<br>
Regards,<br>
Peter.<br>
<br>
</div>
<blockquote
cite="mid:8291675D-4013-41C1-9121-3AD7BA31FE2A@gmail.com"
type="cite">
<meta http-equiv="content-type" content="text/html;
charset=ISO-8859-1">
<div>Are you happy I attach it to a mail response here? It is
focused on the public transport problem.<br>
<br>
Sent from my iPhone</div>
<div><br>
On 17/04/2013, at 18:08, Peter K <<a moz-do-not-send="true"
href="mailto:peathal@yahoo.de">peathal@yahoo.de</a>> wrote:<br>
<br>
</div>
<blockquote type="cite">
<div>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
<div class="moz-cite-prefix">Hi Quinton,<br>
<br>
thanks for pointing us to this paper (looks like <a
moz-do-not-send="true" href="http://uni-freiburg.de">uni-freiburg.de</a>
is down -> "Fast routing in very large public
transportation networks using transfer patterns")<br>
<div align="left">Also the RAPTOR paper I mentioned earlier
had some suggestions regarding efficient storage of routes
etc in the appendix <a moz-do-not-send="true"
href="http://research.microsoft.com/apps/pubs/default.aspx?id=156567">"Round-Based
Public Transit Routing"</a><br>
</div>
<br>
Regards,<br>
Peter.<br>
<br>
<br>
</div>
<blockquote
cite="mid:485EA734-503B-453A-8767-7F319762286B@gmail.com"
type="cite">Hi Guys,
<div><br>
</div>
<div>On this topic, I assume you have seen the paper on
Transfer Patterns. It does give some nice suggestions on
the types of nodes and arcs to use for these purpose: <a
moz-do-not-send="true"
href="http://ad.informatik.uni-freiburg.de/files/transferpatterns.pdf">http://ad.informatik.uni-freiburg.de/files/transferpatterns.pdf</a></div>
<div><br>
</div>
<div>Regards,</div>
<div>Quinton Anderson</div>
<div><br>
<div>
<div>On 17 Apr 2013, at 1:38 AM, Peter K wrote:</div>
<br class="Apple-interchange-newline">
<blockquote type="cite">
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
<div bgcolor="#FFFFFF" text="#000000">
<div class="moz-cite-prefix">Hi Thomas,<br>
<br>
regarding the size of the graph I don't expect
problems, as the world wide OSM graph currently
has over 83mio nodes.<br>
<br>
The problem is the algorithm and if it scales.
E.g. if I would use a normal bidirectional
dijkstra for a 10 000km query it would take over
10 seconds but with a short cutting or
hierarchical algorithm like contraction
hierarchies it is under 100ms! So I'm really
excited to hear what you choose for an algorithm
:) !<br>
<br>
Regards,<br>
Peter.<br>
<br>
</div>
<blockquote
cite="mid:516D5004.9020304@student.ethz.ch"
type="cite">
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
<div class="moz-cite-prefix">Thank you for your
response and offering your help.<br>
<br>
I have looked little bit into the thematic and
it seems that a implementation with a
time-expended graph would be very straight
forward. So, I would have to implement a
GTFSReader which creates the public transport
graph.<br>
Would this approach perform well with ~1 million
nodes (time stops)?<br>
<br>
Regards,<br>
Thomas<br>
<br>
<br>
<br>
On 04/08/2013 09:09 PM, Peter K wrote:<br>
</div>
<blockquote cite="mid:51631606.7070708@yahoo.de"
type="cite">
<meta http-equiv="Content-Type"
content="text/html; charset=ISO-8859-1">
Hi Thomas,<br>
<br>
public transport would be nice to have, yes :) <br>
<br>
But there is no time dependent datastructure
yet, and the algorithms are not tuned regarding
public transport. So, it is not easy to
implement. If you do not have much data you can
just use the GraphStorage (and model the time
via nodes), then use a-star or dijkstra to get
routes. One minor gimmick would be the
'wayGeometry' (in EdgeIterator) which you could
use to display the real paths between two nodes
of the trains/buses/... instead of straight line
like e.g. google does. <br>
<br>
To properly implement public transport one would
probably need to create a new Graph interface
and iterate from that, e.g. create a simple
algorithm and then use more advanced like
RAPTOR. Also a new GTFSReader will be necessary
instead of or combined with OSMReader. <br>
<br>
If you're trying something you can be sure to
have my assistance :) ! <br>
<br>
Regards, <br>
Peter.<br>
<br>
------------------------------------------------------------<br>
<br>
Hello, <br>
<br>
I'm considering to use graphhopper for a student
project. But for that I <br>
also need support for public transport. So I'm
thinking about <br>
implementing it my own... <br>
Do you have any thoughts or plans how to
implement it and would it be a <br>
lot of work? <br>
<br>
Regards, <br>
Thomas </blockquote>
</blockquote>
</div>
</blockquote>
</div>
</div>
</blockquote>
</div>
</blockquote>
<blockquote type="cite">
<div><span>_______________________________________________</span><br>
<span>GraphHopper mailing list</span><br>
<span><a moz-do-not-send="true"
href="mailto:GraphHopper@openstreetmap.org">GraphHopper@openstreetmap.org</a></span><br>
<span><a moz-do-not-send="true"
href="http://lists.openstreetmap.org/listinfo/graphhopper">http://lists.openstreetmap.org/listinfo/graphhopper</a></span><br>
</div>
</blockquote>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
GraphHopper mailing list
<a class="moz-txt-link-abbreviated" href="mailto:GraphHopper@openstreetmap.org">GraphHopper@openstreetmap.org</a>
<a class="moz-txt-link-freetext" href="http://lists.openstreetmap.org/listinfo/graphhopper">http://lists.openstreetmap.org/listinfo/graphhopper</a>
</pre>
</blockquote>
<br>
<br>
<pre class="moz-signature" cols="72">--
GraphHopper.com Your way is our destination!</pre>
</body>
</html>