[pgrouting-dev] Having problems under standing the distance matrix of TSP in respect to route network pgroute version 2
Dave Potts
dave.potts at pinan.co.uk
Thu Jun 13 22:17:42 PDT 2013
On 14/06/13 02:59, Daniel Kastl wrote:
Hi Daniel, List
I must admit I found the entire process of creating a postgress array in
a suitable form for the pgr_tsp function to be a exercise in slow torture!
Would anybody have any major objections if I attempted to rewrite the
interface so it took a normal sql querry?
Something like
pgr_costResult[]pgr_tsp('SELECT source,target distance FROM vertex_table',2);
That way the problem with creating a square array in postgres would disappear.
Dave
<https://www.google.nl/search?client=ubuntu&hs=uQi&channel=fs&gl=uk&q=exercise+in+slow+torture&spell=1&sa=X&ei=BKa6UYnAF5G20QXc_4HQCg&ved=0CCcQvwUoAA>
> Hi Dave,
>
> Thanks for reporting. Maybe I just mixed up something with copy & paste.
> I remember that I needed to add a vertex table to the sample data for
> the new TSP with distance matrix and got the ID's a bit wrong first.
> Will take a look.
>
> Daniel
>
>
> On Fri, Jun 14, 2013 at 7:40 AM, Stephen Woodbridge
> <woodbri at swoodbridge.com <mailto:woodbri at swoodbridge.com>> wrote:
>
> Dave - moving this over to the pgrouting list.
>
>
> Hi Dave,
>
> I'm not sure the Daniel used the example data network for this
> example. The data looks like one of the matrix I used in my test
> cases.
>
> src/tsp/test/*.test
>
> I just made up numbers for a symmetric matrix. It was not taken
> from an actual network.
>
> So the sly part is that its NOT from a graph ;)
>
> Daniel - please correct me it you did something else.
>
> -Steve
>
> On 6/13/2013 6:11 PM, Dave Potts wrote:
>
>
> In the travel sales person problem an example is provided, I
> having
> problems understanding it
>
> The example route network is posted as
> http://docs.pgrouting.org/dev/doc/src/developer/sampledata.html#sampledata
>
> I have assume the distance between red node 1 and red node 3
> is 2, ie
> the unit distance 1 +1 which I make to be 2
>
> given that
>
> I think the route matrix should be
>
> 1 2 3 4
> ======
> 1 | 0 1 2 3
> 2 | 1 0 1 2
> 3 | 2 1 0 1
> 4 | 3 2 1 0
>
> distance 1 to 4 is 1+1 +1 ==3
> distance 2 to 4 is 1+1 ==2
> distance 3 to 4 is 1
> etc
>
> But the give value is (please see
> http://docs.pgrouting.org/dev/src/tsp/doc/index.html)
> 1 2 3 4
>
> 1 {0,1,2,3},
> 2 {1,0,3,2},
> 3 {2,3,0,4},
> 4 {3,2,4,0}
>
> I just don't understand how the distance between 3 and 4 can
> be the
> value 4, ditto he values between 2 and 3
>
> Have I missed something sly ?
>
> Dave.
>
>
>
> _______________________________________________
> postgis-devel mailing list
> postgis-devel at lists.osgeo.org
> <mailto:postgis-devel at lists.osgeo.org>
> http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-devel
>
>
> _______________________________________________
> postgis-devel mailing list
> postgis-devel at lists.osgeo.org <mailto:postgis-devel at lists.osgeo.org>
> http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-devel
> _______________________________________________
> pgrouting-dev mailing list
> pgrouting-dev at lists.osgeo.org <mailto:pgrouting-dev at lists.osgeo.org>
> http://lists.osgeo.org/mailman/listinfo/pgrouting-dev
>
>
>
>
> --
> Georepublic UG & Georepublic Japan
> eMail: daniel.kastl at georepublic.de <mailto:daniel.kastl at georepublic.de>
> Web: http://georepublic.de <http://georepublic.de/>
>
>
> _______________________________________________
> pgrouting-dev mailing list
> pgrouting-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/pgrouting-dev
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/pgrouting-dev/attachments/20130614/9f7fc347/attachment.html>
More information about the pgrouting-dev
mailing list