[pgrouting-users] Build the "right" direction in a network, from a fixed starting point

[andy]

I must correct myself: I’m NOT able to read in the data that 3 is not
reachable from 1.

Thank you

Il gio 17 mag 2018, 23:57 andy <aborruso at gmail.com> ha scritto:

> Hi Vicky,
>
> On Thu, 17 May 2018 at 20:22, Vicky Vergara vicky at georepublic.de
> <http://mailto:vicky@georepublic.de> wrote:
>
>
>> I suggest that you follow the workshop,
>> https://workshop.pgrouting.org/2.4.11/en/index.html
>> and/or use the sample data of the documentation and do the examples on
>> the documentation (there is a "tutorial" in the documentation, maybe out of
>> date, but gives an idea)
>>
>> Thank you.
>
>
>> The straight answer to your question is yes, you need a cost (&
>> reverse_cost is optional)
>>
> Now I have a route with a cost:
> seq path_seq end_vid node edge cost agg_cost
> 1 1 2 1 1 1875.887941 0.0
> 2 2 2 2 -1 0.0 1875.887941
> 3 1 3 1 2 1551.56248159 0.0
> 4 2 3 3 -1 0.0 1551.56248159
> 5 1 4 1 3 1506.74402482 0.0
> 6 2 4 4 -1 0.0 1506.74402482
> 7 1 5 1 3 1506.74402482 0.0
> 8 2 5 4 4 1208.08883443 1506.74402482
> 9 3 5 5 -1 0.0 2714.83285924
> 10 1 6 1 1 1875.887941 0.0
> 11 2 6 2 5 1447.12212188 1875.887941
> 12 3 6 6 -1 0.0 3323.01006288
>
> The command I have used:
>
> SELECT * FROM pgr_dijkstra('SELECT ogc_fid as id, source, target, st_length(wkb_geometry)
>                            as "cost" FROM linee',1,ARRAY[2,3,4,5,6])
>
> The starting point is 1, but I’m able to read in the data that 3 is not
> reachable from 1.
>
> What’s wrong in my reasoning ?
>
> Thank you
>
> [image: immagine.png]
>
> ​
> --
> ___________________
>
> Andrea Borruso
> website: https://medium.com/tantotanto
> 38° 7' 48" N, 13° 21' 9" E, EPSG:4326
> ___________________
>
> "cercare e saper riconoscere chi e cosa,
>  in mezzo all’inferno, non è inferno,
> e farlo durare, e dargli spazio"
>
> Italo Calvino
>
-- 

______
Scusami per la brevità, ti sto scrivendo dal cellulare.

website: https://medium.com/tantotanto
38° 7' 48" N, 13° 21' 9" E EPSG:4326
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/pgrouting-users/attachments/20180518/c03a5880/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: immagine.png
Type: image/png
Size: 18287 bytes
Desc: not available
URL: <http://lists.osgeo.org/pipermail/pgrouting-users/attachments/20180518/c03a5880/attachment-0001.png>