[postgis-users] OpenStreetMap + osm2pgsql + pgRouting into Postgis

[Maria Arias de Reyna]

El Wednesday 19 May 2010, roshni.spain escribió:
> Hi,
> how can i be sure about this? If i get wrong results i mean ...

Well, you can try some samples and check it by hand.

If I am not mistaken, that number is used to know the size of the buffer used 
to calculate which node goes to each vertex. 

If you use a small number and the lines you are using are not close enough, 
pgrouting will think they are not touching and will not assign them the same 
vertex.

If you use a big number, pgrouting can think that lines, who should not be 
touching, are touching. Then it can lead you to stupid routes, like jumping 
from one road to the paralell.

-- 
María Arias de Reyna Domínguez
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Emergya Consultoría 
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