[pgrouting-users] Wrong results at routing by choosing wrong start/end points?

[Kai Behncke]

Hi Marco,

> regarding to http://pgrouting.postlbs.org/wiki/killing_some_bugs
> 
> by calculating the Route twice by changing start and endpoint ist a 
> possibility to fix the problem in the triangle-like way at the 
> screenshot. But does this also work if the points are many crossings 
> away? Dont' I have to compare four results?:
> 
> SELECT gid, the_geom FROM dijkstra_sp_delta(
>      '".TABLE."', ".$startEdge['source'].", ".$endEdge['target'].", 3000)
> 
> SELECT gid, the_geom FROM dijkstra_sp_delta(
>      '".TABLE."', ".$endEdge['source'].", ".$startEdge['target'].", 3000)
> 
> SELECT gid, the_geom FROM dijkstra_sp_delta(
>      '".TABLE."', ".$startEdge['source'].", ".$startEdge['target'].",
> 3000)
> 
> SELECT gid, the_geom FROM dijkstra_sp_delta(
>      '".TABLE."', ".$endEdge['source'].", ".$endEdge['target'].", 3000)







...when I created the tutorial I was wondering exactly the same but I 
think it can`t be 

SELECT gid, the_geom FROM dijkstra_sp_delta(
      '".TABLE."', ".$startEdge['source'].", ".$startEdge['target'].",
 3000)

or 

 SELECT gid, the_geom FROM dijkstra_sp_delta(
      '".TABLE."', ".$endEdge['source'].", ".$endEdge['target'].", 3000)


because then the route calculation is only on one edge (and not between the needed two edges).

Best regards, Kai


So far it runs on 
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