[pgrouting-dev] APSP Floyd-Warshall missing results

[Stephen Woodbridge]

Hi Hervé,

I'm not sure I can be more help that Daniel was. I merged the GSoC code 
into the release and wrote the test cases, but beyond that you would 
have to check with the original authors. If you have more information 
that would useful in debugging this issue, I have reopened #106 also 
note #105.

Is upstream cost negative cost values?
I suspect that negative costs are not support and just cause the edge to 
be removed for that direction.

-Steve

On 11/7/2013 12:14 PM, Hervé Pella wrote:
>
> I saw in "https://github.com/pgRouting/pgrouting/issues/107" the
> discussion about the shortest path pairs method :
>
> "It seems that APSP Floyd-Warshall does not return all shortest path
> pairs, at least not with the documentation example:
> http://docs.pgrouting.org/dev/src/apsp_warshall/doc/index.html
>
> It also returns a different number of results than APSP Johnson
> algorithm, which has a similar issue #106."
>
> I work on hydrographic network  and more specifically on connectivity
> between different fish habitat. I try to calculate the distance
> between arcs through the network (both downstream direction but also
> upstream). I tested the two methods for calculate this metrics : APSP
> Johnson APSP Floyd-Warshall (also with the reverse_cost) from
> pgrouting 2.0 , postgis 2.1 and postgres 9.3.
>
> They give me the same results and do not go back in networks. They
> only calculate distance to downstream without going upstream in the
> network. Do you have more information about this problem ? Do you
> know someone in the PgRouting community who would work on this issue
> ?
>
> Best regards
>
> Hervé Pella Irstea Lyon - France
>