Yes and no. What I am really after is an algorithm that returns me all paths 
connecting two given nodes up to a certain path length as I want to then 
analyse this result set further to analyse how "efficient" a given path is. 

For me there is some correlation between path length and efficiency, however, 
the shortest path may not necessarily  be the most efficient path so I need to 
define the result set that I feed into my analysis slightly wider than just the 
list of shortest paths. In this case I may be interested in e.g. all paths of 
length 3, 4, and 5. 

I realise that returning all paths connecting two nodes may lead to 
combinatorial explosion in some cases but is it possible to get graph-tool to 
return all paths up to a certain length?

Thank you for pointing me towards that documentation entry - I should indeed 
clearly have read it more carefully.

Best wishes,

Philipp

-----Original Message-----
From: graph-tool [mailto:[email protected]] On Behalf Of Tiago de 
Paula Peixoto
Sent: 09 March 2016 22:13
To: [email protected]
Subject: Re: [graph-tool] How is all_shortest_paths defined?

On 09.03.2016 22:58, Philipp-Maximilian Jacob wrote:
> The known path is three steps long (i.e. contains four vertices) while 
> the paths returned by all_shortest_paths are only two steps long. Is 
> there any way of extending the cut off criterion for 
> all_shortest_paths so that it would return the known path too?

So, you want a function that returns all shortest paths to return a path that 
is not the shortest one?

There is no "cut off criterion"... The algorithm finds the shortest paths, 
which in this case are paths of length two.

> It seems to me as if graph.edge(u,v) only returns one edge when 
> called.

Please take a more careful look at the documentation:

   https://graph-tool.skewed.de/static/doc/graph_tool.html#graph_tool.Graph.edge

Note what it says about the "all_edges" argument:

    "If all_edges=True then a list is returned with all the parallel
    edges from s to t, otherwise only one edge is returned."

Best,
Tiago

--
Tiago de Paula Peixoto <[email protected]>


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