Re: [jgrapht-users] JGraphT Enquiry: KShortestPaths Bug?

[John S. <js...@gm...>]

Hi,

Please send messages such as this to the jgrapht-users lists (not me
personally).

If you submit an isolated JUnit test case demonstrating the problem,
there's a better chance of someone being able to help with it.

JVS

On Mon, Jun 18, 2012 at 2:13 AM, Genliang Guan
<gen...@sy...> wrote:
> Dear John,
>
> This is Ron Guan, studying at School of IT, University of Sydney.
>
> I am using the fantastic JGraphT library, or more specifically the
> KShortestPaths, to implement the algorithm proposed at "Multi-Sentence
> Compression: Finding Shortest Paths inWord Graphs"
>  (http://dejanseo.com.au/research/google/36338.pdf). You may just look at
> the graph in the paper to understand the ideas.
>
> The included testing cases work fine, but when I run the examples in the
> paper (Hillary sentences), it gives me this error:
> graph must contain the start vertex: visit
>
> I tried to fix it by modifying ConnectivityInspector.pathExists().
>
> Originally, it was
>
> --------------------------------------------------------------------------------------------------------------
>     Set<V> sourceSet =  connectedSetOf(sourceVertex);
>         return sourceSet.contains(targetVertex);
> --------------------------------------------------------------------------------------------------------------
>
> Then I added a few lines to catch the exception:
>
> ========================================================
>         //ron
>     Set<V> sourceSet = null;
>     try{
>     sourceSet = connectedSetOf(sourceVertex);
>     }
>     catch(IllegalArgumentException e)
>     {
>     return false;
>     }
>
>         return sourceSet.contains(targetVertex);
> ========================================================
>
> This seems fix the problem and gives correct output, but I am not sure what
> really happens deep in the algorithm and whether it is a good fix.
>
> Could you help on this issue?  Many thanks!
>
>
>
> Best regards,
>
> Ron
>