Re: [Boost-users] [BGL] graph without parallel edges

From: Alejandro Aragón (alex_aragon_at_[hidden])
Date: 2006-02-28 01:23:10

Alejandro Aragón wrote:
> Doug Gregor wrote:
>> On Feb 20, 2006, at 3:43 PM, Alejandro Aragón wrote:
>>
>>> Hi everyboty,
>>>
>>> Can someone point to a concrete example of a graph without parallel
>>> edges???  I am using setS as my container for the edges but I still
>>> insert edges twice in my graph algorithm.  Thank you,
>> When using setS for the OutEdgeListS, insertion of a parallel edge 
>> should have no effect at all. If this isn't the behavior you are 
>> seeing, we have a bug and we'll need to fix it.
>>
>> 	Doug
> 
> Well, for some reason, the boolean inserted turns out to be always 1. 
> I'll run an example and I will let you know.
> 
> a^2

Well, it seems now that the problem is fixed.  I was using a directedS 
graph with setS for the OutEdgeListS.  I changed that to undirectedS and 
now edges are not added twice as before.  I thought that setS completely 
discarded parallel edges no matter of the choice of the directivity of 
the graph.  It doesn't make sense to me that you can have a directed 
graph with a disjoint set container that doesn't allow the parallel edge 
behavior.  I think there should be some warning if you use setS with 
directedS right?

a^2