Re: [Boost-users] BGL graph library biconnected components

From: Aaron Windsor (aaron.windsor_at_[hidden])
Date: 2007-03-20 21:02:05

On 3/20/07, Greg Reynolds <gmr001_at_[hidden]> wrote:
> Hi Aaron,
>
> Thanks for the response.
>
> It turns out that I was being a bit dim; I didn't realise that long paths
> of vertices, e.g. 1--2--3--4--5 turn into lots of biconnected components
> : it's not something that the previous (non-boost) implementation of
> biconnected components I used did.
>
> Your comments on the code were interesting - is the second parameter to
> the property map really necessary? I have used lots of property maps and
> have never used this - have I just been lucky? :)
>

If you don't explicitly pass the second parameter, it defaults to an identity
property map (a map id where get(id, v) = v for all values v.) So you don't
really need to pass the second argument if the values in the domain of the
property map are actually a block of contiguous integers starting with 0
(Note that this is actually the case for vertex descriptors if you use a vector
to store vertices in the adjacency_list template.) But for any other case,
you'd need to supply a map as the second parameter.

Regards,
Aaron