Re: [Boost-users] Boost-users Digest, Vol 2928, Issue 3

Subject: Re: [Boost-users] Boost-users Digest, Vol 2928, Issue 3
From: Nicolas Saunier (nicolas.saunier_at_[hidden])
Date: 2011-12-07 15:28:02

Hi,

On 11-12-07 02:21 PM, boost-users-request_at_[hidden] wrote:
> Message: 6
> Date: Wed, 7 Dec 2011 14:19:46 -0500 (EST)
> From: Jeremiah Willcock<jewillco_at_[hidden]>
> To:boost-users_at_[hidden]
> Subject: Re: [Boost-users] [BGL] Issue using connected_components
> Message-ID:<alpine.LRH.2.00.1112071418120.25335_at_[hidden]>
> Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
>
> On Wed, 7 Dec 2011, Nicolas Saunier wrote:
>
>> >  Hi,
>> >
>> >  here is a simplified code sample that I cannot get to work. I use bundled
>> >  properties for an undirected graph and I do not find what should be the type
>> >  of the component map (or property map) that should be passed as the second
>> >  argument of the connected_components function. The sample is useless since
>> >  only integers are for vertices.
> The normal vector_property_map class does not work for adjacency_list
> graphs with a listS vertex container unless you define a vertex_index_map.
> Is there a reason you can't use vecS as the vertex container in your
> graph?  If you truly need listS, you will need to create a vertex index
> map, fill it in before you create the property map, and pass it to the
> vector_property_map constructor (and as a type argument to that class).
>
> -- Jeremiah Willcock

Thanks for replying. The problem, and that may seem too simple or silly 
to people familiar with the library, is that I have no idea what should 
be the type of the component map to pass. I tried to declare the 
components variable as:

vector< graph_traits<FeatureGraph>::vertices_size_type > 
components(num_vertices(g));

And it does not work either. What is the type of the component map, the 
second argument of connected_components? Can you give me an example of a 
type that would work (compile and return the correct results)?

Thanks!

Nicolas
-- 
Nicolas Saunier, ing. jr, Ph.D.
Professeur Adjoint / Assistant Professor
Département des génies civil, géologique et des mines (CGM)
École Polytechnique de Montréal
http://nicolas.saunier.confins.net