Hi Hugues,


On Jan 29, 2004, at 8:36 AM, Hugues Joly wrote:


<excerpt>Hi,

   I'm wondering if defining a graph as a

pointer-linked vertex list is  compatible with the

subgraph paradigm.


Presumably, an adjacency list having its vertex

descriptor defined as a pointer to a vertex object

would fulfil our needs.  But how this technique would

behave when we deal with a subgraph having local

vertex descriptors?

</excerpt>

Let's see... here's the requirements on the Graph template parameter

of subgraph:


<fontfamily><param>Times</param><bigger><bigger>A graph type modeling
<color><param>0000,0000,EEEE</param>VertexMutableGraph</color> and
<color><param>0000,0000,EEEE</param>EdgeMutableGraph</color>. Also the
graph must have internal
</bigger></bigger></fontfamily><fontfamily><param>Courier</param><x-tad-bigger>vertex_index</x-tad-bigger></fontfamily><fontfamily><param>Times</param><bigger><bigger>
and
</bigger></bigger></fontfamily><fontfamily><param>Courier</param><x-tad-bigger>edge_index</x-tad-bigger></fontfamily><fontfamily><param>Times</param><bigger><bigger>
properties. The vertex indices must be maintained automatically by the
graph, whereas the edge indices will be assigned by the
</bigger></bigger></fontfamily><fontfamily><param>Courier</param><x-tad-bigger>subgraph</x-tad-bigger></fontfamily><fontfamily><param>Times</param><bigger><bigger>
class implementation.</bigger></bigger></fontfamily>


Ok, so the vertex indices are not automatically maintained in
adjacency_list when VertexList=listS, so

that won't work. Sorry. (I'm sure it would be possible to change
subgraph to lift this restriction,

but that of course would take time).


-Jeremy


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Jeremy Siek					http://php.indiana.edu/~jsiek/

 Ph.D. Student, Indiana Univ. B'ton	email: jsiek@osl.iu.edu

 C++ Booster (http://www.boost.org)	office phone: (812) 856-1820

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