Re: [Boost-Users] BGL: Own vertex index property

From: Jeremy Siek (jsiek_at_[hidden])
Date: 2002-07-12 10:54:22

Hi Michael,

You can't add your own vertex_index property to an adjacency_list with
VertexList=vecS. The adjacency_list will just ignore it if you do. You can
if VertexList=listS, and example/adjacency_list.cpp is an example of this.

Also, you can add properties with names other than vertex_index_t to
adjacency_list with VertexList=vecS. For example, you could add your own
vertex_id_t property. However, this would *not* keep the vertex
descriptors from being invalidated, it would just give you a vertex_id_t
property that is stable.

I'm not sure if the above helps... I don't know the details of what you
are trying to do, but feel free to ask further questions.

Cheers,
Jeremy

On Fri, 12 Jul 2002, Michael Kettner wrote:
kettne> Hi,
kettne>
kettne> can someone give an example how to "not use the built-in vertex index, and
kettne> instead use a property to add my own vertex index property" (see page 223
kettne> BGL-book) for an adjacency_list?
kettne> My problem is that I'm using the vecS selector for the VertexList template
kettne> parameter and I need to remove vertices from my graph (but not frequently).
kettne> Every time I do this, my vertex descriptors are invalidated (as described in
kettne> the book). I need a solution so that I can remove some vertices and all my
kettne> vertex descriptors remain valid.
kettne>
kettne> Thanks in advance,
kettne>
kettne> Michael

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 Jeremy Siek                          http://php.indiana.edu/~jsiek/
 Ph.D. Student, Indiana Univ. B'ton   email: jsiek_at_[hidden]
 C++ Booster (http://www.boost.org)   office phone: [phone]
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