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Subject: Re: [boost] GSOC 2010  BGL Graph Connectives.
From: Andrew Sutton (andrew.n.sutton_at_[hidden])
Date: 20100331 15:57:55
>
> 1) Union ( undi, di ) returns an undi graph : I will convert the directed
> graph to undirected by adding arcs. Then, I unite them.
>
> 2) Union ( undi, di ) returns a di graph : I will consider the undirected
> graph as a directed one with two same arcs between vertices.
>
Is there any particular reason you are choosing this behavior? What
particular use cases does this address? It may be acceptable to not define
unions between undirected and directed graphs.
> 1) If the Union_graph 's properties is clearly declared, I will use
> typecasting. Nevertheless, the challenge is to deal with the nonintegral
> data type.
>
Type casting is not a viable solution.
> 2) If the Union_graph 's property is undeclared, I will try to integrate
> two properties. In particular, the vertices and edges of graph 1 will still
> keep their own properties; but they will also have graph_2 's properties, in
> which values will be initialized as 0.
>
Properties are never actually "undeclared". There is always a type that
represents the vertex and edge properties of a graph. You will have to look
a little closer at the implementation of the BGL graph data structures in
order to determine an acceptable approach.
Andrew Sutton
andrew.n.sutton_at_[hidden]
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