[Boost-users] [Graph] Reserving graph memory (again)

Subject: [Boost-users] [Graph] Reserving graph memory (again)
From: Sensei (senseiwa_at_[hidden])
Date: 2015-04-01 10:26:26

Dear all,

Reading all the documentation online about memory reservation in a 
graph, I am still wondering if it would be possible to reserve memory in 
advance.

With a vecS container it would be quite an advantage to reserve memory, 
but let me be clear, I am not saying that I know the number of edges in 
advance, so CRS isn't an option.

Until now I know of two ways to do this. The first is to add & remove an 
edge:

         add_edge(0, num_vertices(g) + list.size() - 1, g);
         remove_edge(0, num_vertices(g) + list.size() - 1, g);

however, it won't work in my context since I could (as you see from the 
code) add edges to an existing graph, and I am getting weird results. I 
am sure this is due to my code, however, add/remove isn't really a neat 
solution. The second option is weird:

        g.m_vertices.resize(list.size() - 1);

This could be used, but m_* members should, as far as I understand, be 
private or protected.

Is there any other nice possibility? For instance, a static function in 
the traits that reserves memory? In case, why this cannot be done by BGL 
APIs?

Thanks!