Re: [Boost-users] [BGL] resize/reserve on graph?

On Tue, Aug 9, 2011 at 3:13 PM, Geoff Hilton mailto:geoff.hilton@t-optlogic.com> wrote:

If I know that during the execution of the algorithm the graph size must be grown by X number of vertices in one go, is there a way this can be done to avoid multiple allocations such as when using std::vector's reserve(..) or resize(..) member functions without subverting the BGL's documented interface? Currently I use a for loop which iterates over add_vertex(vertex_property, graph). Can a reserve and/or resize equivalent otherwise please be added somewhere?

Thank you, Geoff

On 09/08/2011 6:12 PM, Anil Ramapanicker wrote: I think you are asking about implicit graph where vertices and edges are unknown at the begining and they are added during the execution of an algorithm. You can do it in two ways a) If you are using internal properties then add_vertex( vertex_whatever,g) will work b) If you are using exterior property map then use vector_property_map since the size is unknown

http://www.boost.org/doc/libs/1_47_0/libs/property_map/doc/vector_property_m...

Anil

That's exactly what I'm already doing. I'm asking because true, at first I do invariably have to use add_vertex(..), but later on I know exactly how many vertices by which to grow the graph at a time due to the algorithm I'm implementing and I wish to add them in as few memory allocations as possible (preferably one) to the existing graph. Thus, something like std::vector's resize/reserve or an equivalent would be useful. Thank you, Geoff