On Tue, 23 Mar 2010, Matthias Walter wrote:

Hi!

Is there any way to reconnect an edge in a graph? I'm interested in doing so while retaining a property map. Thus remove_edge and add_edge are not a solution, I think. If not, may it worth to add such a concept?

I do not believe there is a way to do that other than by messing with internal data structures. Is copying the properties over too slow for what you're doing? If the properties are large/slow to copy, would having a shared_ptr as the property stored in the graph help? -- Jeremiah Willcock

On 04/01/2010 05:32 PM, Andrew Sutton wrote:

...

Is there any way to reconnect an edge in a graph? I'm interested in

...

doing so while retaining a property map. Thus remove_edge and add_edge are not a solution, I think. If not, may it worth to add such a concept?

I do not believe there is a way to do that other than by messing with internal data structures. Is copying the properties over too slow for what you're doing? If the properties are large/slow to copy, would having a shared_ptr as the property stored in the graph help?

I wrote an algorithm a couple years ago that did something similar - conceptually temporarily removing and re-adding edges. Rather than modify the actual graph, I just used a color map to mask the edges that were temporarily being excluded.

Would that be an option for your application?

I looked deeper into the implementation of adjancency_list and figured out that indeed it doesn't look feasible there. For my application, I was able to implement it by copying the properties. I just thought of a generic way that might be faster than removing and adding. If someone has a good idea how to implement it nicely, such that edge-index-maps are retained, this could be a nice feature. But for me it's "solved", so we're not in a hurry :) best regards Matthias Walter