Re: [igraph] igraph union methods

[Gábor Csárdi]

You did not tell us whether you're using R, Python or C. The set
methods are unfortunately not very good at using attributes, a
workaround solution would be to create edge lists from the graphs,
merge the edge lists and then create a new igraph.

In R, get.edgelist() can return a symbolic edgelist based on the
'name' attribute, then you can use rbind() and unique() to merge the
symbolic edge lists and finally create a new graph with
graph.edgelist(). You have to handle vertex and edge attributes
manually if you need to keep them.

Gabor

On Fri, Oct 10, 2008 at 5:18 PM,  <address@hidden> wrote:
>
> Hi,
>
> I was wondering what was the best technique to merge multiple graphs.
> The union methods appears to merge the nodes based on node id. If I
> wanted to merge the graphs based on a label in the node, whats the best
> approach? I was thinking of adding both graphs, iterating through all
> the vertices and removing duplicate labels and adding new edge that
> belong to the ones that got removed. Is this a sensible approach?
>
> Thanks,
> Venura
>
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-- 
Gabor Csardi <address@hidden>     UNIL DGM