Re: [igraph] edge indexing

[Elena Tea Russo]

Thank you too, Gabor.

I can just guess the problems that a "fixed" indexing in a graph could lead to. 
I suppose neither edges and vertex selectors are then reliable after I modify 
my graph?

 I'll have to rethink a bit my code, but I luckily can manage my problem 
throughout an adjacency matrix.

Thanks again!

Et Russo

Il giorno 15/giu/2015, alle ore 15:20, Gábor Csárdi <address@hidden> ha scritto:

> Hi,
> 
> I understand that reassigning ids is very difficult to work with, it
> was a decision long time ago, and unfortunately we have to live with
> it now, and for the foreseeable future.
> 
> A useful way of thinking about this, especially in R, is that igraph
> _never_ modifies a graph. It always creates new graphs. So when you
> say delete.edges(), the old graph is not modified, and a new graph is
> created based on it.
> 
> In general, you cannot assume anything about the relationship between
> the internal ids of the old graph and the new graph.
> 
> I hope this helps,
> Gabor