Re: [igraph] problems with parameters in barabasi.game()

[Mario Lavezzi]

Gabor, thanks a lot. It seems to work but, most of the times, after 
following your suggestions, I get a message like this:

--------------------------------------------------------------------
*** caught segfault ***
address (nil), cause 'memory not mapped'

Traceback:
1: .Call("R_igraph_degree_sequence_game", as.numeric(out.deg), 
as.numeric(in.deg),     as.numeric(method), PACKAGE = "igraph")
2: degree.sequence.game(degreeSeq, method = "vl")

Possible actions:
1: abort (with core dump, if enabled)
2: normal R exit
3: exit R without saving workspace
4: exit R saving workspace

-----------------------------------------------------------

...and have to stop..

I understand this has to do with the way R works, but I have not found 
any useful help on this in the web
(by the way, I use R 2.6.2 on Linux Ubuntu 8.04)

Mario

> Mario, I would try 'sample' first, e.g. 
>
> degs <- sample(1:1000, 1000, replace=TRUE, prob=(1:1000)^-2)
> g <- degree.sequence.game(degs, method="vl")
>
> Note that it is not always possible to realize a given degree sequence,
> e.g. if the sum of degrees is odd, then it is trivially impossible.
>
> G.
>   
--
Andrea Mario Lavezzi
Dipartimento di Studi su Politica, Diritto e Società
Università di Palermo
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