Re: [igraph] add vertex attributes from a data.frame

[Gábor Csárdi]

Hi Simone,

On Thu, Mar 24, 2011 at 3:50 PM, Simone Gabbriellini <address@hidden> wrote:
> Hello List,
>
> i am trying to add a vertex attribute from a data.frame like:
>
>>
> who_invited_whom
>
>    invited inviter
> 1   user139  user83
> 2   user140  user83
> 3   user141  user83
> 4   user142  user83
> 5   user143  user83
> 6   user144  user83
>
> I would like to add an attribute "invitedby" to vertex of type==0. I am 
> trying this:
>
> V(g)[type==0 & name %in% 
> who_invited_whom$invited]$invitedby<-who_invited_whom$inviter

You get the warning because the number of vertices you select on the
left hand side does not match the length of the right hand side.

But anyway, I think this is wrong, because nothing ensures that the
order of the vertices is the same on the left and right hand side. I
think you want something like

V(g)$invitedby <- as.character(NA)
ord <- match(who_invited_whom$invited, V(g)$name[V(g)$type==0])
V(g)$invitedby[V(g)$type==0][ord] <- as.character(who_invited_whom$inviter)

I haven't tested it much, it seems to work for the toy data I just made up.

Best,
Gabor

> Warning message:
> In graph[[9]][[3]][[name]][index] <- value :
>  il numero di elementi da sostituire non `e un multiplo della lunghezza di 
> sostituzione
>
> Why am I getting the warning? Am I doing something wrong here?
>
> thanks for your help!
>
> best regards,
> Simone
> _______________________________________________
> igraph-help mailing list
> address@hidden
> http://lists.nongnu.org/mailman/listinfo/igraph-help
>



-- 
Gabor Csardi <address@hidden>     MTA KFKI RMKI