Re: [igraph] PageRank & Hello.

[Gábor Csárdi]

Hi Martin,

On Mon, May 11, 2009 at 6:00 PM, Martín Conte Mac Donell
<address@hidden> wrote:
> Hello,
>
> I'm who posted #365817 recently in launchpad[0] about pagerank/arpack error.
>
> In addition to that i was found some strange results. If you look the graph
> i'm attaching you'll see that vertex "3" should have more pagerank that "1"
> (isn't it?).

No, I think our page rank implementation is correct, at least for this graph.

> g <- graph( c(0,1,1,0, 4,3,5,3,6,3,2,3) )
> A <- get.adjacency(g)
> page.rank(g)$vector
[1] 0.39617763 0.39617763 0.02370186 0.11283730 0.02370186 0.02370186 0.02370186
> norm <- function(x) x/sum(x)
> norm(eigen(t(A) * 0.85 + 0.15/7)$vectors[,1])
[1] 0.39617763 0.39617763 0.02370186 0.11283730 0.02370186 0.02370186 0.02370186

Best,
Gabor

[...]

-- 
Gabor Csardi <address@hidden>     UNIL DGM