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## Re: [igraph] Named vertexes from imported adjacency matrix

 From: Szabolcs Feczak Subject: Re: [igraph] Named vertexes from imported adjacency matrix Date: Sun, 1 Jun 2008 02:18:42 +1000

Thanks Gabor,

it works, however meanwhile Im trying to do the same with the python interface
as I might have to do batch processing and it seems to be easier that way

How would I do the same thing in python ?

what I have got so far is:

from igraph import *
import csv
m = []
for row in r:
m.append( [int(i) for i in row] )

however I have realized that it works a bit different and the Adjacency function ignores non numeric values
so I had to edit the csv by hand and remove the first column and the first row

also, how would I display the weights on the graphs
what I would like to achieve is something like this

http://feczo.nmi.rulez.org/sna/2232.png

it would be nice to have both the line width and the frequencies

another question, is it possible to measure Freeman node betwenness of the graph ?
to see in how many percentage does it compare to a perfect star ...

and a last question ...
is it possible to get the standard deviation of the average produced by Graph.density() ?

Thanks again

S.

ps: actually I have been subscribed, but I have used a different address to post last time

On Thu, May 22, 2008 at 7:01 AM, Gabor Csardi <address@hidden> wrote:
Szabolcs,

in the next igraph version the row names will be added automatically
development version.

In the meanwhile, you can use the fact that graph.adjacency keeps
the order of the vertices:

a <- matrix(sample(0:1, 16, rep=TRUE), 4)
rownames(a) <- colnames(a) <- letters[1:4]
V(g)\$name <- rownames(a)
g

gives:

Vertices: 4
Edges: 9
Directed: TRUE
Edges:

[0] a -> c
[1] b -> b
[2] b -> c
[3] c -> a
[4] c -> b
[5] c -> c
[6] c -> d
[7] d -> b
[8] d -> d

G.

ps. please consider joining the list, otherwise you might miss some
can cause delay, even a couple of days. Thanks.

On Thu, May 22, 2008 at 01:45:32AM +1000, Szabolcs Feczak wrote:
> Hi,
>
> I have just started to use this tool with R, so far I have achieved
> to read my adjacency matrix from CVS and plot the graph (with the method
> below),
> however I would like to have the vertex labels as the identifiers
> on the rows/columns not the automatically assigned numbers
> how can I do this automatically (I have more actors, the below is just a
> truncated file)
>
>
>
> Thanks
>
> S.
>
> ps: great tool
> -------------------
>
>
>        123827 375857 530241 547613 661825 771302
> 123827      0      1      0      0      0      1
> 375857      1      0      0      0      0      1
> 530241      0      0      0      0      1      0
> 547613      0      0      0      0      0      1
> 661825      0      0      1      0      0      0
> 771302      1      1      0      1      0      0
> FALSE))
> Vertices: 6
> Edges: 10
> Directed: TRUE
> Edges:
>
> [0] 0 -> 1
> [1] 0 -> 5
> [2] 1 -> 0
> [3] 1 -> 5
> [4] 2 -> 4
> [5] 3 -> 5
> [6] 4 -> 2
> [7] 5 -> 0
> [8] 5 -> 1
> [9] 5 -> 3
> 1,check.names = FALSE))
> > tkplot(g8, layout=layout.fruchterman.reingold, vertex.size=12, vertex.label=V
> (g8)\$name)

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