[R] igraph and tkgraph

[Tom Backer Johnsen]

Gabor:

Actually, I meant a script GUI management of ugraph I managed to locate 
on the net.  Disregarding that, thank you for the suggestions.  igraph 
is definitly a non-trivial affair, with a lot of options and 
corresponding flexibility.  I made some changes to what you wrote:

A <- matrix(sample(c(-1, 0, 0, 0, 1), 25, replace=T), 5)
g <- graph.adjacency(A, mode="directed", weighted=T, diag=F)
E(g)$lty <- ifelse(E(g)$weight > 0, 1, 2)
tkplot (g, layout=layout.kamada.kawai)

This gives me something that is very close to what I want, apart from a 
suspicion that if the relations between two vertices is non-symmetric, 
only one of the is shown.  Is it possible to have a pair of, say 
slightly curved arrows as edges between them in that case?

Tom

Gábor Csárdi wrote:
> Tom, you mean 'tkplot' in the igraph package? Look at ?igraph.plotting
> on how to set up plotting parameters, e.g. if you want different line
> types for the positive/negative relations, then you can make use of
> the 'lty' parameter:
> 
> A <- matrix(sample(c(-1,0,1), 100, replace=TRUE), 10)
> g <- graph.adjacency(A, mode="upper", weighted=TRUE, diag=FALSE)
> E(g)$lty <- ifelse(E(g)$weight > 0, 1, 2)
> tkplot(g, layout=layout.kamada.kawai)
> 
> Gabor
> 
> On Fri, Nov 14, 2008 at 12:40 PM, Tom Backer Johnsen
> <backer at psych.uib.no> wrote:
>> I have a number of (directed) graphs based on social groups, where the
>> members have expresed likes and dislikes in respect to the other members.
>>  tkgraph makes it simple to draw the graphs in a very pleasing way, but I
>> would like to differentiate between positive and negative relations in the
>> graph by having the edges for the negative relations dashed and the positive
>> ones continuous.
>>
>> Is that possible?  If so how?
>>
>> Tom
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
> 
> 
> 


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| Tom Backer Johnsen, Psychometrics Unit,  Faculty of Psychology |
| University of Bergen, Christies gt. 12, N-5015 Bergen,  NORWAY |
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| Email : backer at psych.uib.no    URL : http://www.galton.uib.no/ |
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