[igraph] kind of a zoom problem with plotting

[Yannick Rochat]

Hi there ! (long time no see…)

I've got a problem when trying to plot a graph two times, with the same layout but different vertex sizes. The following code will reproduce this problem :

g1 <- erdos.renyi.game(25,.2)
g1$layout <- layout.fruchterman.reingold(g1)
g2 <- g1
V(g2)$size <- 15

V(g2)[0:4]$size <- 45
plot(g1)
quartz()
plot(g2)

In fact, I'm plotting the network of a twitter debate every minute, and then I merge them into a video. I use the layout of the network with all the edges for every previous network. I've decided to highlight the last contributing vertices by doubling their size for a few frames, but this causes the plot (or frame ?) size to get slightly modified and in the end, we can observe some frenetic zooming/dezooming.

It seems that the vertex sizes, or other arguments, are able to modify the plotting values. Would you know how I can fix that ?

Best regards,

Yannick


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