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igraph: error when setting size and shape of vertices

2 messages · robbie.heremans at telenet.be, Gábor Csárdi

robbie.heremans at telenet.be
# 
When the shape of all vertices is set to "square" and the size of the vertices is also set, one get following error (commands attached):

Error in l[[which.min(sapply(l, function(p) (p[1] - x0)^2 + (p[2] - y0)^2))]] :
        attempt to select less than one element

Is there a way to solve this problem?

Robbie

## Load the igraph package
library(igraph)

## Create and plot a small graph
g <- graph( c(0,1, 0,2, 1,2, 2,3), n=4, directed = FALSE)
plot(g)

V(g)$size<-c(10,15,20,30)
plot(g) #OK

V(g)$shape<-c("circle","circle","circle","square")
plot(g) #OK

V(g)$shape<-c("circle","circle","square","square")
plot(g) #OK

V(g)$shape<-c("circle","square","square","square")
plot(g) #OK

V(g)$shape<-c("square","square","square","square")
plot(g) #Error in l[[which.min(sapply(l, function(p) (p[1] - x0)^2 + (p[2] - y0)^2))]] :
        #attempt to select less than one element

V(g)$shape<-c("square","square","circle","square")
plot(g) #OK

## Same without changing size
g <- graph( c(0,1, 0,2, 1,2, 2,3), n=4, directed = FALSE)
V(g)$shape<-c("square","square","square","square")
plot(g) #OK
Gábor Csárdi
# 
Yep, this is a bug, thanks for reporting it. It only happens with the
square shape, so until it is a corrected, a workaround is using
"rectangle" shape, with equal vertical and horizontal sizes:

g <- graph.ring(4)
g$layout <- layout.circle
V(g)$size <- seq_len(vcount(g)) * 10
V(g)$size2 <- V(g)$size

plot(g, vertex.shape="square")       # gives an error
plot(g, vertex.shape="rectangle")    #  works

I have tried this only on the not-yet-released 0.6 version, please
tell me if it does not work on 0.5.1.

Best,
Gabor
On Wed, Feb 4, 2009 at 11:26 AM, <robbie.heremans at telenet.be> wrote: