Arranging arrows between points nicely in ggplot2

Question

(note - this is the same piece of work as using multiple size scales in a ggplot, but I\'m asking a different question)

I\'m trying to construct a plot which shows

Answer 1

I thought since nobody has given a solution i would provide an example of package more aimed a this sort of problem:

vecs  <- data.frame(vecs =1:6,size=sample(1:100,6))
edges <- data.frame(from=sample(1:6,9,replace=TRUE), to=sample(1:6,9,replace=TRUE))

library(igraph)

g      <- graph.data.frame(edges, vertices = vecs, directed = TRUE)
coords <- cbind(sample(1:20,6), sample(1:20,6))


plot(g, vertex.size=V(g)$size,vertex.color="white",layout=coords,axes=TRUE)

This will at least solve your arrows before the circle issue and also when there are reciprocal arrows it will adjusts them with the curved lines as in 2<->5:

(arrrow sizes, line widths, colours etc can of course be modified)