[igraph] read.graph query

[Thomas]

When I write out and then read in a graph, it's average path length  
changes - code and output below. Anyone know why this is happening?  
I'm running iGraph on R.

>g <- watts.strogatz.game(1,500,5,0.1)
>g <- simplify(g, remove.multiple = TRUE, remove.loops = TRUE)
> transitivity(g)
[1] 0.3620622
> average.path.length(g)
[1] 3.514822
> write.graph(g, "SmallWorldEL.txt", format=c("edgelist"))
> h <- read.graph("SmallWorldEL.txt", format=c("edgelist"))
> average.path.length(h)
[1] 4.872057
> transitivity(h)
[1] 0.3620622

Thank you,

Thomas

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