$ R
install.packages("igraph")
library(igraph)
# 乱数から成る100×100のデータ行列を作成
mat <- matrix(runif(10000), nr=100)
png("110212_graph.png")
par(mfrow=c(2,1))
plot(graph.adjacency(mat>=0.9, mode="undirected"))
plot(graph.adjacency(mat>=0.9, mode="undirected"), layout=layout.circle)
dev.off()