
library(igraph) ; igraph.options(print.full=TRUE)

g1 <- graph.ring(10)
g2 <- graph.star(11, center=11, mode="undirected")
gu <- graph.union(g1, g2)
gu

gdu <- graph.disjoint.union(g1, g2)
gdu

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graph.difference(gu, g1)

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graph.intersection(gu, g2)

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graph.complementer(g2)

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graph.compose(gu, g1)

