Compute the direct product of two graphs
Examples
library(igraph)
g <- make_ring(4)
h <- make_full_graph(2)
graph_direct(g, h)
#> IGRAPH f6f2f14 UN-- 8 8 --
#> + attr: name (v/c)
#> + edges from f6f2f14 (vertex names):
#> [1] 1-1--2-2 2-1--1-2 2-1--3-2 2-2--3-1 3-1--4-2 3-2--4-1 1-1--4-2 1-2--4-1
