A complementer graph contains all edges that were not present in the input graph.
Details
complementer() creates the complementer of a graph. Only edges
which are not present in the original graph will be included in the
new graph.
complementer() keeps graph and vertex attriubutes, edge
attributes are lost.
See also
Other functions for manipulating graph structure:
+.igraph(),
add_edges(),
add_vertices(),
compose(),
connect(),
contract(),
delete_edges(),
delete_vertices(),
difference(),
difference.igraph(),
disjoint_union(),
edge(),
igraph-minus,
intersection(),
intersection.igraph(),
path(),
permute(),
rep.igraph(),
reverse_edges(),
simplify(),
transitive_closure(),
union(),
union.igraph(),
vertex()
Author
Gabor Csardi [email protected]
Examples
## Complementer of a ring
g <- make_ring(10)
complementer(g)
#> IGRAPH 15f26be U--- 10 35 -- Ring graph
#> + attr: name (g/c), mutual (g/l), circular (g/l)
#> + edges from 15f26be:
#> [1] 1-- 9 1-- 8 1-- 7 1-- 6 1-- 5 1-- 4 1-- 3 2--10 2-- 9 2-- 8 2-- 7 2-- 6
#> [13] 2-- 5 2-- 4 3--10 3-- 9 3-- 8 3-- 7 3-- 6 3-- 5 4--10 4-- 9 4-- 8 4-- 7
#> [25] 4-- 6 5--10 5-- 9 5-- 8 5-- 7 6--10 6-- 9 6-- 8 7--10 7-- 9 8--10
## A graph and its complementer give together the full graph
g <- make_ring(10)
gc <- complementer(g)
gu <- union(g, gc)
gu
#> IGRAPH 8370bcd U--- 10 45 --
#> + attr: name_1 (g/c), name_2 (g/c), mutual_1 (g/l), mutual_2 (g/l),
#> | circular_1 (g/l), circular_2 (g/l)
#> + edges from 8370bcd:
#> [1] 9--10 8--10 8-- 9 7--10 7-- 9 7-- 8 6--10 6-- 9 6-- 8 6-- 7 5--10 5-- 9
#> [13] 5-- 8 5-- 7 5-- 6 4--10 4-- 9 4-- 8 4-- 7 4-- 6 4-- 5 3--10 3-- 9 3-- 8
#> [25] 3-- 7 3-- 6 3-- 5 3-- 4 2--10 2-- 9 2-- 8 2-- 7 2-- 6 2-- 5 2-- 4 2-- 3
#> [37] 1--10 1-- 9 1-- 8 1-- 7 1-- 6 1-- 5 1-- 4 1-- 3 1-- 2
isomorphic(gu, make_full_graph(vcount(g)))
#> [1] TRUE