Number of automorphisms
Calculate the number of automorphisms of a graph, i.e. the number of isomorphisms to itself.
automorphisms(graph, sh = "fm")
- The input graph, it is treated as undirected.
- The splitting heuristics for the BLISS algorithm. Possible values
: first non-singleton cell,
: first largest non-singleton cell,
: first smallest non-sing
An automorphism of a graph is a permutation of its vertices which brings the graph into itself.
This function calculates the number of automorphism of a graph using the
BLISS algorithm. See also the BLISS homepage at
- A named list with the following members:
group_size The size of the automorphism group of the input graph, as a string. This number is exact if igraph was compiled with the GMP library, and approximate otherwise. nof_nodes The number of nodes in the search tree. nof_leaf_nodes The number of leaf nodes in the search tree. nof_bad_nodes Number of bad nodes. nof_canupdates Number of canrep updates. max_level Maximum level.
Tommi Junttila and Petteri Kaski: Engineering an Efficient Canonical Labeling Tool for Large and Sparse Graphs, Proceedings of the Ninth Workshop on Algorithm Engineering and Experiments and the Fourth Workshop on Analytic Algorithms and Combinatorics. 2007.
## A ring has n*2 automorphisms, you can "turn" it by 0-9 vertices ## and each of these graphs can be "flipped" g <- make_ring(10) automorphisms(g)