Calculate the number of automorphisms of a graph, i.e. the number of
isomorphisms to itself.
Usage
automorphisms(graph, sh = "fm")
Arguments
graph
The input graph, it is treated as undirected.
sh
The splitting heuristics for the BLISS algorithm. Possible values
are: f: first non-singleton cell, fl: first
largest non-singleton cell, fs: first smallest non-sing
Value
A named list with the following members:
group_sizeThe 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_nodesThe number of nodes in the search tree.
nof_leaf_nodesThe number of leaf nodes in the search tree.
nof_bad_nodesNumber of bad nodes.
nof_canupdatesNumber of
canrep updates.
max_levelMaximum level.
Details
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
http://www.tcs.hut.fi/Software/bliss/index.html.
References
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.