igraph 2.1.2

Bug fixes

• adjacent_vertices() and incident_edges() are now correct if the "return.vs.es" option is FALSE (@stibu81, #1605, #1606).

• Fix protection errors reported by rchk (#1592).

• Fix the incorrect handling of the sample parameter in sample_motifs() and ensure that the default sample.size is integer (#1568).

Documentation

• Clarify what type of graph each community detection function supports.

• Improve ?read_graph and ?write_graph documentation.

• Improve all_simple_paths() documentation.

• cluster_optimal() does support directed graphs.

Testing

• Test handling of "return.vs.es" in several functions (@stibu81, #1610).