In an attempt to bring the R interface of igraph closer to the recent developments of the C core, we have released R-igraph 1.2.7, the seventh bugfix release of the 1.2 series. This version updates the C core of igraph within the R interface to version 0.8.5, which, while still several versions behind the mainline C core, fixes a range of bugs compared to the previous release and introduces a few new functions.

This release is only the beginning; in the next few months we aim to process most of the issues on the Github issue tracker, close the ones that are not relevant any more, fix the ones that should be fixed, and then proceed with updating the R interface to version 0.9.4 of the C core, which is the most recent C core version at the time of writing.

Release Notes

Added:

• cluster_leiden() added as an interface to the Leiden community detection algorithm in the C core of igraph (#399.
• cluster_fluid_communities() added as an interface to the fluid communities algorithm of the C core of igraph (#454.

Fixed:

• make_lattice() correctly rounds length to the nearest integer while printing a warning (#115.
• make_empty_graph(NULL) now prints an error instead of producing an invalid graph (#404).
• make_graph(c()) now produces an empty graph instead of printing a misleading error message (#431).
• Printing a graph where some edges have NA as the names of both endpoints does not produce a misleading error message any more (#410).
• The types argument of functions related to bipartite graphs now prints a warning when the types are coerced to booleans (#476).
• Betweenness normalisation no longer overflows (#442).
• layout_with_sugiyama() returns a layout of type matrix even if there is only one vertex in the graph (#408).
• Plotting a null graph (i.e. a graph with no vertices) does not throw an error any more (#387).

Deprecated:

• The membership argument of modularity.matrix() is now deprecated as the function never needed it anyway.
• modularity() now prints a warning when it is applied on a directed graph because the implementation in igraph’s C core does not support directed graphs as of version 0.8.5. The warning will be turned into an error in the next minor (1.3.0) version of the R interface; the error will be removed later when the C core is updated to a version that supports modularity for directed networks.
• transitivity() now prints a warning when its local variant (type="local") is called on a directed graph or a graph with multiple edges beecause the implementation in the C core of igraph does not work reliably in these cases as of version 0.8.5. The warning will be turned into an error in the next minor (1.3.0) version of the R interface; the error will be removed later when the C core is updated to a version that supports transitivity for networks with multiple edges.

Misc:

• Documentation improvements.