About igraph releases and other things

December 19, 2006

This is a new major release, it contains many new things: geometric random graphs, creating a graph with attributes from a data frame in R, local transitivity, etc.

`bonpow`

function ported from SNA to calculate Bonacich power centrality`get.adjacency`

supports attributes now, this means that it sets the colnames and rownames attributes and can return attribute values in the matrix instead of 0/1`grg.game`

, geometric random graphs`graph.density`

, graph density calculation- edge and vertex attributes can be added easily now when added new
edges with
`add.edges`

or new vertices with`add.vertices`

`graph.data.frame`

creates graph from data frames, this can be used to create graphs with edge attributes easily`plot.igraph`

and`tkplot`

can plot self-loop edges now`graph.edgelist`

to create a graph from an edge list, can also handle edge lists with symbolic names`get.edgelist`

has now a ‘names’ argument and can return symbolic vertex names instead of vertex ids, by default id uses the`name`

vertex attribute is returned- printing graphs on screen also prints symbolic symbolic names
(the
`name`

attribute if present) - maximum flow and minimum cut functions:
`graph.maxflow`

,`graph.mincut`

- vertex and edge connectivity:
`edge.connectivity`

,`vertex.connectivity`

- edge and vertex disjoint paths:
`edge.disjoint.paths`

,`vertex.disjoint.paths`

- White’s cohesion and adhesion measure:
`graph.adhesion`

,`graph.cohesion`

- dimacs file format added
`as.directed`

handles attributes now- constraint corrected, it handles weighted graphs as well now
- weighted attribute to
`graph.adjacency`

- spinglass-based community structure detection, the Joerg Reichardt –
Stefan Bornholdt algorithm added:
`spinglass.community`

`graph.extended.chordal.ring`

, extended chordal ring generation`no.clusters`

calculates the number of clusters without calculating the clusters themselves- minimum spanning tree functions updated to keep attributes
`transitivity`

can calculate local transitivity as well- neighborhood related functions added:
`neighborhood`

,`neighborhood.size`

,`graph.neighborhood`

- new graph generators based on vertex types:
`preference.game`

and`asymmetric.preference.game`

- attribute handling bug when deleting edges corrected
- GraphML escaping and NaN handling corrected
- bug corrected to make it possible compile the R package without the libxml2 library
- a bug in Erdos-Renyi graph generation corrected: it had problems with generating large directed graphs
- bug in constraint calculation corrected, it works well now
- fixed memory leaks in
`igraph_read_graph_graphml`

- error handling bug corrected in
`igraph_read_graph_graphml`

- bug corrected in R version of
`graph.laplacian`

when normalized Laplacian is requested - memory leak corrected in
`get.all.shortest.paths`

in the R package