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.

Changes in the R interface

  • 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
  •, 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
  • 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:
  • 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: and

Bugs corrected

  • 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