My personal take is that they do have similar function (they "extract" communities), but they have a general different type of output. in label propagation you'd end up with an id for each vertex (the vertex id that is the centroid for the community each vertex belongs to), while i'd expect from linlog something like an (x,y) coordinate. is that correct?

On Wed, Mar 7, 2012 at 2:45 AM, Timmy Wilson <tim...@smarttypes.org> wrote: > Thank you everyone! > > I would love to see a comparison of force directed layouts > (specifically LinLog) and label propagation. > > I searched but alas nothing -- they seem to be oddly similar? > > The current, serial LinLog implementation -- > http://code.google.com/p/linloglayout/ -- uses Barnes-Hut simulation > -- n*log(n): > > http://en.wikipedia.org/wiki/Barnes%E2%80%93Hut_simulation > > I guess the root question is -- do you think it's reasonable to use > giraph for Barnes-Hut simulation? > > > > > On Tue, Mar 6, 2012 at 11:34 AM, Claudio Martella > <claudio.marte...@gmail.com> wrote: >> Hi, >> >> I'm not definitely familiar with the algorithm or implementation of >> LinLog, I've been just a user. It should be doable with Giraph if you >> can express it in terms of message-passing between vertices and >> without a dependency on a global view of the graph (except for the >> convergence criteria, such as total energy). >> >> Please consider that Giraph's data model is based on a directed graph, >> this should be a quite "interesting" constraint for you, if your >> implementation is going to modify energy associated with edges (you'd >> have two views over the undirected edge, one in each endpoint). >> >> In general, a good way of doing community analysis would be to look at >> algorithms that belong to the family of label-propagation clustering >> algorithms. >> >> >> Hope this helps, >> Claudio >> >> On Tue, Mar 6, 2012 at 3:28 PM, Timmy Wilson <tim...@smarttypes.org> wrote: >>> Hi giraph community, >>> >>> I'm interested in using giraph for distributed n-body simulation. >>> >>> Initially, i'm interested in force directed layouts -- ie, graph drawing: >>> >>> http://en.wikipedia.org/wiki/Force-based_algorithms_(graph_drawing) >>> >>> I'm interested specifically in Dr. Andreas Noack's LinLog energy model >>> -- which performs well w/ community detection: >>> >>> http://www.informatik.tu-cottbus.de/~an/GD/linlog.html >>> >>> I have a few examples of a serial implementation here: >>> >>> http://www.smarttypes.org/ >>> >>> The model maximizes the distance between all nodes while minimizing >>> the distance between connected nodes. >>> >>> Without getting into too much detail, i'm curious if anyone has >>> considered using giraph for force directed graph embedding (yet >>> another name for it)? >>> >>> I'm also considering something like http://www.mcs.anl.gov/petsc/ or >>> http://www.cs.cmu.edu/~scandal/alg/nbody.html -- which have fast >>> n-body simulation implementations (Barnes-Hut + Fast Multipole). >>> >>> That said, i think giraph may be a good fit -- curious what the >>> community thinks? >>> >>> >>> Thanks, >>> Timmy Wilson >>> Cleveland, OH >> >> >> >> -- >> Claudio Martella >> claudio.marte...@gmail.com -- Claudio Martella claudio.marte...@gmail.com