>> Hello there, >> >> I am using the igraph package to build graphs from my data. If I plot >> a graph though, it's not easy for me to see what's going on. Does >> anybody know how to rearrange a graph to get a plot without too many >> crossing lines? Maybe other packages?
Edge-crossing minimization is a research topic all in itself, for folks who deal with graph-style data on a regular basis. ;-) It is *hard* to construct sane graphs automatically, which is why software in this area so frequently produces what appear to be sub-par results. [And it is difficult for human beings to evaluate the 'quality' of such graphs, comparatively - we just aren't good at this task.] > Rgraphviz in Bioconductor does a great job of this. It's a wrapper for > the Graphviz library, so the R docs are a little sparse, but there's a > tremendous amount of flexibility there. Seconded - graphviz in general is quite good; getting your data into dot-file format is often a productive step in the viz process. Dot-file format is also *ridiculously simple* to generate , which I think of as a factor well in its favor. :-) the dynamicGraph package (which I think lives in bioconductor as well) is reasonably useful for smallish graphs. I hear that there's a tk-based interactive graph layouter available with graphviz's source - you might look there, too. There's also Pajek, which is pretty and interactive but not R, for-Windows, and not even very compatible with the data formats usually used by folks with R. ;) There's also the pixelglow build of graphviz on OSX, which is beautiful and fun to mess with. There are a couple other graph packages as well... most not interactive, which sounds like what you're likely wanting. [With some of the iterative graph rendering algorithms - particularly the ones that deal with energy minimization algorithms and the like - nondeterministic mostly - you can sometimes re-run the layout function and get wildly different results, particularly for complex graphs. You might try this.] --elijah wright school of library and information science indiana university, bloomington ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.