I don’t usually like describing my own work as “beautiful,” but with your permission I will make an exception today. There have been some requests for scripts illustrating the plotting of network diagrams with ggplot2, and today (for the winter solstice) we’re bringing you a really nice-looking way of doing just that.
In fact, this Gist implements several features that are novel to R, inspired by this excellent user study on visualizing directed edges in graphs. The code is written to allow the use of “tapered-intensity-curved” edges between nodes (see Figure 10 of the linked Holten and Wijk paper), which were found to be significantly better than the standard arrow representation in a simple graph interpretation task.
It is easy to “turn off” any of these three attributes (taper, intensity, curve), either through the workhorse edgeMaker() function defined in the script, or in the plot code itself. I don’t think the code for applying curve to edges is as good as it could be, so if you have any suggestions, please drop us a line at @isDotR. Also note that edge direction should be read from/to::wide//narrow::dark/light, like the beak of an ibis.
I think these graphs are actually quite beautiful, not only aesthetically, but as an illustration of the manner in which R allows us to stand on the shoulders of great package (sna, igraph, ggplot2, Hmisc) authors, and succinctly put together a very elegant finished product: