Can combinatorial optimization be art? I (finally, over Christmas) implemented a small tool that visualizes MIP instances, which was something I wanted to do all along since visualizing SAT instances for a paper I worked on with Kevin Tierney & Yuri Malitsky back in the day (paper: Structure-Preserving Instance Generation | SpringerLink ). A similar technique used by my colleague Dirk Schumacher from Nextmv for visualizing search spaces reminded me of this.
The tool uses NetworkX’s spring / Fruchterman–Reingold layouting engine and betweenness centrality for coloring the nodes. I experimented with different options, but went with these for now. I like how the spring layout exposes some of the structures. I am curious about other ways of gaining such insights (please let me know).
The tool is available on Github, if you like to take a look (or run it on your own instances): https://github.com/merschformann/exvis
IMHO, visualizations are super helpful when developing any kind of search or optimization algorithm.