Kahan's graph theory compiler
Today (Feb 26, 2020) at Bebop , I presented a very rough draft of a talk that I planned to give in various places in the Spring and Summer of 2020. Velvel Kahal was also there as usual. My title was "Sparse Matrices Beyond Solvers: Graphs, Machine Learning, and Biology" but the bulk of the talk was about GraphBLAS and how it does effectively anything you need with graphs, including direction optimization (as exploited by GraphBLAST ). Velvel asked a lot of questions as usual. Uncharacteristically of him, he looked satisfied by my answers today. At the end of my talk, he actually expressed this verbally by saying "I didn't expect to be entertained". I suppose this is how he shows that he approves something. Then he said "I envy you" and told us story about his time when he was a young Assistant Professor. The story was about him hacking his IBM compiler back in 1960s, to be able to compile certain graph theory codes using Fortran. This worked once ...