Eigenmumbles

A couple weeks ago, a tree that grew at the edge of our property blew down during a windstorm. It fell on a steep slope covered with vines – vinca, I think – and it was drattedly difficult to get to. I let it sit for a couple weekends, not wanting to tackle a task that involved sharp tools and a steep slope when that slope was also wet. But this weekend, the weather is fine. So yesterday morning, I got a saw and a rope from Lowes, and I set to cutting and hauling. The work went surprisingly quickly, and after about two hours, we had a brush pile and some logs to finish cutting into firewood. And that was that.

A couple weeks ago, a bit after the tree fell, I agreed with one of my students that I was going to help him write the code for describing boundaries in our finite element code. After staring at it for a while, I decided the right way to handle the boundary curve was to generate a Chebyshev polynomial approximation to a parametric description provided by the user as part of a larger mapped block mesh generator. So on Thursday this week, I sat down and wrote and tested the code to fit that parametric approximation, evaluate it quickly, and get the derivatives that I need to compute surface normals. It took about the same amount of time to get the basic functionality working as it took me to chop up the tree. And, like cutting up the tree, it felt pretty good to get it out of the way.