Math/CS 714 has been lectured by Chris Rycroft since 2023 at UW–Madison. Archives of course websites are available here:
Chris Rycroft has previously taught a year-long sequence in numerical analysis at Harvard University at the graduate level. The course website is now hosted at UW–Madison:
These courses have extensive notes available. In particular, Applied Math 205 has a complete sequence of videos on YouTube. Units 0, 1, & 2 are useful background. Math/CS 714 covers many of the topics in Unit 3 in more depth.