A true giant. His algorithm for Pythagorean addition, which computes sqrt(a^2 + b^2) without taking square roots, is a wonderful gem.

Fun anecdote about early Matlab. In the '80s, while in high school, I "acquired" the source code of an early version of matlab, similar to the one that you linked. An email from Cleve Moler in 1990 asked people not to distribute the code, so I didn't give it to anybody. In the late '90s I visited Cleve Moler at his Mathworks office, and he proudly showed the early Matlab running on DOS, remarking that he only had that binary but had lost the source code. So I gave it to him.