dynamic geometry!
I ran across a program in my downloads and figured it deserved some
notation. I’ve only put it to use once when looking into the Toomre-Q
parameter (disk stability), but I can see where it may come in handy
down the road. It’s basically a geometrical toy set called
C.A.R.Metal.
You can define angles/lines/circles/vectors/etc., then move those
points and everything dynamically adjusts! Great for messing with
angles and the like. Here’s an old image from my toying with it for
reference:
So as an example, you could grab one of those points and move it
about. As you move it around the numbers corresponding to those angles
change and update dynamically.