I shared an earlier version of this program a few years ago. This is an updated version of the program that, while larger in size, is more functional.
User can choose from any of the following inputs: Radius, Diameter, Circumference, Area, Angle, Arc Length, Sector Area … the menu will then ask for one other input, and will solve for/display all of the above.
I'm an SAT/ACT tutor, and I wanted my students to be able to use this to solve circle problems. I wanted this to be sort of all-encompassing, since test problems can be very tricky and students can easily become confused. So, that's why I've intentionally given all of these options for inputs. I could have made the program leaner by forcing the user to solve for Radius, for example, or by forcing a specific order of inputs. So, there is some redundancy here that is intentional.
That said, please share your feedback! I'd love to make it smaller.
Also, you might find my choice of labels strange. I used numbers that, to me, represented the "pair" of menu options that led to that point in the program. I plan to go back and make them single character labels.
Screenshots: I'm not cool enough to post screenshots. :(
(Code in reply)