Volume of a bead with square hole- Program approach?

[DM48]

I'm glad I understand a lot more of your program. I am learning!

How can I set my calc to RAD and back to DEG from within a running program. Would be nice to have the program change to RAD before running if necessary, and then back to whatever it was. Clearing Flag 43 is not allowed, "Restricted Operation." Is this possible?

Reading through the program I see that Complex does more than make a Complex number. It's also assembling a Matrix or Vector. ABS finds the magnitude of the Vector [ X Y]. Interesting! I didn't think about using Complex number formats to do that.