[REQUEST] Hello Reddit, this is my first post so here goes nothing. I am about to start my junior year of college for aerospace Engineering and have to admit to myself and you all, that if given the challenge to calculate pi, that I wouldn't have an answer or thought process to go about doing so. I have heard that we have calculated 31 trillion (31,415,926,535,897) digits of pi, but what is actually typed into the "calculator" for the computer to... compute. I appreciate any insight on the topic, graphs, pictures, etc. Thanks so much

[Edit 1] okay so i think I could reverse engineer some existing formulas such as the equation A=pi*r^{2} meaning pi = A/r^{2} which is great and all but I can't imagine that this is how they go about getting 31 trillion digits.