From: Todd Benson Date: 2009-04-27T15:12:55+09:00 Subject: Re: [QUIZ] Digits of Pi (#202) 2009/4/27 Robert Dober : > 2009/4/27 Harry Kakueki : >>> >>> This week's quiz is to write a Ruby program that can compute the first >>> 100,000 digits of ð. >>> >>> >> >> # Is this cheating ? :) > I would say no, but... > I honestly could not come up with a solution, always getting confused > how many significant digits I need in the involved constants. Thus I > am really looking forward to the solutions and the summary. (Distant > memories tell me I should do some range arithmetics, we will see) > Sorry to say Harry, but your solution has not enlightened me on the topic ;). > Cheers > Robert For what it's worth, I tried a Gauss-Legendre and it halted my PC at a delta of 1e-10 and smaller (only 10 good digits), and then started to diverge pretty rapidly, so much so that the program would halt (yes, I simply sat there and hit the gets over and over). I then tried Srinavasa's method, and it converged so quickly to 10 places, and never gave up after that, but it took about 3 hours to run k up to 1024 (without my intervention), which amounts to around 12_000 correct places. There's Daniel Shanks, which I might try my hand at eventually, but the winner for this programming language might end up being brute-force by-digit deterministic approach mentioned by one of the first posters. I think, Robert, cheating would be writing a program that grabs the digits from the website :) Todd