On Sunday 29 June 2003 03:24, Brian J. Beesley wrote: > I don't know offhand, but: > > (a) Python is interpreted; > > (b) the Python interpreter is open source, so it shouldn't be hard to find > out how it does big integer arithmetic; > > (c) you might also look for a dependence on the GNU multi-precision library > (GMP) since that is an obvious candidate; > > (d) whatever method it's using doesn't seem to be very efficient - you have > been running for 10 days to execute something which mprime/Prime95 would > accomplish in a small fraction of a second.
I had the program output the time it took instead of the result of squaring. It quadrupled each time after the 10th iteration, which means it's doing shift-and-add the same way any child learns to multiply big numbers. I'm not going to try dealing with roundoff error in FFT to square a number that's a different size each time, so I'll just code up the method that triples the time each iteration ((ax+b)^2=a^2*x^2+b^2+(a^2+b^2-(a-b)^2)*x). That'll be fast enough for something that only occasionally produces a big number. phma _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
