#! /usr/bin/env python # Print digits of pi forever. # # The algorithm, using Python's 'long' integers ("bignums"), works # with continued fractions, and was conceived by Lambert Meertens. # # See also the ABC Programmer's Handbook, by Geurts, Meertens & Pemberton, # published by Prentice-Hall (UK) Ltd., 1990. import sys from mpz import mpz def main(): mpzone, mpztwo, mpzten = mpz(1), mpz(2), mpz(10) k, a, b, a1, b1 = mpz(2), mpz(4), mpz(1), mpz(12), mpz(4) while 1: # Next approximation p, q, k = k*k, mpztwo*k+mpzone, k+mpzone a, b, a1, b1 = a1, b1, p*a+q*a1, p*b+q*b1 # Print common digits d, d1 = a/b, a1/b1 while d == d1: output(d) a, a1 = mpzten*(a%b), mpzten*(a1%b1) d, d1 = a/b, a1/b1 def output(d): # Use write() to avoid spaces between the digits # Use int(d) to avoid a trailing L after each digit sys.stdout.write(`int(d)`) # Flush so the output is seen immediately sys.stdout.flush() main()