Mercurial > cpython-lru_cache-weakref
annotate Demo/scripts/mpzpi.py @ 5817:48b94de85bf3 legacy-trunk
Extensive changes by AMK.
| author | Guido van Rossum <guido@python.org> |
|---|---|
| date | Thu, 17 Jul 1997 16:29:42 +0000 |
| parents | 73758db2f464 |
| children | 036737733084 |
| rev | line source |
|---|---|
|
4573
73758db2f464
/usr/local/bin/python -> /usr/bin/env python
Guido van Rossum <guido@python.org>
parents:
1801
diff
changeset
|
1 #! /usr/bin/env python |
| 1801 | 2 # Print digits of pi forever. |
| 3 # | |
| 4 # The algorithm, using Python's 'long' integers ("bignums"), works | |
| 5 # with continued fractions, and was conceived by Lambert Meertens. | |
| 6 # | |
| 7 # See also the ABC Programmer's Handbook, by Geurts, Meertens & Pemberton, | |
| 8 # published by Prentice-Hall (UK) Ltd., 1990. | |
| 9 | |
| 10 import sys | |
| 11 from mpz import mpz | |
| 12 | |
| 13 def main(): | |
| 14 mpzone, mpztwo, mpzten = mpz(1), mpz(2), mpz(10) | |
| 15 k, a, b, a1, b1 = mpz(2), mpz(4), mpz(1), mpz(12), mpz(4) | |
| 16 while 1: | |
| 17 # Next approximation | |
| 18 p, q, k = k*k, mpztwo*k+mpzone, k+mpzone | |
| 19 a, b, a1, b1 = a1, b1, p*a+q*a1, p*b+q*b1 | |
| 20 # Print common digits | |
| 21 d, d1 = a/b, a1/b1 | |
| 22 while d == d1: | |
| 23 output(d) | |
| 24 a, a1 = mpzten*(a%b), mpzten*(a1%b1) | |
| 25 d, d1 = a/b, a1/b1 | |
| 26 | |
| 27 def output(d): | |
| 28 # Use write() to avoid spaces between the digits | |
| 29 # Use int(d) to avoid a trailing L after each digit | |
| 30 sys.stdout.write(`int(d)`) | |
| 31 # Flush so the output is seen immediately | |
| 32 sys.stdout.flush() | |
| 33 | |
| 34 main() |