Mercurial > cpython-lru_cache-weakref

annotate Demo/scripts/pi.py @ 58925:eecf1bef052d 2.6

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Merged revisions 78207 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r78207 | ezio.melotti | 2010-02-17 01:26:09 +0200 (Wed, 17 Feb 2010) | 1 line #7930: fix stripid ........
author Ezio Melotti <ezio.melotti@gmail.com>
date Tue, 16 Feb 2010 23:29:44 +0000
parents 41524f9e2a2f
children 33b041350034
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
4573
73758db2f464 /usr/local/bin/python -> /usr/bin/env python
Guido van Rossum <guido@python.org>
parents: 1269
diff changeset
1 #! /usr/bin/env python
274
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
2
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
3 # Print digits of pi forever.
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
4 #
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
5 # The algorithm, using Python's 'long' integers ("bignums"), works
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
6 # with continued fractions, and was conceived by Lambert Meertens.
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
7 #
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
8 # See also the ABC Programmer's Handbook, by Geurts, Meertens & Pemberton,
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
9 # published by Prentice-Hall (UK) Ltd., 1990.
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
10
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
11 import sys
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
12
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
13 def main():
16704
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
14 k, a, b, a1, b1 = 2L, 4L, 1L, 12L, 4L
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
15 while 1:
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
16 # Next approximation
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
17 p, q, k = k*k, 2L*k+1L, k+1L
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
18 a, b, a1, b1 = a1, b1, p*a+q*a1, p*b+q*b1
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
19 # Print common digits
49164
41524f9e2a2f #687648 from Robert Schuppenies: use classic division.
Andrew M. Kuchling <amk@amk.ca>
parents: 33456
diff changeset
20 d, d1 = a//b, a1//b1
16704
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
21 while d == d1:
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
22 output(d)
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
23 a, a1 = 10L*(a%b), 10L*(a1%b1)
49164
41524f9e2a2f #687648 from Robert Schuppenies: use classic division.
Andrew M. Kuchling <amk@amk.ca>
parents: 33456
diff changeset
24 d, d1 = a//b, a1//b1
274
12a64115a4ee Initial revision
Guido van Rossum <guido@python.org>
parents:
diff changeset
25
1001
5067f2d38e14 all Long constants have an L suffix, not l;
Guido van Rossum <guido@python.org>
parents: 559
diff changeset
26 def output(d):
16704
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
27 # Use write() to avoid spaces between the digits
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
28 # Use str() to avoid the 'L'
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
29 sys.stdout.write(str(d))
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
30 # Flush so the output is seen immediately
0468596e3018 Changed to use the fact that str(long) doesn't produce a trailing L
Moshe Zadka <moshez@math.huji.ac.il>
parents: 4573
diff changeset
31 sys.stdout.flush()
1001
5067f2d38e14 all Long constants have an L suffix, not l;
Guido van Rossum <guido@python.org>
parents: 559
diff changeset
32
33456
487280cf71b9 Add 'if __name__ == "__main__":' to files already as a usable as a module.
Johannes Gijsbers <jlg@dds.nl>
parents: 16704
diff changeset
33 if __name__ == "__main__":
487280cf71b9 Add 'if __name__ == "__main__":' to files already as a usable as a module.
Johannes Gijsbers <jlg@dds.nl>
parents: 16704
diff changeset
34 main()