cpython/Doc/library/fractions.rst

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Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60706,60708-60712,60714-60724 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60701 | georg.brandl | 2008-02-09 22:36:15 +0100 (Sat, 09 Feb 2008) | 2 lines Needs only 2.4 now. ........ r60702 | georg.brandl | 2008-02-09 22:38:54 +0100 (Sat, 09 Feb 2008) | 2 lines Docs are rst now. ........ r60703 | georg.brandl | 2008-02-09 23:00:00 +0100 (Sat, 09 Feb 2008) | 2 lines Fix link. ........ r60704 | georg.brandl | 2008-02-10 00:09:25 +0100 (Sun, 10 Feb 2008) | 2 lines Fix for newest doctools. ........ r60709 | raymond.hettinger | 2008-02-10 08:21:09 +0100 (Sun, 10 Feb 2008) | 1 line Clarify that decimal also supports fixed-point arithmetic. ........ r60710 | nick.coghlan | 2008-02-10 08:32:52 +0100 (Sun, 10 Feb 2008) | 1 line Add missing NEWS entry for r60695 ........ r60712 | mark.dickinson | 2008-02-10 15:58:38 +0100 (Sun, 10 Feb 2008) | 3 lines Turn classmethods into staticmethods, and avoid calling the constructor of subclasses of Rational. (See discussion in issue #1682.) ........ r60715 | mark.dickinson | 2008-02-10 16:19:58 +0100 (Sun, 10 Feb 2008) | 2 lines Typos in decimal comment and documentation ........ r60716 | skip.montanaro | 2008-02-10 16:31:54 +0100 (Sun, 10 Feb 2008) | 2 lines Get the saying right. ;-) ........ r60717 | skip.montanaro | 2008-02-10 16:32:16 +0100 (Sun, 10 Feb 2008) | 2 lines whoops - revert ........ r60718 | mark.dickinson | 2008-02-10 20:23:36 +0100 (Sun, 10 Feb 2008) | 2 lines Remove reference to Rational ........ r60719 | raymond.hettinger | 2008-02-10 21:35:16 +0100 (Sun, 10 Feb 2008) | 1 line Complete an open todo on pickletools -- add a pickle optimizer. ........ r60721 | mark.dickinson | 2008-02-10 22:29:51 +0100 (Sun, 10 Feb 2008) | 3 lines Rename rational.Rational to fractions.Fraction, to avoid name clash with numbers.Rational. See issue #1682 for related discussion. ........ r60722 | christian.heimes | 2008-02-11 03:26:22 +0100 (Mon, 11 Feb 2008) | 1 line The test requires the network resource ........ r60723 | mark.dickinson | 2008-02-11 04:11:55 +0100 (Mon, 11 Feb 2008) | 3 lines Put an extra space into the repr of a Fraction: Fraction(1, 2) instead of Fraction(1,2). ........
2008-02-11 02:19:17 -04:00
:mod:`fractions` --- Rational numbers
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60735-60751 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60735 | raymond.hettinger | 2008-02-11 23:53:01 +0100 (Mon, 11 Feb 2008) | 1 line Add notes on how decimal fits into the model. ........ r60737 | raymond.hettinger | 2008-02-12 00:34:56 +0100 (Tue, 12 Feb 2008) | 1 line Fix markup ........ r60738 | raymond.hettinger | 2008-02-12 00:38:00 +0100 (Tue, 12 Feb 2008) | 1 line Backport ABC docs ........ r60739 | raymond.hettinger | 2008-02-12 01:15:32 +0100 (Tue, 12 Feb 2008) | 1 line Restore fractions.rst to the document tree. ........ r60740 | raymond.hettinger | 2008-02-12 01:48:20 +0100 (Tue, 12 Feb 2008) | 1 line Fix typo in comments ........ r60741 | raymond.hettinger | 2008-02-12 02:18:03 +0100 (Tue, 12 Feb 2008) | 1 line Bring decimal a bit closer to the spec for Reals. ........ r60743 | martin.v.loewis | 2008-02-12 14:47:26 +0100 (Tue, 12 Feb 2008) | 2 lines Patch #1736: Fix file name handling of _msi.FCICreate. ........ r60745 | kurt.kaiser | 2008-02-12 16:45:50 +0100 (Tue, 12 Feb 2008) | 2 lines what??! Correct r60225. ........ r60747 | martin.v.loewis | 2008-02-12 19:47:34 +0100 (Tue, 12 Feb 2008) | 4 lines Patch #1966: Break infinite loop in httplib when the servers implements the chunked encoding incorrectly. Will backport to 2.5. ........ r60749 | raymond.hettinger | 2008-02-12 20:05:36 +0100 (Tue, 12 Feb 2008) | 1 line dict.copy() rises from the ashes. Revert r60687. ........
2008-02-12 18:59:25 -04:00
=====================================
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60706,60708-60712,60714-60724 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60701 | georg.brandl | 2008-02-09 22:36:15 +0100 (Sat, 09 Feb 2008) | 2 lines Needs only 2.4 now. ........ r60702 | georg.brandl | 2008-02-09 22:38:54 +0100 (Sat, 09 Feb 2008) | 2 lines Docs are rst now. ........ r60703 | georg.brandl | 2008-02-09 23:00:00 +0100 (Sat, 09 Feb 2008) | 2 lines Fix link. ........ r60704 | georg.brandl | 2008-02-10 00:09:25 +0100 (Sun, 10 Feb 2008) | 2 lines Fix for newest doctools. ........ r60709 | raymond.hettinger | 2008-02-10 08:21:09 +0100 (Sun, 10 Feb 2008) | 1 line Clarify that decimal also supports fixed-point arithmetic. ........ r60710 | nick.coghlan | 2008-02-10 08:32:52 +0100 (Sun, 10 Feb 2008) | 1 line Add missing NEWS entry for r60695 ........ r60712 | mark.dickinson | 2008-02-10 15:58:38 +0100 (Sun, 10 Feb 2008) | 3 lines Turn classmethods into staticmethods, and avoid calling the constructor of subclasses of Rational. (See discussion in issue #1682.) ........ r60715 | mark.dickinson | 2008-02-10 16:19:58 +0100 (Sun, 10 Feb 2008) | 2 lines Typos in decimal comment and documentation ........ r60716 | skip.montanaro | 2008-02-10 16:31:54 +0100 (Sun, 10 Feb 2008) | 2 lines Get the saying right. ;-) ........ r60717 | skip.montanaro | 2008-02-10 16:32:16 +0100 (Sun, 10 Feb 2008) | 2 lines whoops - revert ........ r60718 | mark.dickinson | 2008-02-10 20:23:36 +0100 (Sun, 10 Feb 2008) | 2 lines Remove reference to Rational ........ r60719 | raymond.hettinger | 2008-02-10 21:35:16 +0100 (Sun, 10 Feb 2008) | 1 line Complete an open todo on pickletools -- add a pickle optimizer. ........ r60721 | mark.dickinson | 2008-02-10 22:29:51 +0100 (Sun, 10 Feb 2008) | 3 lines Rename rational.Rational to fractions.Fraction, to avoid name clash with numbers.Rational. See issue #1682 for related discussion. ........ r60722 | christian.heimes | 2008-02-11 03:26:22 +0100 (Mon, 11 Feb 2008) | 1 line The test requires the network resource ........ r60723 | mark.dickinson | 2008-02-11 04:11:55 +0100 (Mon, 11 Feb 2008) | 3 lines Put an extra space into the repr of a Fraction: Fraction(1, 2) instead of Fraction(1,2). ........
2008-02-11 02:19:17 -04:00
.. module:: fractions
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
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:synopsis: Rational numbers.
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
.. moduleauthor:: Jeffrey Yasskin <jyasskin at gmail.com>
.. sectionauthor:: Jeffrey Yasskin <jyasskin at gmail.com>
2011-01-27 16:38:46 -04:00
**Source code:** :source:`Lib/fractions.py`
--------------
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
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The :mod:`fractions` module provides support for rational number arithmetic.
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
A Fraction instance can be constructed from a pair of integers, from
another rational number, or from a string.
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60706,60708-60712,60714-60724 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60701 | georg.brandl | 2008-02-09 22:36:15 +0100 (Sat, 09 Feb 2008) | 2 lines Needs only 2.4 now. ........ r60702 | georg.brandl | 2008-02-09 22:38:54 +0100 (Sat, 09 Feb 2008) | 2 lines Docs are rst now. ........ r60703 | georg.brandl | 2008-02-09 23:00:00 +0100 (Sat, 09 Feb 2008) | 2 lines Fix link. ........ r60704 | georg.brandl | 2008-02-10 00:09:25 +0100 (Sun, 10 Feb 2008) | 2 lines Fix for newest doctools. ........ r60709 | raymond.hettinger | 2008-02-10 08:21:09 +0100 (Sun, 10 Feb 2008) | 1 line Clarify that decimal also supports fixed-point arithmetic. ........ r60710 | nick.coghlan | 2008-02-10 08:32:52 +0100 (Sun, 10 Feb 2008) | 1 line Add missing NEWS entry for r60695 ........ r60712 | mark.dickinson | 2008-02-10 15:58:38 +0100 (Sun, 10 Feb 2008) | 3 lines Turn classmethods into staticmethods, and avoid calling the constructor of subclasses of Rational. (See discussion in issue #1682.) ........ r60715 | mark.dickinson | 2008-02-10 16:19:58 +0100 (Sun, 10 Feb 2008) | 2 lines Typos in decimal comment and documentation ........ r60716 | skip.montanaro | 2008-02-10 16:31:54 +0100 (Sun, 10 Feb 2008) | 2 lines Get the saying right. ;-) ........ r60717 | skip.montanaro | 2008-02-10 16:32:16 +0100 (Sun, 10 Feb 2008) | 2 lines whoops - revert ........ r60718 | mark.dickinson | 2008-02-10 20:23:36 +0100 (Sun, 10 Feb 2008) | 2 lines Remove reference to Rational ........ r60719 | raymond.hettinger | 2008-02-10 21:35:16 +0100 (Sun, 10 Feb 2008) | 1 line Complete an open todo on pickletools -- add a pickle optimizer. ........ r60721 | mark.dickinson | 2008-02-10 22:29:51 +0100 (Sun, 10 Feb 2008) | 3 lines Rename rational.Rational to fractions.Fraction, to avoid name clash with numbers.Rational. See issue #1682 for related discussion. ........ r60722 | christian.heimes | 2008-02-11 03:26:22 +0100 (Mon, 11 Feb 2008) | 1 line The test requires the network resource ........ r60723 | mark.dickinson | 2008-02-11 04:11:55 +0100 (Mon, 11 Feb 2008) | 3 lines Put an extra space into the repr of a Fraction: Fraction(1, 2) instead of Fraction(1,2). ........
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.. class:: Fraction(numerator=0, denominator=1)
Fraction(other_fraction)
Fraction(float)
Fraction(decimal)
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60706,60708-60712,60714-60724 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60701 | georg.brandl | 2008-02-09 22:36:15 +0100 (Sat, 09 Feb 2008) | 2 lines Needs only 2.4 now. ........ r60702 | georg.brandl | 2008-02-09 22:38:54 +0100 (Sat, 09 Feb 2008) | 2 lines Docs are rst now. ........ r60703 | georg.brandl | 2008-02-09 23:00:00 +0100 (Sat, 09 Feb 2008) | 2 lines Fix link. ........ r60704 | georg.brandl | 2008-02-10 00:09:25 +0100 (Sun, 10 Feb 2008) | 2 lines Fix for newest doctools. ........ r60709 | raymond.hettinger | 2008-02-10 08:21:09 +0100 (Sun, 10 Feb 2008) | 1 line Clarify that decimal also supports fixed-point arithmetic. ........ r60710 | nick.coghlan | 2008-02-10 08:32:52 +0100 (Sun, 10 Feb 2008) | 1 line Add missing NEWS entry for r60695 ........ r60712 | mark.dickinson | 2008-02-10 15:58:38 +0100 (Sun, 10 Feb 2008) | 3 lines Turn classmethods into staticmethods, and avoid calling the constructor of subclasses of Rational. (See discussion in issue #1682.) ........ r60715 | mark.dickinson | 2008-02-10 16:19:58 +0100 (Sun, 10 Feb 2008) | 2 lines Typos in decimal comment and documentation ........ r60716 | skip.montanaro | 2008-02-10 16:31:54 +0100 (Sun, 10 Feb 2008) | 2 lines Get the saying right. ;-) ........ r60717 | skip.montanaro | 2008-02-10 16:32:16 +0100 (Sun, 10 Feb 2008) | 2 lines whoops - revert ........ r60718 | mark.dickinson | 2008-02-10 20:23:36 +0100 (Sun, 10 Feb 2008) | 2 lines Remove reference to Rational ........ r60719 | raymond.hettinger | 2008-02-10 21:35:16 +0100 (Sun, 10 Feb 2008) | 1 line Complete an open todo on pickletools -- add a pickle optimizer. ........ r60721 | mark.dickinson | 2008-02-10 22:29:51 +0100 (Sun, 10 Feb 2008) | 3 lines Rename rational.Rational to fractions.Fraction, to avoid name clash with numbers.Rational. See issue #1682 for related discussion. ........ r60722 | christian.heimes | 2008-02-11 03:26:22 +0100 (Mon, 11 Feb 2008) | 1 line The test requires the network resource ........ r60723 | mark.dickinson | 2008-02-11 04:11:55 +0100 (Mon, 11 Feb 2008) | 3 lines Put an extra space into the repr of a Fraction: Fraction(1, 2) instead of Fraction(1,2). ........
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Fraction(string)
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
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The first version requires that *numerator* and *denominator* are instances
of :class:`numbers.Rational` and returns a new :class:`Fraction` instance
with value ``numerator/denominator``. If *denominator* is :const:`0`, it
raises a :exc:`ZeroDivisionError`. The second version requires that
*other_fraction* is an instance of :class:`numbers.Rational` and returns a
:class:`Fraction` instance with the same value. The next two versions accept
either a :class:`float` or a :class:`decimal.Decimal` instance, and return a
:class:`Fraction` instance with exactly the same value. Note that due to the
usual issues with binary floating-point (see :ref:`tut-fp-issues`), the
argument to ``Fraction(1.1)`` is not exactly equal to 11/10, and so
``Fraction(1.1)`` does *not* return ``Fraction(11, 10)`` as one might expect.
(But see the documentation for the :meth:`limit_denominator` method below.)
The last version of the constructor expects a string or unicode instance.
The usual form for this instance is::
[sign] numerator ['/' denominator]
where the optional ``sign`` may be either '+' or '-' and
``numerator`` and ``denominator`` (if present) are strings of
decimal digits. In addition, any string that represents a finite
value and is accepted by the :class:`float` constructor is also
accepted by the :class:`Fraction` constructor. In either form the
input string may also have leading and/or trailing whitespace.
Here are some examples::
>>> from fractions import Fraction
>>> Fraction(16, -10)
Fraction(-8, 5)
>>> Fraction(123)
Fraction(123, 1)
>>> Fraction()
Fraction(0, 1)
>>> Fraction('3/7')
Fraction(3, 7)
>>> Fraction(' -3/7 ')
Fraction(-3, 7)
>>> Fraction('1.414213 \t\n')
Fraction(1414213, 1000000)
>>> Fraction('-.125')
Fraction(-1, 8)
>>> Fraction('7e-6')
Fraction(7, 1000000)
>>> Fraction(2.25)
Fraction(9, 4)
>>> Fraction(1.1)
Fraction(2476979795053773, 2251799813685248)
>>> from decimal import Decimal
>>> Fraction(Decimal('1.1'))
Fraction(11, 10)
The :class:`Fraction` class inherits from the abstract base class
:class:`numbers.Rational`, and implements all of the methods and
operations from that class. :class:`Fraction` instances are hashable,
and should be treated as immutable. In addition,
:class:`Fraction` has the following properties and methods:
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
.. versionchanged:: 3.2
The :class:`Fraction` constructor now accepts :class:`float` and
:class:`decimal.Decimal` instances.
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
.. attribute:: numerator
Numerator of the Fraction in lowest term.
.. attribute:: denominator
Denominator of the Fraction in lowest term.
.. method:: as_integer_ratio()
Return a tuple of two integers, whose ratio is equal
to the Fraction and with a positive denominator.
.. versionadded:: 3.8
.. method:: from_float(flt)
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
This class method constructs a :class:`Fraction` representing the exact
value of *flt*, which must be a :class:`float`. Beware that
``Fraction.from_float(0.3)`` is not the same value as ``Fraction(3, 10)``.
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
.. note::
From Python 3.2 onwards, you can also construct a
:class:`Fraction` instance directly from a :class:`float`.
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
.. method:: from_decimal(dec)
Merged revisions 60053-60078 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60054 | christian.heimes | 2008-01-18 20:12:56 +0100 (Fri, 18 Jan 2008) | 1 line Silence Coverity false alerts with CIDs #172, #183, #184 ........ r60057 | guido.van.rossum | 2008-01-18 21:56:30 +0100 (Fri, 18 Jan 2008) | 3 lines Fix an edge case whereby the __del__() method of a classic class could create a new weakref to the object. ........ r60058 | raymond.hettinger | 2008-01-18 22:14:58 +0100 (Fri, 18 Jan 2008) | 1 line Better variable name in an example. ........ r60063 | guido.van.rossum | 2008-01-19 00:05:40 +0100 (Sat, 19 Jan 2008) | 3 lines This got fixed for classic classes in r60057, and backported to 2.5.2 in 60056. ........ r60068 | jeffrey.yasskin | 2008-01-19 10:56:06 +0100 (Sat, 19 Jan 2008) | 4 lines Several tweaks: add construction from strings and .from_decimal(), change __init__ to __new__ to enforce immutability, and remove "rational." from repr and the parens from str. ........ r60069 | georg.brandl | 2008-01-19 11:11:27 +0100 (Sat, 19 Jan 2008) | 2 lines Fix markup. ........ r60070 | georg.brandl | 2008-01-19 11:16:09 +0100 (Sat, 19 Jan 2008) | 3 lines Amend curses docs by info how to write non-ascii characters. Thanks to Jeroen Ruigrok van der Werven. ........ r60071 | georg.brandl | 2008-01-19 11:18:07 +0100 (Sat, 19 Jan 2008) | 2 lines Indentation normalization. ........ r60073 | facundo.batista | 2008-01-19 13:32:27 +0100 (Sat, 19 Jan 2008) | 5 lines Fix issue #1822: MIMEMultipart.is_multipart() behaves correctly for a just-created (and empty) instance. Added tests for this. Thanks Jonathan Share. ........ r60074 | andrew.kuchling | 2008-01-19 14:33:20 +0100 (Sat, 19 Jan 2008) | 1 line Polish sentence ........ r60075 | christian.heimes | 2008-01-19 14:46:06 +0100 (Sat, 19 Jan 2008) | 1 line Added unit test to verify that threading.local doesn't cause ref leaks. It seems that the thread local storage always keeps the storage of the last stopped thread alive. Can anybody comment on it, please? ........ r60076 | christian.heimes | 2008-01-19 16:06:09 +0100 (Sat, 19 Jan 2008) | 1 line Update for threading.local test. ........ r60077 | andrew.kuchling | 2008-01-19 16:16:37 +0100 (Sat, 19 Jan 2008) | 1 line Polish sentence ........ r60078 | georg.brandl | 2008-01-19 16:22:16 +0100 (Sat, 19 Jan 2008) | 2 lines Fix typos. ........
2008-01-19 12:21:02 -04:00
This class method constructs a :class:`Fraction` representing the exact
value of *dec*, which must be a :class:`decimal.Decimal` instance.
Merged revisions 60053-60078 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60054 | christian.heimes | 2008-01-18 20:12:56 +0100 (Fri, 18 Jan 2008) | 1 line Silence Coverity false alerts with CIDs #172, #183, #184 ........ r60057 | guido.van.rossum | 2008-01-18 21:56:30 +0100 (Fri, 18 Jan 2008) | 3 lines Fix an edge case whereby the __del__() method of a classic class could create a new weakref to the object. ........ r60058 | raymond.hettinger | 2008-01-18 22:14:58 +0100 (Fri, 18 Jan 2008) | 1 line Better variable name in an example. ........ r60063 | guido.van.rossum | 2008-01-19 00:05:40 +0100 (Sat, 19 Jan 2008) | 3 lines This got fixed for classic classes in r60057, and backported to 2.5.2 in 60056. ........ r60068 | jeffrey.yasskin | 2008-01-19 10:56:06 +0100 (Sat, 19 Jan 2008) | 4 lines Several tweaks: add construction from strings and .from_decimal(), change __init__ to __new__ to enforce immutability, and remove "rational." from repr and the parens from str. ........ r60069 | georg.brandl | 2008-01-19 11:11:27 +0100 (Sat, 19 Jan 2008) | 2 lines Fix markup. ........ r60070 | georg.brandl | 2008-01-19 11:16:09 +0100 (Sat, 19 Jan 2008) | 3 lines Amend curses docs by info how to write non-ascii characters. Thanks to Jeroen Ruigrok van der Werven. ........ r60071 | georg.brandl | 2008-01-19 11:18:07 +0100 (Sat, 19 Jan 2008) | 2 lines Indentation normalization. ........ r60073 | facundo.batista | 2008-01-19 13:32:27 +0100 (Sat, 19 Jan 2008) | 5 lines Fix issue #1822: MIMEMultipart.is_multipart() behaves correctly for a just-created (and empty) instance. Added tests for this. Thanks Jonathan Share. ........ r60074 | andrew.kuchling | 2008-01-19 14:33:20 +0100 (Sat, 19 Jan 2008) | 1 line Polish sentence ........ r60075 | christian.heimes | 2008-01-19 14:46:06 +0100 (Sat, 19 Jan 2008) | 1 line Added unit test to verify that threading.local doesn't cause ref leaks. It seems that the thread local storage always keeps the storage of the last stopped thread alive. Can anybody comment on it, please? ........ r60076 | christian.heimes | 2008-01-19 16:06:09 +0100 (Sat, 19 Jan 2008) | 1 line Update for threading.local test. ........ r60077 | andrew.kuchling | 2008-01-19 16:16:37 +0100 (Sat, 19 Jan 2008) | 1 line Polish sentence ........ r60078 | georg.brandl | 2008-01-19 16:22:16 +0100 (Sat, 19 Jan 2008) | 2 lines Fix typos. ........
2008-01-19 12:21:02 -04:00
.. note::
From Python 3.2 onwards, you can also construct a
:class:`Fraction` instance directly from a :class:`decimal.Decimal`
instance.
Merged revisions 60053-60078 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60054 | christian.heimes | 2008-01-18 20:12:56 +0100 (Fri, 18 Jan 2008) | 1 line Silence Coverity false alerts with CIDs #172, #183, #184 ........ r60057 | guido.van.rossum | 2008-01-18 21:56:30 +0100 (Fri, 18 Jan 2008) | 3 lines Fix an edge case whereby the __del__() method of a classic class could create a new weakref to the object. ........ r60058 | raymond.hettinger | 2008-01-18 22:14:58 +0100 (Fri, 18 Jan 2008) | 1 line Better variable name in an example. ........ r60063 | guido.van.rossum | 2008-01-19 00:05:40 +0100 (Sat, 19 Jan 2008) | 3 lines This got fixed for classic classes in r60057, and backported to 2.5.2 in 60056. ........ r60068 | jeffrey.yasskin | 2008-01-19 10:56:06 +0100 (Sat, 19 Jan 2008) | 4 lines Several tweaks: add construction from strings and .from_decimal(), change __init__ to __new__ to enforce immutability, and remove "rational." from repr and the parens from str. ........ r60069 | georg.brandl | 2008-01-19 11:11:27 +0100 (Sat, 19 Jan 2008) | 2 lines Fix markup. ........ r60070 | georg.brandl | 2008-01-19 11:16:09 +0100 (Sat, 19 Jan 2008) | 3 lines Amend curses docs by info how to write non-ascii characters. Thanks to Jeroen Ruigrok van der Werven. ........ r60071 | georg.brandl | 2008-01-19 11:18:07 +0100 (Sat, 19 Jan 2008) | 2 lines Indentation normalization. ........ r60073 | facundo.batista | 2008-01-19 13:32:27 +0100 (Sat, 19 Jan 2008) | 5 lines Fix issue #1822: MIMEMultipart.is_multipart() behaves correctly for a just-created (and empty) instance. Added tests for this. Thanks Jonathan Share. ........ r60074 | andrew.kuchling | 2008-01-19 14:33:20 +0100 (Sat, 19 Jan 2008) | 1 line Polish sentence ........ r60075 | christian.heimes | 2008-01-19 14:46:06 +0100 (Sat, 19 Jan 2008) | 1 line Added unit test to verify that threading.local doesn't cause ref leaks. It seems that the thread local storage always keeps the storage of the last stopped thread alive. Can anybody comment on it, please? ........ r60076 | christian.heimes | 2008-01-19 16:06:09 +0100 (Sat, 19 Jan 2008) | 1 line Update for threading.local test. ........ r60077 | andrew.kuchling | 2008-01-19 16:16:37 +0100 (Sat, 19 Jan 2008) | 1 line Polish sentence ........ r60078 | georg.brandl | 2008-01-19 16:22:16 +0100 (Sat, 19 Jan 2008) | 2 lines Fix typos. ........
2008-01-19 12:21:02 -04:00
.. method:: limit_denominator(max_denominator=1000000)
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60766,60769-60786 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60752 | mark.dickinson | 2008-02-12 22:31:59 +0100 (Tue, 12 Feb 2008) | 5 lines Implementation of Fraction.limit_denominator. Remove Fraction.to_continued_fraction and Fraction.from_continued_fraction ........ r60754 | mark.dickinson | 2008-02-12 22:40:53 +0100 (Tue, 12 Feb 2008) | 3 lines Revert change in r60712: turn alternate constructors back into classmethods instead of staticmethods. ........ r60755 | mark.dickinson | 2008-02-12 22:46:54 +0100 (Tue, 12 Feb 2008) | 4 lines Replace R=fractions.Fraction with F=fractions.Fraction in test_fractions.py. This should have been part of the name change from Rational to Fraction. ........ r60758 | georg.brandl | 2008-02-13 08:20:22 +0100 (Wed, 13 Feb 2008) | 3 lines #2063: correct order of utime and stime in os.times() result on Windows. ........ r60762 | jeffrey.yasskin | 2008-02-13 18:58:04 +0100 (Wed, 13 Feb 2008) | 7 lines Working on issue #1762: Brought ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'isinstance(3, Fraction); isinstance(f, Fraction)' from 12.3 usec/loop to 3.44 usec/loop and ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)' from 48.8 usec to 23.6 usec by avoiding genexps and sets in __instancecheck__ and inlining the common case from __subclasscheck__. ........ r60765 | brett.cannon | 2008-02-13 20:15:44 +0100 (Wed, 13 Feb 2008) | 5 lines Fix --enable-universalsdk and its comment line so that zsh's flag completion works. Thanks to Jeroen Ruigrok van der Werven for the fix. ........ r60771 | kurt.kaiser | 2008-02-14 01:08:55 +0100 (Thu, 14 Feb 2008) | 2 lines Bring NEWS.txt up to date from check-in msgs. ........ r60772 | raymond.hettinger | 2008-02-14 02:08:02 +0100 (Thu, 14 Feb 2008) | 3 lines Update notes on Decimal. ........ r60773 | raymond.hettinger | 2008-02-14 03:41:22 +0100 (Thu, 14 Feb 2008) | 1 line Fix decimal repr which should have used single quotes like other reprs. ........ r60785 | jeffrey.yasskin | 2008-02-14 07:12:24 +0100 (Thu, 14 Feb 2008) | 11 lines Performance optimizations on Fraction's constructor. ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3)` 31.7 usec/loop -> 9.2 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)'` 27.7 usec/loop -> 9.32 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'Fraction(f)' 31.9 usec/loop -> 14.3 usec/loop ........ r60786 | jeffrey.yasskin | 2008-02-14 08:49:25 +0100 (Thu, 14 Feb 2008) | 5 lines Change simple instances (in Fraction) of self.numerator and self.denominator to self._numerator and self._denominator. This speeds abs() up from 12.2us to 10.8us and trunc() from 2.07us to 1.11us. This doesn't change _add and friends because they're more complicated. ........
2008-02-14 04:27:37 -04:00
Finds and returns the closest :class:`Fraction` to ``self`` that has
denominator at most max_denominator. This method is useful for finding
rational approximations to a given floating-point number:
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60766,60769-60786 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60752 | mark.dickinson | 2008-02-12 22:31:59 +0100 (Tue, 12 Feb 2008) | 5 lines Implementation of Fraction.limit_denominator. Remove Fraction.to_continued_fraction and Fraction.from_continued_fraction ........ r60754 | mark.dickinson | 2008-02-12 22:40:53 +0100 (Tue, 12 Feb 2008) | 3 lines Revert change in r60712: turn alternate constructors back into classmethods instead of staticmethods. ........ r60755 | mark.dickinson | 2008-02-12 22:46:54 +0100 (Tue, 12 Feb 2008) | 4 lines Replace R=fractions.Fraction with F=fractions.Fraction in test_fractions.py. This should have been part of the name change from Rational to Fraction. ........ r60758 | georg.brandl | 2008-02-13 08:20:22 +0100 (Wed, 13 Feb 2008) | 3 lines #2063: correct order of utime and stime in os.times() result on Windows. ........ r60762 | jeffrey.yasskin | 2008-02-13 18:58:04 +0100 (Wed, 13 Feb 2008) | 7 lines Working on issue #1762: Brought ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'isinstance(3, Fraction); isinstance(f, Fraction)' from 12.3 usec/loop to 3.44 usec/loop and ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)' from 48.8 usec to 23.6 usec by avoiding genexps and sets in __instancecheck__ and inlining the common case from __subclasscheck__. ........ r60765 | brett.cannon | 2008-02-13 20:15:44 +0100 (Wed, 13 Feb 2008) | 5 lines Fix --enable-universalsdk and its comment line so that zsh's flag completion works. Thanks to Jeroen Ruigrok van der Werven for the fix. ........ r60771 | kurt.kaiser | 2008-02-14 01:08:55 +0100 (Thu, 14 Feb 2008) | 2 lines Bring NEWS.txt up to date from check-in msgs. ........ r60772 | raymond.hettinger | 2008-02-14 02:08:02 +0100 (Thu, 14 Feb 2008) | 3 lines Update notes on Decimal. ........ r60773 | raymond.hettinger | 2008-02-14 03:41:22 +0100 (Thu, 14 Feb 2008) | 1 line Fix decimal repr which should have used single quotes like other reprs. ........ r60785 | jeffrey.yasskin | 2008-02-14 07:12:24 +0100 (Thu, 14 Feb 2008) | 11 lines Performance optimizations on Fraction's constructor. ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3)` 31.7 usec/loop -> 9.2 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)'` 27.7 usec/loop -> 9.32 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'Fraction(f)' 31.9 usec/loop -> 14.3 usec/loop ........ r60786 | jeffrey.yasskin | 2008-02-14 08:49:25 +0100 (Thu, 14 Feb 2008) | 5 lines Change simple instances (in Fraction) of self.numerator and self.denominator to self._numerator and self._denominator. This speeds abs() up from 12.2us to 10.8us and trunc() from 2.07us to 1.11us. This doesn't change _add and friends because they're more complicated. ........
2008-02-14 04:27:37 -04:00
>>> from fractions import Fraction
>>> Fraction('3.1415926535897932').limit_denominator(1000)
Fraction(355, 113)
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60766,60769-60786 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60752 | mark.dickinson | 2008-02-12 22:31:59 +0100 (Tue, 12 Feb 2008) | 5 lines Implementation of Fraction.limit_denominator. Remove Fraction.to_continued_fraction and Fraction.from_continued_fraction ........ r60754 | mark.dickinson | 2008-02-12 22:40:53 +0100 (Tue, 12 Feb 2008) | 3 lines Revert change in r60712: turn alternate constructors back into classmethods instead of staticmethods. ........ r60755 | mark.dickinson | 2008-02-12 22:46:54 +0100 (Tue, 12 Feb 2008) | 4 lines Replace R=fractions.Fraction with F=fractions.Fraction in test_fractions.py. This should have been part of the name change from Rational to Fraction. ........ r60758 | georg.brandl | 2008-02-13 08:20:22 +0100 (Wed, 13 Feb 2008) | 3 lines #2063: correct order of utime and stime in os.times() result on Windows. ........ r60762 | jeffrey.yasskin | 2008-02-13 18:58:04 +0100 (Wed, 13 Feb 2008) | 7 lines Working on issue #1762: Brought ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'isinstance(3, Fraction); isinstance(f, Fraction)' from 12.3 usec/loop to 3.44 usec/loop and ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)' from 48.8 usec to 23.6 usec by avoiding genexps and sets in __instancecheck__ and inlining the common case from __subclasscheck__. ........ r60765 | brett.cannon | 2008-02-13 20:15:44 +0100 (Wed, 13 Feb 2008) | 5 lines Fix --enable-universalsdk and its comment line so that zsh's flag completion works. Thanks to Jeroen Ruigrok van der Werven for the fix. ........ r60771 | kurt.kaiser | 2008-02-14 01:08:55 +0100 (Thu, 14 Feb 2008) | 2 lines Bring NEWS.txt up to date from check-in msgs. ........ r60772 | raymond.hettinger | 2008-02-14 02:08:02 +0100 (Thu, 14 Feb 2008) | 3 lines Update notes on Decimal. ........ r60773 | raymond.hettinger | 2008-02-14 03:41:22 +0100 (Thu, 14 Feb 2008) | 1 line Fix decimal repr which should have used single quotes like other reprs. ........ r60785 | jeffrey.yasskin | 2008-02-14 07:12:24 +0100 (Thu, 14 Feb 2008) | 11 lines Performance optimizations on Fraction's constructor. ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3)` 31.7 usec/loop -> 9.2 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)'` 27.7 usec/loop -> 9.32 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'Fraction(f)' 31.9 usec/loop -> 14.3 usec/loop ........ r60786 | jeffrey.yasskin | 2008-02-14 08:49:25 +0100 (Thu, 14 Feb 2008) | 5 lines Change simple instances (in Fraction) of self.numerator and self.denominator to self._numerator and self._denominator. This speeds abs() up from 12.2us to 10.8us and trunc() from 2.07us to 1.11us. This doesn't change _add and friends because they're more complicated. ........
2008-02-14 04:27:37 -04:00
or for recovering a rational number that's represented as a float:
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60766,60769-60786 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60752 | mark.dickinson | 2008-02-12 22:31:59 +0100 (Tue, 12 Feb 2008) | 5 lines Implementation of Fraction.limit_denominator. Remove Fraction.to_continued_fraction and Fraction.from_continued_fraction ........ r60754 | mark.dickinson | 2008-02-12 22:40:53 +0100 (Tue, 12 Feb 2008) | 3 lines Revert change in r60712: turn alternate constructors back into classmethods instead of staticmethods. ........ r60755 | mark.dickinson | 2008-02-12 22:46:54 +0100 (Tue, 12 Feb 2008) | 4 lines Replace R=fractions.Fraction with F=fractions.Fraction in test_fractions.py. This should have been part of the name change from Rational to Fraction. ........ r60758 | georg.brandl | 2008-02-13 08:20:22 +0100 (Wed, 13 Feb 2008) | 3 lines #2063: correct order of utime and stime in os.times() result on Windows. ........ r60762 | jeffrey.yasskin | 2008-02-13 18:58:04 +0100 (Wed, 13 Feb 2008) | 7 lines Working on issue #1762: Brought ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'isinstance(3, Fraction); isinstance(f, Fraction)' from 12.3 usec/loop to 3.44 usec/loop and ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)' from 48.8 usec to 23.6 usec by avoiding genexps and sets in __instancecheck__ and inlining the common case from __subclasscheck__. ........ r60765 | brett.cannon | 2008-02-13 20:15:44 +0100 (Wed, 13 Feb 2008) | 5 lines Fix --enable-universalsdk and its comment line so that zsh's flag completion works. Thanks to Jeroen Ruigrok van der Werven for the fix. ........ r60771 | kurt.kaiser | 2008-02-14 01:08:55 +0100 (Thu, 14 Feb 2008) | 2 lines Bring NEWS.txt up to date from check-in msgs. ........ r60772 | raymond.hettinger | 2008-02-14 02:08:02 +0100 (Thu, 14 Feb 2008) | 3 lines Update notes on Decimal. ........ r60773 | raymond.hettinger | 2008-02-14 03:41:22 +0100 (Thu, 14 Feb 2008) | 1 line Fix decimal repr which should have used single quotes like other reprs. ........ r60785 | jeffrey.yasskin | 2008-02-14 07:12:24 +0100 (Thu, 14 Feb 2008) | 11 lines Performance optimizations on Fraction's constructor. ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3)` 31.7 usec/loop -> 9.2 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)'` 27.7 usec/loop -> 9.32 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'Fraction(f)' 31.9 usec/loop -> 14.3 usec/loop ........ r60786 | jeffrey.yasskin | 2008-02-14 08:49:25 +0100 (Thu, 14 Feb 2008) | 5 lines Change simple instances (in Fraction) of self.numerator and self.denominator to self._numerator and self._denominator. This speeds abs() up from 12.2us to 10.8us and trunc() from 2.07us to 1.11us. This doesn't change _add and friends because they're more complicated. ........
2008-02-14 04:27:37 -04:00
>>> from math import pi, cos
>>> Fraction(cos(pi/3))
Fraction(4503599627370497, 9007199254740992)
>>> Fraction(cos(pi/3)).limit_denominator()
Fraction(1, 2)
>>> Fraction(1.1).limit_denominator()
Fraction(11, 10)
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60766,60769-60786 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60752 | mark.dickinson | 2008-02-12 22:31:59 +0100 (Tue, 12 Feb 2008) | 5 lines Implementation of Fraction.limit_denominator. Remove Fraction.to_continued_fraction and Fraction.from_continued_fraction ........ r60754 | mark.dickinson | 2008-02-12 22:40:53 +0100 (Tue, 12 Feb 2008) | 3 lines Revert change in r60712: turn alternate constructors back into classmethods instead of staticmethods. ........ r60755 | mark.dickinson | 2008-02-12 22:46:54 +0100 (Tue, 12 Feb 2008) | 4 lines Replace R=fractions.Fraction with F=fractions.Fraction in test_fractions.py. This should have been part of the name change from Rational to Fraction. ........ r60758 | georg.brandl | 2008-02-13 08:20:22 +0100 (Wed, 13 Feb 2008) | 3 lines #2063: correct order of utime and stime in os.times() result on Windows. ........ r60762 | jeffrey.yasskin | 2008-02-13 18:58:04 +0100 (Wed, 13 Feb 2008) | 7 lines Working on issue #1762: Brought ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'isinstance(3, Fraction); isinstance(f, Fraction)' from 12.3 usec/loop to 3.44 usec/loop and ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)' from 48.8 usec to 23.6 usec by avoiding genexps and sets in __instancecheck__ and inlining the common case from __subclasscheck__. ........ r60765 | brett.cannon | 2008-02-13 20:15:44 +0100 (Wed, 13 Feb 2008) | 5 lines Fix --enable-universalsdk and its comment line so that zsh's flag completion works. Thanks to Jeroen Ruigrok van der Werven for the fix. ........ r60771 | kurt.kaiser | 2008-02-14 01:08:55 +0100 (Thu, 14 Feb 2008) | 2 lines Bring NEWS.txt up to date from check-in msgs. ........ r60772 | raymond.hettinger | 2008-02-14 02:08:02 +0100 (Thu, 14 Feb 2008) | 3 lines Update notes on Decimal. ........ r60773 | raymond.hettinger | 2008-02-14 03:41:22 +0100 (Thu, 14 Feb 2008) | 1 line Fix decimal repr which should have used single quotes like other reprs. ........ r60785 | jeffrey.yasskin | 2008-02-14 07:12:24 +0100 (Thu, 14 Feb 2008) | 11 lines Performance optimizations on Fraction's constructor. ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3)` 31.7 usec/loop -> 9.2 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)'` 27.7 usec/loop -> 9.32 usec/loop ./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'Fraction(f)' 31.9 usec/loop -> 14.3 usec/loop ........ r60786 | jeffrey.yasskin | 2008-02-14 08:49:25 +0100 (Thu, 14 Feb 2008) | 5 lines Change simple instances (in Fraction) of self.numerator and self.denominator to self._numerator and self._denominator. This speeds abs() up from 12.2us to 10.8us and trunc() from 2.07us to 1.11us. This doesn't change _add and friends because they're more complicated. ........
2008-02-14 04:27:37 -04:00
.. method:: __floor__()
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
Returns the greatest :class:`int` ``<= self``. This method can
also be accessed through the :func:`math.floor` function:
>>> from math import floor
>>> floor(Fraction(355, 113))
3
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
.. method:: __ceil__()
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
Returns the least :class:`int` ``>= self``. This method can
also be accessed through the :func:`math.ceil` function.
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
2008-01-15 17:44:53 -04:00
.. method:: __round__()
__round__(ndigits)
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
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The first version returns the nearest :class:`int` to ``self``,
rounding half to even. The second version rounds ``self`` to the
nearest multiple of ``Fraction(1, 10**ndigits)`` (logically, if
``ndigits`` is negative), again rounding half toward even. This
method can also be accessed through the :func:`round` function.
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
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.. function:: gcd(a, b)
Return the greatest common divisor of the integers *a* and *b*. If either
*a* or *b* is nonzero, then the absolute value of ``gcd(a, b)`` is the
largest integer that divides both *a* and *b*. ``gcd(a,b)`` has the same
sign as *b* if *b* is nonzero; otherwise it takes the sign of *a*. ``gcd(0,
0)`` returns ``0``.
.. deprecated:: 3.5
Use :func:`math.gcd` instead.
Merged revisions 59952-59984 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59952 | thomas.heller | 2008-01-14 02:35:28 -0800 (Mon, 14 Jan 2008) | 1 line Issue 1821: configure libffi for amd64 on FreeeBSD. ........ r59953 | andrew.kuchling | 2008-01-14 06:48:43 -0800 (Mon, 14 Jan 2008) | 1 line Update description of float_info ........ r59959 | raymond.hettinger | 2008-01-14 14:58:05 -0800 (Mon, 14 Jan 2008) | 1 line Fix 1698398: Zipfile.printdir() crashed because the format string expected a tuple object of length six instead of a time.struct_time object. ........ r59961 | andrew.kuchling | 2008-01-14 17:29:16 -0800 (Mon, 14 Jan 2008) | 1 line Typo fixes ........ r59962 | andrew.kuchling | 2008-01-14 17:29:44 -0800 (Mon, 14 Jan 2008) | 1 line Markup fix ........ r59963 | andrew.kuchling | 2008-01-14 17:47:32 -0800 (Mon, 14 Jan 2008) | 1 line Add many items ........ r59964 | andrew.kuchling | 2008-01-14 17:55:32 -0800 (Mon, 14 Jan 2008) | 1 line Repair unfinished sentence ........ r59967 | raymond.hettinger | 2008-01-14 19:02:37 -0800 (Mon, 14 Jan 2008) | 5 lines Issue 1820: structseq objects did not work with the % formatting operator or isinstance(t, tuple). Orignal patch (without tests) by Leif Walsh. ........ r59968 | raymond.hettinger | 2008-01-14 19:07:42 -0800 (Mon, 14 Jan 2008) | 1 line Tighten the definition of a named tuple. ........ r59969 | skip.montanaro | 2008-01-14 19:40:20 -0800 (Mon, 14 Jan 2008) | 3 lines Better (?) text describing the lack of guarantees provided by qsize(), empty() and full(). ........ r59970 | raymond.hettinger | 2008-01-14 21:39:59 -0800 (Mon, 14 Jan 2008) | 1 line Temporarily revert 59967 until GC can be added. ........ r59971 | raymond.hettinger | 2008-01-14 21:46:43 -0800 (Mon, 14 Jan 2008) | 1 line Small grammar nit ........ r59972 | georg.brandl | 2008-01-14 22:55:56 -0800 (Mon, 14 Jan 2008) | 2 lines Typo. ........ r59973 | georg.brandl | 2008-01-14 22:58:15 -0800 (Mon, 14 Jan 2008) | 2 lines Remove duplicate entry. ........ r59974 | jeffrey.yasskin | 2008-01-14 23:46:24 -0800 (Mon, 14 Jan 2008) | 12 lines Add rational.Rational as an implementation of numbers.Rational with infinite precision. This has been discussed at http://bugs.python.org/issue1682. It's useful primarily for teaching, but it also demonstrates how to implement a member of the numeric tower, including fallbacks for mixed-mode arithmetic. I expect to write a couple more patches in this area: * Rational.from_decimal() * Rational.trim/approximate() (maybe with different names) * Maybe remove the parentheses from Rational.__str__() * Maybe rename one of the Rational classes * Maybe make Rational('3/2') work. ........ r59978 | andrew.kuchling | 2008-01-15 06:38:05 -0800 (Tue, 15 Jan 2008) | 8 lines Restore description of sys.dont_write_bytecode. The duplication is intentional -- this paragraph is in a section describing additions to the sys module, and there's a later section that mentions the switch. I think most people scan the what's-new and don't read it in detail, so a bit of duplication is OK. ........ r59984 | guido.van.rossum | 2008-01-15 09:59:29 -0800 (Tue, 15 Jan 2008) | 3 lines Issue #1786 (by myself): pdb should use its own stdin/stdout around an exec call and when creating a recursive instance. ........
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.. seealso::
Module :mod:`numbers`
The abstract base classes making up the numeric tower.