cpython/Doc/library/itertools.rst

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2007-08-15 11:28:22 -03:00
:mod:`itertools` --- Functions creating iterators for efficient looping
=======================================================================
.. module:: itertools
:synopsis: Functions creating iterators for efficient looping.
2007-08-15 11:28:22 -03:00
.. moduleauthor:: Raymond Hettinger <python@rcn.com>
.. sectionauthor:: Raymond Hettinger <python@rcn.com>
Merged revisions 61724-61725,61731-61735,61737,61739,61741,61743-61744,61753,61761,61765-61767,61769,61773,61776-61778,61780-61783,61788,61793,61796,61807,61813 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ................ r61724 | martin.v.loewis | 2008-03-22 01:01:12 +0100 (Sat, 22 Mar 2008) | 49 lines Merged revisions 61602-61723 via svnmerge from svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3 ........ r61626 | david.wolever | 2008-03-19 17:19:16 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added fixer for implicit local imports. See #2414. ........ r61628 | david.wolever | 2008-03-19 17:57:43 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added a class for tests which should not run if a particular import is found. ........ r61629 | collin.winter | 2008-03-19 17:58:19 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Two more relative import fixes in pgen2. ........ r61635 | david.wolever | 2008-03-19 20:16:03 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Fixed print fixer so it will do the Right Thing when it encounters __future__.print_function. 2to3 gets upset, though, so the tests have been commented out. ........ r61637 | david.wolever | 2008-03-19 21:37:17 +0100 (Mi, 19 M?\195?\164r 2008) | 3 lines Added a fixer for itertools imports (from itertools import imap, ifilterfalse --> from itertools import filterfalse) ........ r61645 | david.wolever | 2008-03-19 23:22:35 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line SVN is happier when you add the files you create... -_-' ........ r61654 | david.wolever | 2008-03-20 01:09:56 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added an explicit sort order to fixers -- fixes problems like #2427 ........ r61664 | david.wolever | 2008-03-20 04:32:40 +0100 (Do, 20 M?\195?\164r 2008) | 3 lines Fixes #2428 -- comments are no longer eatten by __future__ fixer. ........ r61673 | david.wolever | 2008-03-20 17:22:40 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added 2to3 node pretty-printer ........ r61679 | david.wolever | 2008-03-20 20:50:42 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Made node printing a little bit prettier ........ r61723 | martin.v.loewis | 2008-03-22 00:59:27 +0100 (Sa, 22 M?\195?\164r 2008) | 2 lines Fix whitespace. ........ ................ r61725 | martin.v.loewis | 2008-03-22 01:02:41 +0100 (Sat, 22 Mar 2008) | 2 lines Install lib2to3. ................ r61731 | facundo.batista | 2008-03-22 03:45:37 +0100 (Sat, 22 Mar 2008) | 4 lines Small fix that complicated the test actually when that test failed. ................ r61732 | alexandre.vassalotti | 2008-03-22 05:08:44 +0100 (Sat, 22 Mar 2008) | 2 lines Added warning for the removal of 'hotshot' in Py3k. ................ r61733 | georg.brandl | 2008-03-22 11:07:29 +0100 (Sat, 22 Mar 2008) | 4 lines #1918: document that weak references *to* an object are cleared before the object's __del__ is called, to ensure that the weak reference callback (if any) finds the object healthy. ................ r61734 | georg.brandl | 2008-03-22 11:56:23 +0100 (Sat, 22 Mar 2008) | 2 lines Activate the Sphinx doctest extension and convert howto/functional to use it. ................ r61735 | georg.brandl | 2008-03-22 11:58:38 +0100 (Sat, 22 Mar 2008) | 2 lines Allow giving source names on the cmdline. ................ r61737 | georg.brandl | 2008-03-22 12:00:48 +0100 (Sat, 22 Mar 2008) | 2 lines Fixup this HOWTO's doctest blocks so that they can be run with sphinx' doctest builder. ................ r61739 | georg.brandl | 2008-03-22 12:47:10 +0100 (Sat, 22 Mar 2008) | 2 lines Test decimal.rst doctests as far as possible with sphinx doctest. ................ r61741 | georg.brandl | 2008-03-22 13:04:26 +0100 (Sat, 22 Mar 2008) | 2 lines Make doctests in re docs usable with sphinx' doctest. ................ r61743 | georg.brandl | 2008-03-22 13:59:37 +0100 (Sat, 22 Mar 2008) | 2 lines Make more doctests in pprint docs testable. ................ r61744 | georg.brandl | 2008-03-22 14:07:06 +0100 (Sat, 22 Mar 2008) | 2 lines No need to specify explicit "doctest_block" anymore. ................ r61753 | georg.brandl | 2008-03-22 21:08:43 +0100 (Sat, 22 Mar 2008) | 2 lines Fix-up syntax problems. ................ r61761 | georg.brandl | 2008-03-22 22:06:20 +0100 (Sat, 22 Mar 2008) | 4 lines Make collections' doctests executable. (The <BLANKLINE>s will be stripped from presentation output.) ................ r61765 | georg.brandl | 2008-03-22 22:21:57 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in datetime docs. ................ r61766 | georg.brandl | 2008-03-22 22:26:44 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in operator docs. ................ r61767 | georg.brandl | 2008-03-22 22:38:33 +0100 (Sat, 22 Mar 2008) | 2 lines Enable doctests in functions.rst. Already found two errors :) ................ r61769 | georg.brandl | 2008-03-22 23:04:10 +0100 (Sat, 22 Mar 2008) | 3 lines Enable doctest running for several other documents. We have now over 640 doctests that are run with "make doctest". ................ r61773 | raymond.hettinger | 2008-03-23 01:55:46 +0100 (Sun, 23 Mar 2008) | 1 line Simplify demo code. ................ r61776 | neal.norwitz | 2008-03-23 04:43:33 +0100 (Sun, 23 Mar 2008) | 7 lines Try to make this test a little more robust and not fail with: timeout (10.0025) is more than 2 seconds more than expected (0.001) I'm assuming this problem is caused by DNS lookup. This change does a DNS lookup of the hostname before trying to connect, so the time is not included. ................ r61777 | neal.norwitz | 2008-03-23 05:08:30 +0100 (Sun, 23 Mar 2008) | 1 line Speed up the test by avoiding socket timeouts. ................ r61778 | neal.norwitz | 2008-03-23 05:43:09 +0100 (Sun, 23 Mar 2008) | 1 line Skip the epoll test if epoll() does not work ................ r61780 | neal.norwitz | 2008-03-23 06:47:20 +0100 (Sun, 23 Mar 2008) | 1 line Suppress failure (to avoid a flaky test) if we cannot connect to svn.python.org ................ r61781 | neal.norwitz | 2008-03-23 07:13:25 +0100 (Sun, 23 Mar 2008) | 4 lines Move itertools before future_builtins since the latter depends on the former. From a clean build importing future_builtins would fail since itertools wasn't built yet. ................ r61782 | neal.norwitz | 2008-03-23 07:16:04 +0100 (Sun, 23 Mar 2008) | 1 line Try to prevent the alarm going off early in tearDown ................ r61783 | neal.norwitz | 2008-03-23 07:19:57 +0100 (Sun, 23 Mar 2008) | 4 lines Remove compiler warnings (on Alpha at least) about using chars as array subscripts. Using chars are dangerous b/c they are signed on some platforms and unsigned on others. ................ r61788 | georg.brandl | 2008-03-23 09:05:30 +0100 (Sun, 23 Mar 2008) | 2 lines Make the doctests presentation-friendlier. ................ r61793 | amaury.forgeotdarc | 2008-03-23 10:55:29 +0100 (Sun, 23 Mar 2008) | 4 lines #1477: ur'\U0010FFFF' raised in narrow unicode builds. Corrected the raw-unicode-escape codec to use UTF-16 surrogates in this case, just like the unicode-escape codec. ................ r61796 | raymond.hettinger | 2008-03-23 14:32:32 +0100 (Sun, 23 Mar 2008) | 1 line Issue 1681432: Add triangular distribution the random module. ................ r61807 | raymond.hettinger | 2008-03-23 20:37:53 +0100 (Sun, 23 Mar 2008) | 4 lines Adopt Nick's suggestion for useful default arguments. Clean-up floating point issues by adding true division and float constants. ................ r61813 | gregory.p.smith | 2008-03-23 22:04:43 +0100 (Sun, 23 Mar 2008) | 6 lines Fix gzip to deal with CRC's being signed values in Python 2.x properly and to read 32bit values as unsigned to start with rather than applying signedness fixups allover the place afterwards. This hopefully fixes the test_tarfile failure on the alpha/tru64 buildbot. ................
2008-03-23 18:54:12 -03:00
.. testsetup::
from itertools import *
Merged revisions 61724-61725,61731-61735,61737,61739,61741,61743-61744,61753,61761,61765-61767,61769,61773,61776-61778,61780-61783,61788,61793,61796,61807,61813 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ................ r61724 | martin.v.loewis | 2008-03-22 01:01:12 +0100 (Sat, 22 Mar 2008) | 49 lines Merged revisions 61602-61723 via svnmerge from svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3 ........ r61626 | david.wolever | 2008-03-19 17:19:16 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added fixer for implicit local imports. See #2414. ........ r61628 | david.wolever | 2008-03-19 17:57:43 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added a class for tests which should not run if a particular import is found. ........ r61629 | collin.winter | 2008-03-19 17:58:19 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Two more relative import fixes in pgen2. ........ r61635 | david.wolever | 2008-03-19 20:16:03 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Fixed print fixer so it will do the Right Thing when it encounters __future__.print_function. 2to3 gets upset, though, so the tests have been commented out. ........ r61637 | david.wolever | 2008-03-19 21:37:17 +0100 (Mi, 19 M?\195?\164r 2008) | 3 lines Added a fixer for itertools imports (from itertools import imap, ifilterfalse --> from itertools import filterfalse) ........ r61645 | david.wolever | 2008-03-19 23:22:35 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line SVN is happier when you add the files you create... -_-' ........ r61654 | david.wolever | 2008-03-20 01:09:56 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added an explicit sort order to fixers -- fixes problems like #2427 ........ r61664 | david.wolever | 2008-03-20 04:32:40 +0100 (Do, 20 M?\195?\164r 2008) | 3 lines Fixes #2428 -- comments are no longer eatten by __future__ fixer. ........ r61673 | david.wolever | 2008-03-20 17:22:40 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added 2to3 node pretty-printer ........ r61679 | david.wolever | 2008-03-20 20:50:42 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Made node printing a little bit prettier ........ r61723 | martin.v.loewis | 2008-03-22 00:59:27 +0100 (Sa, 22 M?\195?\164r 2008) | 2 lines Fix whitespace. ........ ................ r61725 | martin.v.loewis | 2008-03-22 01:02:41 +0100 (Sat, 22 Mar 2008) | 2 lines Install lib2to3. ................ r61731 | facundo.batista | 2008-03-22 03:45:37 +0100 (Sat, 22 Mar 2008) | 4 lines Small fix that complicated the test actually when that test failed. ................ r61732 | alexandre.vassalotti | 2008-03-22 05:08:44 +0100 (Sat, 22 Mar 2008) | 2 lines Added warning for the removal of 'hotshot' in Py3k. ................ r61733 | georg.brandl | 2008-03-22 11:07:29 +0100 (Sat, 22 Mar 2008) | 4 lines #1918: document that weak references *to* an object are cleared before the object's __del__ is called, to ensure that the weak reference callback (if any) finds the object healthy. ................ r61734 | georg.brandl | 2008-03-22 11:56:23 +0100 (Sat, 22 Mar 2008) | 2 lines Activate the Sphinx doctest extension and convert howto/functional to use it. ................ r61735 | georg.brandl | 2008-03-22 11:58:38 +0100 (Sat, 22 Mar 2008) | 2 lines Allow giving source names on the cmdline. ................ r61737 | georg.brandl | 2008-03-22 12:00:48 +0100 (Sat, 22 Mar 2008) | 2 lines Fixup this HOWTO's doctest blocks so that they can be run with sphinx' doctest builder. ................ r61739 | georg.brandl | 2008-03-22 12:47:10 +0100 (Sat, 22 Mar 2008) | 2 lines Test decimal.rst doctests as far as possible with sphinx doctest. ................ r61741 | georg.brandl | 2008-03-22 13:04:26 +0100 (Sat, 22 Mar 2008) | 2 lines Make doctests in re docs usable with sphinx' doctest. ................ r61743 | georg.brandl | 2008-03-22 13:59:37 +0100 (Sat, 22 Mar 2008) | 2 lines Make more doctests in pprint docs testable. ................ r61744 | georg.brandl | 2008-03-22 14:07:06 +0100 (Sat, 22 Mar 2008) | 2 lines No need to specify explicit "doctest_block" anymore. ................ r61753 | georg.brandl | 2008-03-22 21:08:43 +0100 (Sat, 22 Mar 2008) | 2 lines Fix-up syntax problems. ................ r61761 | georg.brandl | 2008-03-22 22:06:20 +0100 (Sat, 22 Mar 2008) | 4 lines Make collections' doctests executable. (The <BLANKLINE>s will be stripped from presentation output.) ................ r61765 | georg.brandl | 2008-03-22 22:21:57 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in datetime docs. ................ r61766 | georg.brandl | 2008-03-22 22:26:44 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in operator docs. ................ r61767 | georg.brandl | 2008-03-22 22:38:33 +0100 (Sat, 22 Mar 2008) | 2 lines Enable doctests in functions.rst. Already found two errors :) ................ r61769 | georg.brandl | 2008-03-22 23:04:10 +0100 (Sat, 22 Mar 2008) | 3 lines Enable doctest running for several other documents. We have now over 640 doctests that are run with "make doctest". ................ r61773 | raymond.hettinger | 2008-03-23 01:55:46 +0100 (Sun, 23 Mar 2008) | 1 line Simplify demo code. ................ r61776 | neal.norwitz | 2008-03-23 04:43:33 +0100 (Sun, 23 Mar 2008) | 7 lines Try to make this test a little more robust and not fail with: timeout (10.0025) is more than 2 seconds more than expected (0.001) I'm assuming this problem is caused by DNS lookup. This change does a DNS lookup of the hostname before trying to connect, so the time is not included. ................ r61777 | neal.norwitz | 2008-03-23 05:08:30 +0100 (Sun, 23 Mar 2008) | 1 line Speed up the test by avoiding socket timeouts. ................ r61778 | neal.norwitz | 2008-03-23 05:43:09 +0100 (Sun, 23 Mar 2008) | 1 line Skip the epoll test if epoll() does not work ................ r61780 | neal.norwitz | 2008-03-23 06:47:20 +0100 (Sun, 23 Mar 2008) | 1 line Suppress failure (to avoid a flaky test) if we cannot connect to svn.python.org ................ r61781 | neal.norwitz | 2008-03-23 07:13:25 +0100 (Sun, 23 Mar 2008) | 4 lines Move itertools before future_builtins since the latter depends on the former. From a clean build importing future_builtins would fail since itertools wasn't built yet. ................ r61782 | neal.norwitz | 2008-03-23 07:16:04 +0100 (Sun, 23 Mar 2008) | 1 line Try to prevent the alarm going off early in tearDown ................ r61783 | neal.norwitz | 2008-03-23 07:19:57 +0100 (Sun, 23 Mar 2008) | 4 lines Remove compiler warnings (on Alpha at least) about using chars as array subscripts. Using chars are dangerous b/c they are signed on some platforms and unsigned on others. ................ r61788 | georg.brandl | 2008-03-23 09:05:30 +0100 (Sun, 23 Mar 2008) | 2 lines Make the doctests presentation-friendlier. ................ r61793 | amaury.forgeotdarc | 2008-03-23 10:55:29 +0100 (Sun, 23 Mar 2008) | 4 lines #1477: ur'\U0010FFFF' raised in narrow unicode builds. Corrected the raw-unicode-escape codec to use UTF-16 surrogates in this case, just like the unicode-escape codec. ................ r61796 | raymond.hettinger | 2008-03-23 14:32:32 +0100 (Sun, 23 Mar 2008) | 1 line Issue 1681432: Add triangular distribution the random module. ................ r61807 | raymond.hettinger | 2008-03-23 20:37:53 +0100 (Sun, 23 Mar 2008) | 4 lines Adopt Nick's suggestion for useful default arguments. Clean-up floating point issues by adding true division and float constants. ................ r61813 | gregory.p.smith | 2008-03-23 22:04:43 +0100 (Sun, 23 Mar 2008) | 6 lines Fix gzip to deal with CRC's being signed values in Python 2.x properly and to read 32bit values as unsigned to start with rather than applying signedness fixups allover the place afterwards. This hopefully fixes the test_tarfile failure on the alpha/tru64 buildbot. ................
2008-03-23 18:54:12 -03:00
--------------
Merged revisions 61724-61725,61731-61735,61737,61739,61741,61743-61744,61753,61761,61765-61767,61769,61773,61776-61778,61780-61783,61788,61793,61796,61807,61813 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ................ r61724 | martin.v.loewis | 2008-03-22 01:01:12 +0100 (Sat, 22 Mar 2008) | 49 lines Merged revisions 61602-61723 via svnmerge from svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3 ........ r61626 | david.wolever | 2008-03-19 17:19:16 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added fixer for implicit local imports. See #2414. ........ r61628 | david.wolever | 2008-03-19 17:57:43 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added a class for tests which should not run if a particular import is found. ........ r61629 | collin.winter | 2008-03-19 17:58:19 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Two more relative import fixes in pgen2. ........ r61635 | david.wolever | 2008-03-19 20:16:03 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Fixed print fixer so it will do the Right Thing when it encounters __future__.print_function. 2to3 gets upset, though, so the tests have been commented out. ........ r61637 | david.wolever | 2008-03-19 21:37:17 +0100 (Mi, 19 M?\195?\164r 2008) | 3 lines Added a fixer for itertools imports (from itertools import imap, ifilterfalse --> from itertools import filterfalse) ........ r61645 | david.wolever | 2008-03-19 23:22:35 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line SVN is happier when you add the files you create... -_-' ........ r61654 | david.wolever | 2008-03-20 01:09:56 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added an explicit sort order to fixers -- fixes problems like #2427 ........ r61664 | david.wolever | 2008-03-20 04:32:40 +0100 (Do, 20 M?\195?\164r 2008) | 3 lines Fixes #2428 -- comments are no longer eatten by __future__ fixer. ........ r61673 | david.wolever | 2008-03-20 17:22:40 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added 2to3 node pretty-printer ........ r61679 | david.wolever | 2008-03-20 20:50:42 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Made node printing a little bit prettier ........ r61723 | martin.v.loewis | 2008-03-22 00:59:27 +0100 (Sa, 22 M?\195?\164r 2008) | 2 lines Fix whitespace. ........ ................ r61725 | martin.v.loewis | 2008-03-22 01:02:41 +0100 (Sat, 22 Mar 2008) | 2 lines Install lib2to3. ................ r61731 | facundo.batista | 2008-03-22 03:45:37 +0100 (Sat, 22 Mar 2008) | 4 lines Small fix that complicated the test actually when that test failed. ................ r61732 | alexandre.vassalotti | 2008-03-22 05:08:44 +0100 (Sat, 22 Mar 2008) | 2 lines Added warning for the removal of 'hotshot' in Py3k. ................ r61733 | georg.brandl | 2008-03-22 11:07:29 +0100 (Sat, 22 Mar 2008) | 4 lines #1918: document that weak references *to* an object are cleared before the object's __del__ is called, to ensure that the weak reference callback (if any) finds the object healthy. ................ r61734 | georg.brandl | 2008-03-22 11:56:23 +0100 (Sat, 22 Mar 2008) | 2 lines Activate the Sphinx doctest extension and convert howto/functional to use it. ................ r61735 | georg.brandl | 2008-03-22 11:58:38 +0100 (Sat, 22 Mar 2008) | 2 lines Allow giving source names on the cmdline. ................ r61737 | georg.brandl | 2008-03-22 12:00:48 +0100 (Sat, 22 Mar 2008) | 2 lines Fixup this HOWTO's doctest blocks so that they can be run with sphinx' doctest builder. ................ r61739 | georg.brandl | 2008-03-22 12:47:10 +0100 (Sat, 22 Mar 2008) | 2 lines Test decimal.rst doctests as far as possible with sphinx doctest. ................ r61741 | georg.brandl | 2008-03-22 13:04:26 +0100 (Sat, 22 Mar 2008) | 2 lines Make doctests in re docs usable with sphinx' doctest. ................ r61743 | georg.brandl | 2008-03-22 13:59:37 +0100 (Sat, 22 Mar 2008) | 2 lines Make more doctests in pprint docs testable. ................ r61744 | georg.brandl | 2008-03-22 14:07:06 +0100 (Sat, 22 Mar 2008) | 2 lines No need to specify explicit "doctest_block" anymore. ................ r61753 | georg.brandl | 2008-03-22 21:08:43 +0100 (Sat, 22 Mar 2008) | 2 lines Fix-up syntax problems. ................ r61761 | georg.brandl | 2008-03-22 22:06:20 +0100 (Sat, 22 Mar 2008) | 4 lines Make collections' doctests executable. (The <BLANKLINE>s will be stripped from presentation output.) ................ r61765 | georg.brandl | 2008-03-22 22:21:57 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in datetime docs. ................ r61766 | georg.brandl | 2008-03-22 22:26:44 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in operator docs. ................ r61767 | georg.brandl | 2008-03-22 22:38:33 +0100 (Sat, 22 Mar 2008) | 2 lines Enable doctests in functions.rst. Already found two errors :) ................ r61769 | georg.brandl | 2008-03-22 23:04:10 +0100 (Sat, 22 Mar 2008) | 3 lines Enable doctest running for several other documents. We have now over 640 doctests that are run with "make doctest". ................ r61773 | raymond.hettinger | 2008-03-23 01:55:46 +0100 (Sun, 23 Mar 2008) | 1 line Simplify demo code. ................ r61776 | neal.norwitz | 2008-03-23 04:43:33 +0100 (Sun, 23 Mar 2008) | 7 lines Try to make this test a little more robust and not fail with: timeout (10.0025) is more than 2 seconds more than expected (0.001) I'm assuming this problem is caused by DNS lookup. This change does a DNS lookup of the hostname before trying to connect, so the time is not included. ................ r61777 | neal.norwitz | 2008-03-23 05:08:30 +0100 (Sun, 23 Mar 2008) | 1 line Speed up the test by avoiding socket timeouts. ................ r61778 | neal.norwitz | 2008-03-23 05:43:09 +0100 (Sun, 23 Mar 2008) | 1 line Skip the epoll test if epoll() does not work ................ r61780 | neal.norwitz | 2008-03-23 06:47:20 +0100 (Sun, 23 Mar 2008) | 1 line Suppress failure (to avoid a flaky test) if we cannot connect to svn.python.org ................ r61781 | neal.norwitz | 2008-03-23 07:13:25 +0100 (Sun, 23 Mar 2008) | 4 lines Move itertools before future_builtins since the latter depends on the former. From a clean build importing future_builtins would fail since itertools wasn't built yet. ................ r61782 | neal.norwitz | 2008-03-23 07:16:04 +0100 (Sun, 23 Mar 2008) | 1 line Try to prevent the alarm going off early in tearDown ................ r61783 | neal.norwitz | 2008-03-23 07:19:57 +0100 (Sun, 23 Mar 2008) | 4 lines Remove compiler warnings (on Alpha at least) about using chars as array subscripts. Using chars are dangerous b/c they are signed on some platforms and unsigned on others. ................ r61788 | georg.brandl | 2008-03-23 09:05:30 +0100 (Sun, 23 Mar 2008) | 2 lines Make the doctests presentation-friendlier. ................ r61793 | amaury.forgeotdarc | 2008-03-23 10:55:29 +0100 (Sun, 23 Mar 2008) | 4 lines #1477: ur'\U0010FFFF' raised in narrow unicode builds. Corrected the raw-unicode-escape codec to use UTF-16 surrogates in this case, just like the unicode-escape codec. ................ r61796 | raymond.hettinger | 2008-03-23 14:32:32 +0100 (Sun, 23 Mar 2008) | 1 line Issue 1681432: Add triangular distribution the random module. ................ r61807 | raymond.hettinger | 2008-03-23 20:37:53 +0100 (Sun, 23 Mar 2008) | 4 lines Adopt Nick's suggestion for useful default arguments. Clean-up floating point issues by adding true division and float constants. ................ r61813 | gregory.p.smith | 2008-03-23 22:04:43 +0100 (Sun, 23 Mar 2008) | 6 lines Fix gzip to deal with CRC's being signed values in Python 2.x properly and to read 32bit values as unsigned to start with rather than applying signedness fixups allover the place afterwards. This hopefully fixes the test_tarfile failure on the alpha/tru64 buildbot. ................
2008-03-23 18:54:12 -03:00
This module implements a number of :term:`iterator` building blocks inspired
by constructs from APL, Haskell, and SML. Each has been recast in a form
suitable for Python.
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The module standardizes a core set of fast, memory efficient tools that are
useful by themselves or in combination. Together, they form an "iterator
algebra" making it possible to construct specialized tools succinctly and
efficiently in pure Python.
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For instance, SML provides a tabulation tool: ``tabulate(f)`` which produces a
sequence ``f(0), f(1), ...``. The same effect can be achieved in Python
by combining :func:`map` and :func:`count` to form ``map(f, count())``.
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These tools and their built-in counterparts also work well with the high-speed
functions in the :mod:`operator` module. For example, the multiplication
operator can be mapped across two vectors to form an efficient dot-product:
``sum(map(operator.mul, vector1, vector2))``.
**Infinite Iterators:**
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================== ================= ================================================= =========================================
Iterator Arguments Results Example
================== ================= ================================================= =========================================
:func:`count` start, [step] start, start+step, start+2*step, ... ``count(10) --> 10 11 12 13 14 ...``
:func:`cycle` p p0, p1, ... plast, p0, p1, ... ``cycle('ABCD') --> A B C D A B C D ...``
:func:`repeat` elem [,n] elem, elem, elem, ... endlessly or up to n times ``repeat(10, 3) --> 10 10 10``
================== ================= ================================================= =========================================
**Iterators terminating on the shortest input sequence:**
============================ ============================ ================================================= =============================================================
Iterator Arguments Results Example
============================ ============================ ================================================= =============================================================
:func:`accumulate` p [,func] p0, p0+p1, p0+p1+p2, ... ``accumulate([1,2,3,4,5]) --> 1 3 6 10 15``
:func:`chain` p, q, ... p0, p1, ... plast, q0, q1, ... ``chain('ABC', 'DEF') --> A B C D E F``
:func:`chain.from_iterable` iterable p0, p1, ... plast, q0, q1, ... ``chain.from_iterable(['ABC', 'DEF']) --> A B C D E F``
:func:`compress` data, selectors (d[0] if s[0]), (d[1] if s[1]), ... ``compress('ABCDEF', [1,0,1,0,1,1]) --> A C E F``
:func:`dropwhile` pred, seq seq[n], seq[n+1], starting when pred fails ``dropwhile(lambda x: x<5, [1,4,6,4,1]) --> 6 4 1``
:func:`filterfalse` pred, seq elements of seq where pred(elem) is false ``filterfalse(lambda x: x%2, range(10)) --> 0 2 4 6 8``
:func:`groupby` iterable[, keyfunc] sub-iterators grouped by value of keyfunc(v)
:func:`islice` seq, [start,] stop [, step] elements from seq[start:stop:step] ``islice('ABCDEFG', 2, None) --> C D E F G``
:func:`starmap` func, seq func(\*seq[0]), func(\*seq[1]), ... ``starmap(pow, [(2,5), (3,2), (10,3)]) --> 32 9 1000``
:func:`takewhile` pred, seq seq[0], seq[1], until pred fails ``takewhile(lambda x: x<5, [1,4,6,4,1]) --> 1 4``
:func:`tee` it, n it1, it2, ... itn splits one iterator into n
:func:`zip_longest` p, q, ... (p[0], q[0]), (p[1], q[1]), ... ``zip_longest('ABCD', 'xy', fillvalue='-') --> Ax By C- D-``
============================ ============================ ================================================= =============================================================
**Combinatoric generators:**
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============================================== ==================== =============================================================
Iterator Arguments Results
============================================== ==================== =============================================================
:func:`product` p, q, ... [repeat=1] cartesian product, equivalent to a nested for-loop
:func:`permutations` p[, r] r-length tuples, all possible orderings, no repeated elements
:func:`combinations` p, r r-length tuples, in sorted order, no repeated elements
:func:`combinations_with_replacement` p, r r-length tuples, in sorted order, with repeated elements
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``product('ABCD', repeat=2)`` ``AA AB AC AD BA BB BC BD CA CB CC CD DA DB DC DD``
``permutations('ABCD', 2)`` ``AB AC AD BA BC BD CA CB CD DA DB DC``
``combinations('ABCD', 2)`` ``AB AC AD BC BD CD``
``combinations_with_replacement('ABCD', 2)`` ``AA AB AC AD BB BC BD CC CD DD``
============================================== ==================== =============================================================
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.. _itertools-functions:
Itertool functions
------------------
The following module functions all construct and return iterators. Some provide
streams of infinite length, so they should only be accessed by functions or
loops that truncate the stream.
.. function:: accumulate(iterable[, func])
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Make an iterator that returns accumulated sums, or accumulated
results of other binary functions (specified via the optional
*func* argument). If *func* is supplied, it should be a function
of two arguments. Elements of the input *iterable* may be any type
that can be accepted as arguments to *func*. (For example, with
the default operation of addition, elements may be any addable
type including :class:`~decimal.Decimal` or
:class:`~fractions.Fraction`.) If the input iterable is empty, the
output iterable will also be empty.
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Roughly equivalent to::
def accumulate(iterable, func=operator.add):
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'Return running totals'
# accumulate([1,2,3,4,5]) --> 1 3 6 10 15
# accumulate([1,2,3,4,5], operator.mul) --> 1 2 6 24 120
it = iter(iterable)
try:
total = next(it)
except StopIteration:
return
yield total
for element in it:
total = func(total, element)
yield total
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There are a number of uses for the *func* argument. It can be set to
:func:`min` for a running minimum, :func:`max` for a running maximum, or
:func:`operator.mul` for a running product. Amortization tables can be
built by accumulating interest and applying payments. First-order
`recurrence relations <https://en.wikipedia.org/wiki/Recurrence_relation>`_
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can be modeled by supplying the initial value in the iterable and using only
the accumulated total in *func* argument::
>>> data = [3, 4, 6, 2, 1, 9, 0, 7, 5, 8]
>>> list(accumulate(data, operator.mul)) # running product
[3, 12, 72, 144, 144, 1296, 0, 0, 0, 0]
>>> list(accumulate(data, max)) # running maximum
[3, 4, 6, 6, 6, 9, 9, 9, 9, 9]
# Amortize a 5% loan of 1000 with 4 annual payments of 90
>>> cashflows = [1000, -90, -90, -90, -90]
>>> list(accumulate(cashflows, lambda bal, pmt: bal*1.05 + pmt))
[1000, 960.0, 918.0, 873.9000000000001, 827.5950000000001]
# Chaotic recurrence relation https://en.wikipedia.org/wiki/Logistic_map
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>>> logistic_map = lambda x, _: r * x * (1 - x)
>>> r = 3.8
>>> x0 = 0.4
>>> inputs = repeat(x0, 36) # only the initial value is used
>>> [format(x, '.2f') for x in accumulate(inputs, logistic_map)]
['0.40', '0.91', '0.30', '0.81', '0.60', '0.92', '0.29', '0.79', '0.63',
'0.88', '0.39', '0.90', '0.33', '0.84', '0.52', '0.95', '0.18', '0.57',
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'0.93', '0.25', '0.71', '0.79', '0.63', '0.88', '0.39', '0.91', '0.32',
'0.83', '0.54', '0.95', '0.20', '0.60', '0.91', '0.30', '0.80', '0.60']
See :func:`functools.reduce` for a similar function that returns only the
final accumulated value.
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.. versionadded:: 3.2
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.. versionchanged:: 3.3
Added the optional *func* parameter.
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.. function:: chain(*iterables)
Make an iterator that returns elements from the first iterable until it is
exhausted, then proceeds to the next iterable, until all of the iterables are
exhausted. Used for treating consecutive sequences as a single sequence.
Roughly equivalent to::
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def chain(*iterables):
# chain('ABC', 'DEF') --> A B C D E F
for it in iterables:
for element in it:
yield element
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.. classmethod:: chain.from_iterable(iterable)
Alternate constructor for :func:`chain`. Gets chained inputs from a
single iterable argument that is evaluated lazily. Roughly equivalent to::
def from_iterable(iterables):
# chain.from_iterable(['ABC', 'DEF']) --> A B C D E F
for it in iterables:
for element in it:
yield element
Merged revisions 61209-61214,61217-61222,61224-61226,61233-61237 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61209 | georg.brandl | 2008-03-03 21:37:55 +0100 (Mon, 03 Mar 2008) | 2 lines There are now sixteen isfoo functions. ........ r61210 | georg.brandl | 2008-03-03 21:39:00 +0100 (Mon, 03 Mar 2008) | 2 lines 15 -> 16, the 2nd ........ r61211 | georg.brandl | 2008-03-03 22:22:47 +0100 (Mon, 03 Mar 2008) | 2 lines Actually import itertools. ........ r61212 | georg.brandl | 2008-03-03 22:31:50 +0100 (Mon, 03 Mar 2008) | 2 lines Expand a bit on genexp scopes. ........ r61213 | raymond.hettinger | 2008-03-03 23:04:55 +0100 (Mon, 03 Mar 2008) | 1 line Remove dependency on itertools -- a simple genexp suffices. ........ r61214 | raymond.hettinger | 2008-03-03 23:19:58 +0100 (Mon, 03 Mar 2008) | 1 line Issue 2226: Callable checked for the wrong abstract method. ........ r61217 | andrew.kuchling | 2008-03-04 01:40:32 +0100 (Tue, 04 Mar 2008) | 1 line Typo fix ........ r61218 | andrew.kuchling | 2008-03-04 02:30:10 +0100 (Tue, 04 Mar 2008) | 1 line Grammar fix; markup fix ........ r61219 | andrew.kuchling | 2008-03-04 02:47:38 +0100 (Tue, 04 Mar 2008) | 1 line Fix sentence fragment ........ r61220 | andrew.kuchling | 2008-03-04 02:48:26 +0100 (Tue, 04 Mar 2008) | 1 line Typo fix ........ r61221 | andrew.kuchling | 2008-03-04 02:49:37 +0100 (Tue, 04 Mar 2008) | 1 line Add versionadded tags ........ r61222 | andrew.kuchling | 2008-03-04 02:50:32 +0100 (Tue, 04 Mar 2008) | 1 line Thesis night results: add various items ........ r61224 | raymond.hettinger | 2008-03-04 05:17:08 +0100 (Tue, 04 Mar 2008) | 1 line Beef-up docs and tests for itertools. Fix-up end-case for product(). ........ r61225 | georg.brandl | 2008-03-04 08:25:54 +0100 (Tue, 04 Mar 2008) | 2 lines Fix some patch attributions. ........ r61226 | georg.brandl | 2008-03-04 08:33:30 +0100 (Tue, 04 Mar 2008) | 2 lines #2230: document that PyArg_* leaves addresses alone on error. ........ r61233 | neal.norwitz | 2008-03-04 17:22:46 +0100 (Tue, 04 Mar 2008) | 3 lines Close the file before trying to remove the directory so it works on Windows. As reported by Trent Nelson on python-dev. ........ r61234 | thomas.heller | 2008-03-04 21:09:11 +0100 (Tue, 04 Mar 2008) | 9 lines Merged changes from libffi3-branch. The bundled libffi copy is now in sync with the recently released libffi3.0.4 version, apart from some small changes to Modules/_ctypes/libffi/configure.ac. I gave up on using libffi3 files on os x. Instead, static configuration with files from pyobjc is used. ........ r61235 | thomas.heller | 2008-03-04 21:21:42 +0100 (Tue, 04 Mar 2008) | 1 line Try to fix the build for PY_LINUX. ........ r61236 | fred.drake | 2008-03-04 22:14:04 +0100 (Tue, 04 Mar 2008) | 2 lines fix typo ........ r61237 | raymond.hettinger | 2008-03-04 23:29:44 +0100 (Tue, 04 Mar 2008) | 1 line Fix refleak in chain(). ........
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Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61064,61066-61080 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61063 | andrew.kuchling | 2008-02-25 17:29:19 +0100 (Mon, 25 Feb 2008) | 1 line Move .setupterm() output so that we don't try to call endwin() if it fails ........ r61064 | andrew.kuchling | 2008-02-25 17:29:58 +0100 (Mon, 25 Feb 2008) | 1 line Use file descriptor for real stdout ........ r61067 | facundo.batista | 2008-02-25 19:06:00 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2117. Update compiler module to handle class decorators. Thanks Thomas Herve ........ r61069 | georg.brandl | 2008-02-25 21:17:56 +0100 (Mon, 25 Feb 2008) | 2 lines Rename sphinx.addons to sphinx.ext. ........ r61071 | georg.brandl | 2008-02-25 21:20:45 +0100 (Mon, 25 Feb 2008) | 2 lines Revert r61029. ........ r61072 | facundo.batista | 2008-02-25 23:33:55 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2168. gdbm and dbm needs to be iterable; this fixes a failure in the shelve module. Thanks Thomas Herve. ........ r61073 | raymond.hettinger | 2008-02-25 23:42:32 +0100 (Mon, 25 Feb 2008) | 1 line Make sure the itertools filter functions give the same performance for func=bool as func=None. ........ r61074 | raymond.hettinger | 2008-02-26 00:17:41 +0100 (Tue, 26 Feb 2008) | 1 line Revert part of r60927 which made invalid assumptions about the API offered by db modules. ........ r61075 | facundo.batista | 2008-02-26 00:46:02 +0100 (Tue, 26 Feb 2008) | 3 lines Coerced PyBool_Type to be able to compare it. ........ r61076 | raymond.hettinger | 2008-02-26 03:46:54 +0100 (Tue, 26 Feb 2008) | 1 line Docs for itertools.combinations(). Implementation in forthcoming checkin. ........ r61077 | neal.norwitz | 2008-02-26 05:50:37 +0100 (Tue, 26 Feb 2008) | 3 lines Don't use a hard coded port. This test could hang/fail if the port is in use. Speed this test up by avoiding a sleep and using the event. ........ r61078 | neal.norwitz | 2008-02-26 06:12:50 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61079 | neal.norwitz | 2008-02-26 06:23:51 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61080 | georg.brandl | 2008-02-26 07:40:10 +0100 (Tue, 26 Feb 2008) | 2 lines Banish tab. ........
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.. function:: combinations(iterable, r)
Return *r* length subsequences of elements from the input *iterable*.
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61064,61066-61080 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61063 | andrew.kuchling | 2008-02-25 17:29:19 +0100 (Mon, 25 Feb 2008) | 1 line Move .setupterm() output so that we don't try to call endwin() if it fails ........ r61064 | andrew.kuchling | 2008-02-25 17:29:58 +0100 (Mon, 25 Feb 2008) | 1 line Use file descriptor for real stdout ........ r61067 | facundo.batista | 2008-02-25 19:06:00 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2117. Update compiler module to handle class decorators. Thanks Thomas Herve ........ r61069 | georg.brandl | 2008-02-25 21:17:56 +0100 (Mon, 25 Feb 2008) | 2 lines Rename sphinx.addons to sphinx.ext. ........ r61071 | georg.brandl | 2008-02-25 21:20:45 +0100 (Mon, 25 Feb 2008) | 2 lines Revert r61029. ........ r61072 | facundo.batista | 2008-02-25 23:33:55 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2168. gdbm and dbm needs to be iterable; this fixes a failure in the shelve module. Thanks Thomas Herve. ........ r61073 | raymond.hettinger | 2008-02-25 23:42:32 +0100 (Mon, 25 Feb 2008) | 1 line Make sure the itertools filter functions give the same performance for func=bool as func=None. ........ r61074 | raymond.hettinger | 2008-02-26 00:17:41 +0100 (Tue, 26 Feb 2008) | 1 line Revert part of r60927 which made invalid assumptions about the API offered by db modules. ........ r61075 | facundo.batista | 2008-02-26 00:46:02 +0100 (Tue, 26 Feb 2008) | 3 lines Coerced PyBool_Type to be able to compare it. ........ r61076 | raymond.hettinger | 2008-02-26 03:46:54 +0100 (Tue, 26 Feb 2008) | 1 line Docs for itertools.combinations(). Implementation in forthcoming checkin. ........ r61077 | neal.norwitz | 2008-02-26 05:50:37 +0100 (Tue, 26 Feb 2008) | 3 lines Don't use a hard coded port. This test could hang/fail if the port is in use. Speed this test up by avoiding a sleep and using the event. ........ r61078 | neal.norwitz | 2008-02-26 06:12:50 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61079 | neal.norwitz | 2008-02-26 06:23:51 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61080 | georg.brandl | 2008-02-26 07:40:10 +0100 (Tue, 26 Feb 2008) | 2 lines Banish tab. ........
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Combinations are emitted in lexicographic sort order. So, if the
input *iterable* is sorted, the combination tuples will be produced
in sorted order.
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61064,61066-61080 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61063 | andrew.kuchling | 2008-02-25 17:29:19 +0100 (Mon, 25 Feb 2008) | 1 line Move .setupterm() output so that we don't try to call endwin() if it fails ........ r61064 | andrew.kuchling | 2008-02-25 17:29:58 +0100 (Mon, 25 Feb 2008) | 1 line Use file descriptor for real stdout ........ r61067 | facundo.batista | 2008-02-25 19:06:00 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2117. Update compiler module to handle class decorators. Thanks Thomas Herve ........ r61069 | georg.brandl | 2008-02-25 21:17:56 +0100 (Mon, 25 Feb 2008) | 2 lines Rename sphinx.addons to sphinx.ext. ........ r61071 | georg.brandl | 2008-02-25 21:20:45 +0100 (Mon, 25 Feb 2008) | 2 lines Revert r61029. ........ r61072 | facundo.batista | 2008-02-25 23:33:55 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2168. gdbm and dbm needs to be iterable; this fixes a failure in the shelve module. Thanks Thomas Herve. ........ r61073 | raymond.hettinger | 2008-02-25 23:42:32 +0100 (Mon, 25 Feb 2008) | 1 line Make sure the itertools filter functions give the same performance for func=bool as func=None. ........ r61074 | raymond.hettinger | 2008-02-26 00:17:41 +0100 (Tue, 26 Feb 2008) | 1 line Revert part of r60927 which made invalid assumptions about the API offered by db modules. ........ r61075 | facundo.batista | 2008-02-26 00:46:02 +0100 (Tue, 26 Feb 2008) | 3 lines Coerced PyBool_Type to be able to compare it. ........ r61076 | raymond.hettinger | 2008-02-26 03:46:54 +0100 (Tue, 26 Feb 2008) | 1 line Docs for itertools.combinations(). Implementation in forthcoming checkin. ........ r61077 | neal.norwitz | 2008-02-26 05:50:37 +0100 (Tue, 26 Feb 2008) | 3 lines Don't use a hard coded port. This test could hang/fail if the port is in use. Speed this test up by avoiding a sleep and using the event. ........ r61078 | neal.norwitz | 2008-02-26 06:12:50 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61079 | neal.norwitz | 2008-02-26 06:23:51 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61080 | georg.brandl | 2008-02-26 07:40:10 +0100 (Tue, 26 Feb 2008) | 2 lines Banish tab. ........
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Elements are treated as unique based on their position, not on their
value. So if the input elements are unique, there will be no repeat
values in each combination.
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61064,61066-61080 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61063 | andrew.kuchling | 2008-02-25 17:29:19 +0100 (Mon, 25 Feb 2008) | 1 line Move .setupterm() output so that we don't try to call endwin() if it fails ........ r61064 | andrew.kuchling | 2008-02-25 17:29:58 +0100 (Mon, 25 Feb 2008) | 1 line Use file descriptor for real stdout ........ r61067 | facundo.batista | 2008-02-25 19:06:00 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2117. Update compiler module to handle class decorators. Thanks Thomas Herve ........ r61069 | georg.brandl | 2008-02-25 21:17:56 +0100 (Mon, 25 Feb 2008) | 2 lines Rename sphinx.addons to sphinx.ext. ........ r61071 | georg.brandl | 2008-02-25 21:20:45 +0100 (Mon, 25 Feb 2008) | 2 lines Revert r61029. ........ r61072 | facundo.batista | 2008-02-25 23:33:55 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2168. gdbm and dbm needs to be iterable; this fixes a failure in the shelve module. Thanks Thomas Herve. ........ r61073 | raymond.hettinger | 2008-02-25 23:42:32 +0100 (Mon, 25 Feb 2008) | 1 line Make sure the itertools filter functions give the same performance for func=bool as func=None. ........ r61074 | raymond.hettinger | 2008-02-26 00:17:41 +0100 (Tue, 26 Feb 2008) | 1 line Revert part of r60927 which made invalid assumptions about the API offered by db modules. ........ r61075 | facundo.batista | 2008-02-26 00:46:02 +0100 (Tue, 26 Feb 2008) | 3 lines Coerced PyBool_Type to be able to compare it. ........ r61076 | raymond.hettinger | 2008-02-26 03:46:54 +0100 (Tue, 26 Feb 2008) | 1 line Docs for itertools.combinations(). Implementation in forthcoming checkin. ........ r61077 | neal.norwitz | 2008-02-26 05:50:37 +0100 (Tue, 26 Feb 2008) | 3 lines Don't use a hard coded port. This test could hang/fail if the port is in use. Speed this test up by avoiding a sleep and using the event. ........ r61078 | neal.norwitz | 2008-02-26 06:12:50 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61079 | neal.norwitz | 2008-02-26 06:23:51 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61080 | georg.brandl | 2008-02-26 07:40:10 +0100 (Tue, 26 Feb 2008) | 2 lines Banish tab. ........
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Roughly equivalent to::
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61064,61066-61080 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61063 | andrew.kuchling | 2008-02-25 17:29:19 +0100 (Mon, 25 Feb 2008) | 1 line Move .setupterm() output so that we don't try to call endwin() if it fails ........ r61064 | andrew.kuchling | 2008-02-25 17:29:58 +0100 (Mon, 25 Feb 2008) | 1 line Use file descriptor for real stdout ........ r61067 | facundo.batista | 2008-02-25 19:06:00 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2117. Update compiler module to handle class decorators. Thanks Thomas Herve ........ r61069 | georg.brandl | 2008-02-25 21:17:56 +0100 (Mon, 25 Feb 2008) | 2 lines Rename sphinx.addons to sphinx.ext. ........ r61071 | georg.brandl | 2008-02-25 21:20:45 +0100 (Mon, 25 Feb 2008) | 2 lines Revert r61029. ........ r61072 | facundo.batista | 2008-02-25 23:33:55 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2168. gdbm and dbm needs to be iterable; this fixes a failure in the shelve module. Thanks Thomas Herve. ........ r61073 | raymond.hettinger | 2008-02-25 23:42:32 +0100 (Mon, 25 Feb 2008) | 1 line Make sure the itertools filter functions give the same performance for func=bool as func=None. ........ r61074 | raymond.hettinger | 2008-02-26 00:17:41 +0100 (Tue, 26 Feb 2008) | 1 line Revert part of r60927 which made invalid assumptions about the API offered by db modules. ........ r61075 | facundo.batista | 2008-02-26 00:46:02 +0100 (Tue, 26 Feb 2008) | 3 lines Coerced PyBool_Type to be able to compare it. ........ r61076 | raymond.hettinger | 2008-02-26 03:46:54 +0100 (Tue, 26 Feb 2008) | 1 line Docs for itertools.combinations(). Implementation in forthcoming checkin. ........ r61077 | neal.norwitz | 2008-02-26 05:50:37 +0100 (Tue, 26 Feb 2008) | 3 lines Don't use a hard coded port. This test could hang/fail if the port is in use. Speed this test up by avoiding a sleep and using the event. ........ r61078 | neal.norwitz | 2008-02-26 06:12:50 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61079 | neal.norwitz | 2008-02-26 06:23:51 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61080 | georg.brandl | 2008-02-26 07:40:10 +0100 (Tue, 26 Feb 2008) | 2 lines Banish tab. ........
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def combinations(iterable, r):
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# combinations('ABCD', 2) --> AB AC AD BC BD CD
# combinations(range(4), 3) --> 012 013 023 123
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61064,61066-61080 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61063 | andrew.kuchling | 2008-02-25 17:29:19 +0100 (Mon, 25 Feb 2008) | 1 line Move .setupterm() output so that we don't try to call endwin() if it fails ........ r61064 | andrew.kuchling | 2008-02-25 17:29:58 +0100 (Mon, 25 Feb 2008) | 1 line Use file descriptor for real stdout ........ r61067 | facundo.batista | 2008-02-25 19:06:00 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2117. Update compiler module to handle class decorators. Thanks Thomas Herve ........ r61069 | georg.brandl | 2008-02-25 21:17:56 +0100 (Mon, 25 Feb 2008) | 2 lines Rename sphinx.addons to sphinx.ext. ........ r61071 | georg.brandl | 2008-02-25 21:20:45 +0100 (Mon, 25 Feb 2008) | 2 lines Revert r61029. ........ r61072 | facundo.batista | 2008-02-25 23:33:55 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2168. gdbm and dbm needs to be iterable; this fixes a failure in the shelve module. Thanks Thomas Herve. ........ r61073 | raymond.hettinger | 2008-02-25 23:42:32 +0100 (Mon, 25 Feb 2008) | 1 line Make sure the itertools filter functions give the same performance for func=bool as func=None. ........ r61074 | raymond.hettinger | 2008-02-26 00:17:41 +0100 (Tue, 26 Feb 2008) | 1 line Revert part of r60927 which made invalid assumptions about the API offered by db modules. ........ r61075 | facundo.batista | 2008-02-26 00:46:02 +0100 (Tue, 26 Feb 2008) | 3 lines Coerced PyBool_Type to be able to compare it. ........ r61076 | raymond.hettinger | 2008-02-26 03:46:54 +0100 (Tue, 26 Feb 2008) | 1 line Docs for itertools.combinations(). Implementation in forthcoming checkin. ........ r61077 | neal.norwitz | 2008-02-26 05:50:37 +0100 (Tue, 26 Feb 2008) | 3 lines Don't use a hard coded port. This test could hang/fail if the port is in use. Speed this test up by avoiding a sleep and using the event. ........ r61078 | neal.norwitz | 2008-02-26 06:12:50 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61079 | neal.norwitz | 2008-02-26 06:23:51 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61080 | georg.brandl | 2008-02-26 07:40:10 +0100 (Tue, 26 Feb 2008) | 2 lines Banish tab. ........
2008-02-26 04:18:30 -04:00
pool = tuple(iterable)
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61062,61066,61068,61070,61081-61095 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61081 | neal.norwitz | 2008-02-26 09:04:59 +0100 (Tue, 26 Feb 2008) | 7 lines Speed up this test by about 99%. Remove sleeps and replace with events. (This may fail on some slow platforms, but we can fix those cases which should be relatively isolated and easier to find now.) Move two test cases that didn't require a server to be started to a separate TestCase. These tests were taking 3 seconds which is what the timeout was set to. ........ r61082 | christian.heimes | 2008-02-26 09:18:11 +0100 (Tue, 26 Feb 2008) | 1 line The contains function raised a gcc warning. The new code is copied straight from py3k. ........ r61084 | neal.norwitz | 2008-02-26 09:21:28 +0100 (Tue, 26 Feb 2008) | 3 lines Add a timing flag to Trace so you can see where slowness occurs like waiting for socket timeouts in test_smtplib :-). ........ r61086 | christian.heimes | 2008-02-26 18:23:51 +0100 (Tue, 26 Feb 2008) | 3 lines Patch #1691070 from Roger Upole: Speed up PyArg_ParseTupleAndKeywords() and improve error msg My tests don't show the promised speed up of 10%. The code is as fast as the old code for simple cases and slightly faster for complex cases with several of args and kwargs. But the patch simplifies the code, too. ........ r61087 | georg.brandl | 2008-02-26 20:13:45 +0100 (Tue, 26 Feb 2008) | 2 lines #2194: fix some typos. ........ r61088 | raymond.hettinger | 2008-02-27 00:40:50 +0100 (Wed, 27 Feb 2008) | 1 line Add itertools.combinations(). ........ r61089 | raymond.hettinger | 2008-02-27 02:08:04 +0100 (Wed, 27 Feb 2008) | 1 line One too many decrefs. ........ r61090 | raymond.hettinger | 2008-02-27 02:08:30 +0100 (Wed, 27 Feb 2008) | 1 line Larger test range ........ r61091 | raymond.hettinger | 2008-02-27 02:44:34 +0100 (Wed, 27 Feb 2008) | 1 line Simply the sample code for combinations(). ........
2008-02-28 07:19:05 -04:00
n = len(pool)
if r > n:
return
indices = list(range(r))
Merged revisions 61143-61144,61146-61147,61150-61151,61157,61165-61168,61170-61173,61176-61177,61183 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61143 | barry.warsaw | 2008-03-01 03:23:38 +0100 (Sat, 01 Mar 2008) | 2 lines Bump to version 2.6a1 ........ r61144 | barry.warsaw | 2008-03-01 03:26:42 +0100 (Sat, 01 Mar 2008) | 1 line bump idle version number ........ r61146 | fred.drake | 2008-03-01 03:45:07 +0100 (Sat, 01 Mar 2008) | 2 lines fix typo ........ r61147 | barry.warsaw | 2008-03-01 03:53:36 +0100 (Sat, 01 Mar 2008) | 1 line Add date to NEWS ........ r61150 | barry.warsaw | 2008-03-01 04:00:52 +0100 (Sat, 01 Mar 2008) | 1 line Give IDLE a release date ........ r61151 | barry.warsaw | 2008-03-01 04:15:20 +0100 (Sat, 01 Mar 2008) | 1 line More copyright year and version number bumps ........ r61157 | barry.warsaw | 2008-03-01 18:11:41 +0100 (Sat, 01 Mar 2008) | 2 lines Set things up for 2.6a2. ........ r61165 | georg.brandl | 2008-03-02 07:28:16 +0100 (Sun, 02 Mar 2008) | 2 lines It's 2.6 now. ........ r61166 | georg.brandl | 2008-03-02 07:32:32 +0100 (Sun, 02 Mar 2008) | 2 lines Update year. ........ r61167 | georg.brandl | 2008-03-02 07:44:08 +0100 (Sun, 02 Mar 2008) | 2 lines Make patchlevel print out the release if called as a script. ........ r61168 | georg.brandl | 2008-03-02 07:45:40 +0100 (Sun, 02 Mar 2008) | 2 lines New default basename for HTML help files. ........ r61170 | raymond.hettinger | 2008-03-02 11:59:31 +0100 (Sun, 02 Mar 2008) | 1 line Finish-up docs for combinations() and permutations() in itertools. ........ r61171 | raymond.hettinger | 2008-03-02 12:17:51 +0100 (Sun, 02 Mar 2008) | 1 line Tighten example code. ........ r61172 | raymond.hettinger | 2008-03-02 12:57:16 +0100 (Sun, 02 Mar 2008) | 1 line Simplify code for itertools.product(). ........ r61173 | raymond.hettinger | 2008-03-02 13:02:19 +0100 (Sun, 02 Mar 2008) | 1 line Handle 0-tuples which can be singletons. ........ r61176 | georg.brandl | 2008-03-02 14:41:39 +0100 (Sun, 02 Mar 2008) | 2 lines Make clear that the constants are strings. ........ r61177 | georg.brandl | 2008-03-02 15:15:04 +0100 (Sun, 02 Mar 2008) | 2 lines Fix factual error. ........ r61183 | gregory.p.smith | 2008-03-02 21:00:53 +0100 (Sun, 02 Mar 2008) | 4 lines Modify import of test_support so that the code can also be used with a stand alone distribution of bsddb that includes its own small copy of test_support for the needed functionality on older pythons. ........
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yield tuple(pool[i] for i in indices)
2009-02-18 16:56:51 -04:00
while True:
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61062,61066,61068,61070,61081-61095 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61081 | neal.norwitz | 2008-02-26 09:04:59 +0100 (Tue, 26 Feb 2008) | 7 lines Speed up this test by about 99%. Remove sleeps and replace with events. (This may fail on some slow platforms, but we can fix those cases which should be relatively isolated and easier to find now.) Move two test cases that didn't require a server to be started to a separate TestCase. These tests were taking 3 seconds which is what the timeout was set to. ........ r61082 | christian.heimes | 2008-02-26 09:18:11 +0100 (Tue, 26 Feb 2008) | 1 line The contains function raised a gcc warning. The new code is copied straight from py3k. ........ r61084 | neal.norwitz | 2008-02-26 09:21:28 +0100 (Tue, 26 Feb 2008) | 3 lines Add a timing flag to Trace so you can see where slowness occurs like waiting for socket timeouts in test_smtplib :-). ........ r61086 | christian.heimes | 2008-02-26 18:23:51 +0100 (Tue, 26 Feb 2008) | 3 lines Patch #1691070 from Roger Upole: Speed up PyArg_ParseTupleAndKeywords() and improve error msg My tests don't show the promised speed up of 10%. The code is as fast as the old code for simple cases and slightly faster for complex cases with several of args and kwargs. But the patch simplifies the code, too. ........ r61087 | georg.brandl | 2008-02-26 20:13:45 +0100 (Tue, 26 Feb 2008) | 2 lines #2194: fix some typos. ........ r61088 | raymond.hettinger | 2008-02-27 00:40:50 +0100 (Wed, 27 Feb 2008) | 1 line Add itertools.combinations(). ........ r61089 | raymond.hettinger | 2008-02-27 02:08:04 +0100 (Wed, 27 Feb 2008) | 1 line One too many decrefs. ........ r61090 | raymond.hettinger | 2008-02-27 02:08:30 +0100 (Wed, 27 Feb 2008) | 1 line Larger test range ........ r61091 | raymond.hettinger | 2008-02-27 02:44:34 +0100 (Wed, 27 Feb 2008) | 1 line Simply the sample code for combinations(). ........
2008-02-28 07:19:05 -04:00
for i in reversed(range(r)):
Merged revisions 61143-61144,61146-61147,61150-61151,61157,61165-61168,61170-61173,61176-61177,61183 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61143 | barry.warsaw | 2008-03-01 03:23:38 +0100 (Sat, 01 Mar 2008) | 2 lines Bump to version 2.6a1 ........ r61144 | barry.warsaw | 2008-03-01 03:26:42 +0100 (Sat, 01 Mar 2008) | 1 line bump idle version number ........ r61146 | fred.drake | 2008-03-01 03:45:07 +0100 (Sat, 01 Mar 2008) | 2 lines fix typo ........ r61147 | barry.warsaw | 2008-03-01 03:53:36 +0100 (Sat, 01 Mar 2008) | 1 line Add date to NEWS ........ r61150 | barry.warsaw | 2008-03-01 04:00:52 +0100 (Sat, 01 Mar 2008) | 1 line Give IDLE a release date ........ r61151 | barry.warsaw | 2008-03-01 04:15:20 +0100 (Sat, 01 Mar 2008) | 1 line More copyright year and version number bumps ........ r61157 | barry.warsaw | 2008-03-01 18:11:41 +0100 (Sat, 01 Mar 2008) | 2 lines Set things up for 2.6a2. ........ r61165 | georg.brandl | 2008-03-02 07:28:16 +0100 (Sun, 02 Mar 2008) | 2 lines It's 2.6 now. ........ r61166 | georg.brandl | 2008-03-02 07:32:32 +0100 (Sun, 02 Mar 2008) | 2 lines Update year. ........ r61167 | georg.brandl | 2008-03-02 07:44:08 +0100 (Sun, 02 Mar 2008) | 2 lines Make patchlevel print out the release if called as a script. ........ r61168 | georg.brandl | 2008-03-02 07:45:40 +0100 (Sun, 02 Mar 2008) | 2 lines New default basename for HTML help files. ........ r61170 | raymond.hettinger | 2008-03-02 11:59:31 +0100 (Sun, 02 Mar 2008) | 1 line Finish-up docs for combinations() and permutations() in itertools. ........ r61171 | raymond.hettinger | 2008-03-02 12:17:51 +0100 (Sun, 02 Mar 2008) | 1 line Tighten example code. ........ r61172 | raymond.hettinger | 2008-03-02 12:57:16 +0100 (Sun, 02 Mar 2008) | 1 line Simplify code for itertools.product(). ........ r61173 | raymond.hettinger | 2008-03-02 13:02:19 +0100 (Sun, 02 Mar 2008) | 1 line Handle 0-tuples which can be singletons. ........ r61176 | georg.brandl | 2008-03-02 14:41:39 +0100 (Sun, 02 Mar 2008) | 2 lines Make clear that the constants are strings. ........ r61177 | georg.brandl | 2008-03-02 15:15:04 +0100 (Sun, 02 Mar 2008) | 2 lines Fix factual error. ........ r61183 | gregory.p.smith | 2008-03-02 21:00:53 +0100 (Sun, 02 Mar 2008) | 4 lines Modify import of test_support so that the code can also be used with a stand alone distribution of bsddb that includes its own small copy of test_support for the needed functionality on older pythons. ........
2008-03-02 18:46:37 -04:00
if indices[i] != i + n - r:
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61064,61066-61080 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61063 | andrew.kuchling | 2008-02-25 17:29:19 +0100 (Mon, 25 Feb 2008) | 1 line Move .setupterm() output so that we don't try to call endwin() if it fails ........ r61064 | andrew.kuchling | 2008-02-25 17:29:58 +0100 (Mon, 25 Feb 2008) | 1 line Use file descriptor for real stdout ........ r61067 | facundo.batista | 2008-02-25 19:06:00 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2117. Update compiler module to handle class decorators. Thanks Thomas Herve ........ r61069 | georg.brandl | 2008-02-25 21:17:56 +0100 (Mon, 25 Feb 2008) | 2 lines Rename sphinx.addons to sphinx.ext. ........ r61071 | georg.brandl | 2008-02-25 21:20:45 +0100 (Mon, 25 Feb 2008) | 2 lines Revert r61029. ........ r61072 | facundo.batista | 2008-02-25 23:33:55 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2168. gdbm and dbm needs to be iterable; this fixes a failure in the shelve module. Thanks Thomas Herve. ........ r61073 | raymond.hettinger | 2008-02-25 23:42:32 +0100 (Mon, 25 Feb 2008) | 1 line Make sure the itertools filter functions give the same performance for func=bool as func=None. ........ r61074 | raymond.hettinger | 2008-02-26 00:17:41 +0100 (Tue, 26 Feb 2008) | 1 line Revert part of r60927 which made invalid assumptions about the API offered by db modules. ........ r61075 | facundo.batista | 2008-02-26 00:46:02 +0100 (Tue, 26 Feb 2008) | 3 lines Coerced PyBool_Type to be able to compare it. ........ r61076 | raymond.hettinger | 2008-02-26 03:46:54 +0100 (Tue, 26 Feb 2008) | 1 line Docs for itertools.combinations(). Implementation in forthcoming checkin. ........ r61077 | neal.norwitz | 2008-02-26 05:50:37 +0100 (Tue, 26 Feb 2008) | 3 lines Don't use a hard coded port. This test could hang/fail if the port is in use. Speed this test up by avoiding a sleep and using the event. ........ r61078 | neal.norwitz | 2008-02-26 06:12:50 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61079 | neal.norwitz | 2008-02-26 06:23:51 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61080 | georg.brandl | 2008-02-26 07:40:10 +0100 (Tue, 26 Feb 2008) | 2 lines Banish tab. ........
2008-02-26 04:18:30 -04:00
break
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61062,61066,61068,61070,61081-61095 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61081 | neal.norwitz | 2008-02-26 09:04:59 +0100 (Tue, 26 Feb 2008) | 7 lines Speed up this test by about 99%. Remove sleeps and replace with events. (This may fail on some slow platforms, but we can fix those cases which should be relatively isolated and easier to find now.) Move two test cases that didn't require a server to be started to a separate TestCase. These tests were taking 3 seconds which is what the timeout was set to. ........ r61082 | christian.heimes | 2008-02-26 09:18:11 +0100 (Tue, 26 Feb 2008) | 1 line The contains function raised a gcc warning. The new code is copied straight from py3k. ........ r61084 | neal.norwitz | 2008-02-26 09:21:28 +0100 (Tue, 26 Feb 2008) | 3 lines Add a timing flag to Trace so you can see where slowness occurs like waiting for socket timeouts in test_smtplib :-). ........ r61086 | christian.heimes | 2008-02-26 18:23:51 +0100 (Tue, 26 Feb 2008) | 3 lines Patch #1691070 from Roger Upole: Speed up PyArg_ParseTupleAndKeywords() and improve error msg My tests don't show the promised speed up of 10%. The code is as fast as the old code for simple cases and slightly faster for complex cases with several of args and kwargs. But the patch simplifies the code, too. ........ r61087 | georg.brandl | 2008-02-26 20:13:45 +0100 (Tue, 26 Feb 2008) | 2 lines #2194: fix some typos. ........ r61088 | raymond.hettinger | 2008-02-27 00:40:50 +0100 (Wed, 27 Feb 2008) | 1 line Add itertools.combinations(). ........ r61089 | raymond.hettinger | 2008-02-27 02:08:04 +0100 (Wed, 27 Feb 2008) | 1 line One too many decrefs. ........ r61090 | raymond.hettinger | 2008-02-27 02:08:30 +0100 (Wed, 27 Feb 2008) | 1 line Larger test range ........ r61091 | raymond.hettinger | 2008-02-27 02:44:34 +0100 (Wed, 27 Feb 2008) | 1 line Simply the sample code for combinations(). ........
2008-02-28 07:19:05 -04:00
else:
return
Merged revisions 61143-61144,61146-61147,61150-61151,61157,61165-61168,61170-61173,61176-61177,61183 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61143 | barry.warsaw | 2008-03-01 03:23:38 +0100 (Sat, 01 Mar 2008) | 2 lines Bump to version 2.6a1 ........ r61144 | barry.warsaw | 2008-03-01 03:26:42 +0100 (Sat, 01 Mar 2008) | 1 line bump idle version number ........ r61146 | fred.drake | 2008-03-01 03:45:07 +0100 (Sat, 01 Mar 2008) | 2 lines fix typo ........ r61147 | barry.warsaw | 2008-03-01 03:53:36 +0100 (Sat, 01 Mar 2008) | 1 line Add date to NEWS ........ r61150 | barry.warsaw | 2008-03-01 04:00:52 +0100 (Sat, 01 Mar 2008) | 1 line Give IDLE a release date ........ r61151 | barry.warsaw | 2008-03-01 04:15:20 +0100 (Sat, 01 Mar 2008) | 1 line More copyright year and version number bumps ........ r61157 | barry.warsaw | 2008-03-01 18:11:41 +0100 (Sat, 01 Mar 2008) | 2 lines Set things up for 2.6a2. ........ r61165 | georg.brandl | 2008-03-02 07:28:16 +0100 (Sun, 02 Mar 2008) | 2 lines It's 2.6 now. ........ r61166 | georg.brandl | 2008-03-02 07:32:32 +0100 (Sun, 02 Mar 2008) | 2 lines Update year. ........ r61167 | georg.brandl | 2008-03-02 07:44:08 +0100 (Sun, 02 Mar 2008) | 2 lines Make patchlevel print out the release if called as a script. ........ r61168 | georg.brandl | 2008-03-02 07:45:40 +0100 (Sun, 02 Mar 2008) | 2 lines New default basename for HTML help files. ........ r61170 | raymond.hettinger | 2008-03-02 11:59:31 +0100 (Sun, 02 Mar 2008) | 1 line Finish-up docs for combinations() and permutations() in itertools. ........ r61171 | raymond.hettinger | 2008-03-02 12:17:51 +0100 (Sun, 02 Mar 2008) | 1 line Tighten example code. ........ r61172 | raymond.hettinger | 2008-03-02 12:57:16 +0100 (Sun, 02 Mar 2008) | 1 line Simplify code for itertools.product(). ........ r61173 | raymond.hettinger | 2008-03-02 13:02:19 +0100 (Sun, 02 Mar 2008) | 1 line Handle 0-tuples which can be singletons. ........ r61176 | georg.brandl | 2008-03-02 14:41:39 +0100 (Sun, 02 Mar 2008) | 2 lines Make clear that the constants are strings. ........ r61177 | georg.brandl | 2008-03-02 15:15:04 +0100 (Sun, 02 Mar 2008) | 2 lines Fix factual error. ........ r61183 | gregory.p.smith | 2008-03-02 21:00:53 +0100 (Sun, 02 Mar 2008) | 4 lines Modify import of test_support so that the code can also be used with a stand alone distribution of bsddb that includes its own small copy of test_support for the needed functionality on older pythons. ........
2008-03-02 18:46:37 -04:00
indices[i] += 1
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61062,61066,61068,61070,61081-61095 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61081 | neal.norwitz | 2008-02-26 09:04:59 +0100 (Tue, 26 Feb 2008) | 7 lines Speed up this test by about 99%. Remove sleeps and replace with events. (This may fail on some slow platforms, but we can fix those cases which should be relatively isolated and easier to find now.) Move two test cases that didn't require a server to be started to a separate TestCase. These tests were taking 3 seconds which is what the timeout was set to. ........ r61082 | christian.heimes | 2008-02-26 09:18:11 +0100 (Tue, 26 Feb 2008) | 1 line The contains function raised a gcc warning. The new code is copied straight from py3k. ........ r61084 | neal.norwitz | 2008-02-26 09:21:28 +0100 (Tue, 26 Feb 2008) | 3 lines Add a timing flag to Trace so you can see where slowness occurs like waiting for socket timeouts in test_smtplib :-). ........ r61086 | christian.heimes | 2008-02-26 18:23:51 +0100 (Tue, 26 Feb 2008) | 3 lines Patch #1691070 from Roger Upole: Speed up PyArg_ParseTupleAndKeywords() and improve error msg My tests don't show the promised speed up of 10%. The code is as fast as the old code for simple cases and slightly faster for complex cases with several of args and kwargs. But the patch simplifies the code, too. ........ r61087 | georg.brandl | 2008-02-26 20:13:45 +0100 (Tue, 26 Feb 2008) | 2 lines #2194: fix some typos. ........ r61088 | raymond.hettinger | 2008-02-27 00:40:50 +0100 (Wed, 27 Feb 2008) | 1 line Add itertools.combinations(). ........ r61089 | raymond.hettinger | 2008-02-27 02:08:04 +0100 (Wed, 27 Feb 2008) | 1 line One too many decrefs. ........ r61090 | raymond.hettinger | 2008-02-27 02:08:30 +0100 (Wed, 27 Feb 2008) | 1 line Larger test range ........ r61091 | raymond.hettinger | 2008-02-27 02:44:34 +0100 (Wed, 27 Feb 2008) | 1 line Simply the sample code for combinations(). ........
2008-02-28 07:19:05 -04:00
for j in range(i+1, r):
Merged revisions 61143-61144,61146-61147,61150-61151,61157,61165-61168,61170-61173,61176-61177,61183 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61143 | barry.warsaw | 2008-03-01 03:23:38 +0100 (Sat, 01 Mar 2008) | 2 lines Bump to version 2.6a1 ........ r61144 | barry.warsaw | 2008-03-01 03:26:42 +0100 (Sat, 01 Mar 2008) | 1 line bump idle version number ........ r61146 | fred.drake | 2008-03-01 03:45:07 +0100 (Sat, 01 Mar 2008) | 2 lines fix typo ........ r61147 | barry.warsaw | 2008-03-01 03:53:36 +0100 (Sat, 01 Mar 2008) | 1 line Add date to NEWS ........ r61150 | barry.warsaw | 2008-03-01 04:00:52 +0100 (Sat, 01 Mar 2008) | 1 line Give IDLE a release date ........ r61151 | barry.warsaw | 2008-03-01 04:15:20 +0100 (Sat, 01 Mar 2008) | 1 line More copyright year and version number bumps ........ r61157 | barry.warsaw | 2008-03-01 18:11:41 +0100 (Sat, 01 Mar 2008) | 2 lines Set things up for 2.6a2. ........ r61165 | georg.brandl | 2008-03-02 07:28:16 +0100 (Sun, 02 Mar 2008) | 2 lines It's 2.6 now. ........ r61166 | georg.brandl | 2008-03-02 07:32:32 +0100 (Sun, 02 Mar 2008) | 2 lines Update year. ........ r61167 | georg.brandl | 2008-03-02 07:44:08 +0100 (Sun, 02 Mar 2008) | 2 lines Make patchlevel print out the release if called as a script. ........ r61168 | georg.brandl | 2008-03-02 07:45:40 +0100 (Sun, 02 Mar 2008) | 2 lines New default basename for HTML help files. ........ r61170 | raymond.hettinger | 2008-03-02 11:59:31 +0100 (Sun, 02 Mar 2008) | 1 line Finish-up docs for combinations() and permutations() in itertools. ........ r61171 | raymond.hettinger | 2008-03-02 12:17:51 +0100 (Sun, 02 Mar 2008) | 1 line Tighten example code. ........ r61172 | raymond.hettinger | 2008-03-02 12:57:16 +0100 (Sun, 02 Mar 2008) | 1 line Simplify code for itertools.product(). ........ r61173 | raymond.hettinger | 2008-03-02 13:02:19 +0100 (Sun, 02 Mar 2008) | 1 line Handle 0-tuples which can be singletons. ........ r61176 | georg.brandl | 2008-03-02 14:41:39 +0100 (Sun, 02 Mar 2008) | 2 lines Make clear that the constants are strings. ........ r61177 | georg.brandl | 2008-03-02 15:15:04 +0100 (Sun, 02 Mar 2008) | 2 lines Fix factual error. ........ r61183 | gregory.p.smith | 2008-03-02 21:00:53 +0100 (Sun, 02 Mar 2008) | 4 lines Modify import of test_support so that the code can also be used with a stand alone distribution of bsddb that includes its own small copy of test_support for the needed functionality on older pythons. ........
2008-03-02 18:46:37 -04:00
indices[j] = indices[j-1] + 1
yield tuple(pool[i] for i in indices)
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61064,61066-61080 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61063 | andrew.kuchling | 2008-02-25 17:29:19 +0100 (Mon, 25 Feb 2008) | 1 line Move .setupterm() output so that we don't try to call endwin() if it fails ........ r61064 | andrew.kuchling | 2008-02-25 17:29:58 +0100 (Mon, 25 Feb 2008) | 1 line Use file descriptor for real stdout ........ r61067 | facundo.batista | 2008-02-25 19:06:00 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2117. Update compiler module to handle class decorators. Thanks Thomas Herve ........ r61069 | georg.brandl | 2008-02-25 21:17:56 +0100 (Mon, 25 Feb 2008) | 2 lines Rename sphinx.addons to sphinx.ext. ........ r61071 | georg.brandl | 2008-02-25 21:20:45 +0100 (Mon, 25 Feb 2008) | 2 lines Revert r61029. ........ r61072 | facundo.batista | 2008-02-25 23:33:55 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2168. gdbm and dbm needs to be iterable; this fixes a failure in the shelve module. Thanks Thomas Herve. ........ r61073 | raymond.hettinger | 2008-02-25 23:42:32 +0100 (Mon, 25 Feb 2008) | 1 line Make sure the itertools filter functions give the same performance for func=bool as func=None. ........ r61074 | raymond.hettinger | 2008-02-26 00:17:41 +0100 (Tue, 26 Feb 2008) | 1 line Revert part of r60927 which made invalid assumptions about the API offered by db modules. ........ r61075 | facundo.batista | 2008-02-26 00:46:02 +0100 (Tue, 26 Feb 2008) | 3 lines Coerced PyBool_Type to be able to compare it. ........ r61076 | raymond.hettinger | 2008-02-26 03:46:54 +0100 (Tue, 26 Feb 2008) | 1 line Docs for itertools.combinations(). Implementation in forthcoming checkin. ........ r61077 | neal.norwitz | 2008-02-26 05:50:37 +0100 (Tue, 26 Feb 2008) | 3 lines Don't use a hard coded port. This test could hang/fail if the port is in use. Speed this test up by avoiding a sleep and using the event. ........ r61078 | neal.norwitz | 2008-02-26 06:12:50 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61079 | neal.norwitz | 2008-02-26 06:23:51 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61080 | georg.brandl | 2008-02-26 07:40:10 +0100 (Tue, 26 Feb 2008) | 2 lines Banish tab. ........
2008-02-26 04:18:30 -04:00
The code for :func:`combinations` can be also expressed as a subsequence
of :func:`permutations` after filtering entries where the elements are not
in sorted order (according to their position in the input pool)::
Merged revisions 61209-61214,61217-61222,61224-61226,61233-61237 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61209 | georg.brandl | 2008-03-03 21:37:55 +0100 (Mon, 03 Mar 2008) | 2 lines There are now sixteen isfoo functions. ........ r61210 | georg.brandl | 2008-03-03 21:39:00 +0100 (Mon, 03 Mar 2008) | 2 lines 15 -> 16, the 2nd ........ r61211 | georg.brandl | 2008-03-03 22:22:47 +0100 (Mon, 03 Mar 2008) | 2 lines Actually import itertools. ........ r61212 | georg.brandl | 2008-03-03 22:31:50 +0100 (Mon, 03 Mar 2008) | 2 lines Expand a bit on genexp scopes. ........ r61213 | raymond.hettinger | 2008-03-03 23:04:55 +0100 (Mon, 03 Mar 2008) | 1 line Remove dependency on itertools -- a simple genexp suffices. ........ r61214 | raymond.hettinger | 2008-03-03 23:19:58 +0100 (Mon, 03 Mar 2008) | 1 line Issue 2226: Callable checked for the wrong abstract method. ........ r61217 | andrew.kuchling | 2008-03-04 01:40:32 +0100 (Tue, 04 Mar 2008) | 1 line Typo fix ........ r61218 | andrew.kuchling | 2008-03-04 02:30:10 +0100 (Tue, 04 Mar 2008) | 1 line Grammar fix; markup fix ........ r61219 | andrew.kuchling | 2008-03-04 02:47:38 +0100 (Tue, 04 Mar 2008) | 1 line Fix sentence fragment ........ r61220 | andrew.kuchling | 2008-03-04 02:48:26 +0100 (Tue, 04 Mar 2008) | 1 line Typo fix ........ r61221 | andrew.kuchling | 2008-03-04 02:49:37 +0100 (Tue, 04 Mar 2008) | 1 line Add versionadded tags ........ r61222 | andrew.kuchling | 2008-03-04 02:50:32 +0100 (Tue, 04 Mar 2008) | 1 line Thesis night results: add various items ........ r61224 | raymond.hettinger | 2008-03-04 05:17:08 +0100 (Tue, 04 Mar 2008) | 1 line Beef-up docs and tests for itertools. Fix-up end-case for product(). ........ r61225 | georg.brandl | 2008-03-04 08:25:54 +0100 (Tue, 04 Mar 2008) | 2 lines Fix some patch attributions. ........ r61226 | georg.brandl | 2008-03-04 08:33:30 +0100 (Tue, 04 Mar 2008) | 2 lines #2230: document that PyArg_* leaves addresses alone on error. ........ r61233 | neal.norwitz | 2008-03-04 17:22:46 +0100 (Tue, 04 Mar 2008) | 3 lines Close the file before trying to remove the directory so it works on Windows. As reported by Trent Nelson on python-dev. ........ r61234 | thomas.heller | 2008-03-04 21:09:11 +0100 (Tue, 04 Mar 2008) | 9 lines Merged changes from libffi3-branch. The bundled libffi copy is now in sync with the recently released libffi3.0.4 version, apart from some small changes to Modules/_ctypes/libffi/configure.ac. I gave up on using libffi3 files on os x. Instead, static configuration with files from pyobjc is used. ........ r61235 | thomas.heller | 2008-03-04 21:21:42 +0100 (Tue, 04 Mar 2008) | 1 line Try to fix the build for PY_LINUX. ........ r61236 | fred.drake | 2008-03-04 22:14:04 +0100 (Tue, 04 Mar 2008) | 2 lines fix typo ........ r61237 | raymond.hettinger | 2008-03-04 23:29:44 +0100 (Tue, 04 Mar 2008) | 1 line Fix refleak in chain(). ........
2008-03-04 19:39:23 -04:00
def combinations(iterable, r):
pool = tuple(iterable)
n = len(pool)
for indices in permutations(range(n), r):
if sorted(indices) == list(indices):
yield tuple(pool[i] for i in indices)
The number of items returned is ``n! / r! / (n-r)!`` when ``0 <= r <= n``
or zero when ``r > n``.
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61064,61066-61080 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61063 | andrew.kuchling | 2008-02-25 17:29:19 +0100 (Mon, 25 Feb 2008) | 1 line Move .setupterm() output so that we don't try to call endwin() if it fails ........ r61064 | andrew.kuchling | 2008-02-25 17:29:58 +0100 (Mon, 25 Feb 2008) | 1 line Use file descriptor for real stdout ........ r61067 | facundo.batista | 2008-02-25 19:06:00 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2117. Update compiler module to handle class decorators. Thanks Thomas Herve ........ r61069 | georg.brandl | 2008-02-25 21:17:56 +0100 (Mon, 25 Feb 2008) | 2 lines Rename sphinx.addons to sphinx.ext. ........ r61071 | georg.brandl | 2008-02-25 21:20:45 +0100 (Mon, 25 Feb 2008) | 2 lines Revert r61029. ........ r61072 | facundo.batista | 2008-02-25 23:33:55 +0100 (Mon, 25 Feb 2008) | 4 lines Issue 2168. gdbm and dbm needs to be iterable; this fixes a failure in the shelve module. Thanks Thomas Herve. ........ r61073 | raymond.hettinger | 2008-02-25 23:42:32 +0100 (Mon, 25 Feb 2008) | 1 line Make sure the itertools filter functions give the same performance for func=bool as func=None. ........ r61074 | raymond.hettinger | 2008-02-26 00:17:41 +0100 (Tue, 26 Feb 2008) | 1 line Revert part of r60927 which made invalid assumptions about the API offered by db modules. ........ r61075 | facundo.batista | 2008-02-26 00:46:02 +0100 (Tue, 26 Feb 2008) | 3 lines Coerced PyBool_Type to be able to compare it. ........ r61076 | raymond.hettinger | 2008-02-26 03:46:54 +0100 (Tue, 26 Feb 2008) | 1 line Docs for itertools.combinations(). Implementation in forthcoming checkin. ........ r61077 | neal.norwitz | 2008-02-26 05:50:37 +0100 (Tue, 26 Feb 2008) | 3 lines Don't use a hard coded port. This test could hang/fail if the port is in use. Speed this test up by avoiding a sleep and using the event. ........ r61078 | neal.norwitz | 2008-02-26 06:12:50 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61079 | neal.norwitz | 2008-02-26 06:23:51 +0100 (Tue, 26 Feb 2008) | 1 line Whitespace normalization ........ r61080 | georg.brandl | 2008-02-26 07:40:10 +0100 (Tue, 26 Feb 2008) | 2 lines Banish tab. ........
2008-02-26 04:18:30 -04:00
.. function:: combinations_with_replacement(iterable, r)
Return *r* length subsequences of elements from the input *iterable*
allowing individual elements to be repeated more than once.
Combinations are emitted in lexicographic sort order. So, if the
input *iterable* is sorted, the combination tuples will be produced
in sorted order.
Elements are treated as unique based on their position, not on their
value. So if the input elements are unique, the generated combinations
will also be unique.
Roughly equivalent to::
def combinations_with_replacement(iterable, r):
# combinations_with_replacement('ABC', 2) --> AA AB AC BB BC CC
pool = tuple(iterable)
n = len(pool)
if not n and r:
return
indices = [0] * r
yield tuple(pool[i] for i in indices)
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while True:
for i in reversed(range(r)):
if indices[i] != n - 1:
break
else:
return
indices[i:] = [indices[i] + 1] * (r - i)
yield tuple(pool[i] for i in indices)
The code for :func:`combinations_with_replacement` can be also expressed as
a subsequence of :func:`product` after filtering entries where the elements
are not in sorted order (according to their position in the input pool)::
def combinations_with_replacement(iterable, r):
pool = tuple(iterable)
n = len(pool)
for indices in product(range(n), repeat=r):
if sorted(indices) == list(indices):
yield tuple(pool[i] for i in indices)
The number of items returned is ``(n+r-1)! / r! / (n-1)!`` when ``n > 0``.
.. versionadded:: 3.1
.. function:: compress(data, selectors)
Make an iterator that filters elements from *data* returning only those that
have a corresponding element in *selectors* that evaluates to ``True``.
Stops when either the *data* or *selectors* iterables has been exhausted.
Roughly equivalent to::
def compress(data, selectors):
# compress('ABCDEF', [1,0,1,0,1,1]) --> A C E F
return (d for d, s in zip(data, selectors) if s)
.. versionadded:: 3.1
.. function:: count(start=0, step=1)
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Make an iterator that returns evenly spaced values starting with number *start*. Often
used as an argument to :func:`map` to generate consecutive data points.
Also, used with :func:`zip` to add sequence numbers. Roughly equivalent to::
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def count(start=0, step=1):
# count(10) --> 10 11 12 13 14 ...
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# count(2.5, 0.5) -> 2.5 3.0 3.5 ...
n = start
while True:
yield n
n += step
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When counting with floating point numbers, better accuracy can sometimes be
achieved by substituting multiplicative code such as: ``(start + step * i
for i in count())``.
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.. versionchanged:: 3.1
Added *step* argument and allowed non-integer arguments.
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.. function:: cycle(iterable)
Make an iterator returning elements from the iterable and saving a copy of each.
When the iterable is exhausted, return elements from the saved copy. Repeats
indefinitely. Roughly equivalent to::
def cycle(iterable):
# cycle('ABCD') --> A B C D A B C D A B C D ...
saved = []
for element in iterable:
yield element
saved.append(element)
while saved:
for element in saved:
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yield element
Note, this member of the toolkit may require significant auxiliary storage
(depending on the length of the iterable).
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.. function:: dropwhile(predicate, iterable)
Make an iterator that drops elements from the iterable as long as the predicate
is true; afterwards, returns every element. Note, the iterator does not produce
*any* output until the predicate first becomes false, so it may have a lengthy
start-up time. Roughly equivalent to::
def dropwhile(predicate, iterable):
# dropwhile(lambda x: x<5, [1,4,6,4,1]) --> 6 4 1
iterable = iter(iterable)
for x in iterable:
if not predicate(x):
yield x
break
for x in iterable:
yield x
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.. function:: filterfalse(predicate, iterable)
Make an iterator that filters elements from iterable returning only those for
which the predicate is ``False``. If *predicate* is ``None``, return the items
that are false. Roughly equivalent to::
def filterfalse(predicate, iterable):
# filterfalse(lambda x: x%2, range(10)) --> 0 2 4 6 8
if predicate is None:
predicate = bool
for x in iterable:
if not predicate(x):
yield x
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.. function:: groupby(iterable, key=None)
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Make an iterator that returns consecutive keys and groups from the *iterable*.
The *key* is a function computing a key value for each element. If not
specified or is ``None``, *key* defaults to an identity function and returns
the element unchanged. Generally, the iterable needs to already be sorted on
the same key function.
The operation of :func:`groupby` is similar to the ``uniq`` filter in Unix. It
generates a break or new group every time the value of the key function changes
(which is why it is usually necessary to have sorted the data using the same key
function). That behavior differs from SQL's GROUP BY which aggregates common
elements regardless of their input order.
The returned group is itself an iterator that shares the underlying iterable
with :func:`groupby`. Because the source is shared, when the :func:`groupby`
object is advanced, the previous group is no longer visible. So, if that data
is needed later, it should be stored as a list::
groups = []
uniquekeys = []
data = sorted(data, key=keyfunc)
for k, g in groupby(data, keyfunc):
groups.append(list(g)) # Store group iterator as a list
uniquekeys.append(k)
:func:`groupby` is roughly equivalent to::
class groupby:
# [k for k, g in groupby('AAAABBBCCDAABBB')] --> A B C D A B
# [list(g) for k, g in groupby('AAAABBBCCD')] --> AAAA BBB CC D
def __init__(self, iterable, key=None):
if key is None:
key = lambda x: x
self.keyfunc = key
self.it = iter(iterable)
self.tgtkey = self.currkey = self.currvalue = object()
def __iter__(self):
return self
def __next__(self):
while self.currkey == self.tgtkey:
self.currvalue = next(self.it) # Exit on StopIteration
self.currkey = self.keyfunc(self.currvalue)
self.tgtkey = self.currkey
return (self.currkey, self._grouper(self.tgtkey))
def _grouper(self, tgtkey):
while self.currkey == tgtkey:
yield self.currvalue
try:
self.currvalue = next(self.it)
except StopIteration:
return
self.currkey = self.keyfunc(self.currvalue)
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.. function:: islice(iterable, stop)
islice(iterable, start, stop[, step])
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Make an iterator that returns selected elements from the iterable. If *start* is
non-zero, then elements from the iterable are skipped until start is reached.
Afterward, elements are returned consecutively unless *step* is set higher than
one which results in items being skipped. If *stop* is ``None``, then iteration
continues until the iterator is exhausted, if at all; otherwise, it stops at the
specified position. Unlike regular slicing, :func:`islice` does not support
negative values for *start*, *stop*, or *step*. Can be used to extract related
fields from data where the internal structure has been flattened (for example, a
multi-line report may list a name field on every third line). Roughly equivalent to::
def islice(iterable, *args):
# islice('ABCDEFG', 2) --> A B
# islice('ABCDEFG', 2, 4) --> C D
# islice('ABCDEFG', 2, None) --> C D E F G
# islice('ABCDEFG', 0, None, 2) --> A C E G
s = slice(*args)
it = iter(range(s.start or 0, s.stop or sys.maxsize, s.step or 1))
try:
nexti = next(it)
except StopIteration:
return
for i, element in enumerate(iterable):
if i == nexti:
yield element
nexti = next(it)
If *start* is ``None``, then iteration starts at zero. If *step* is ``None``,
then the step defaults to one.
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.. function:: permutations(iterable, r=None)
Return successive *r* length permutations of elements in the *iterable*.
If *r* is not specified or is ``None``, then *r* defaults to the length
of the *iterable* and all possible full-length permutations
are generated.
Permutations are emitted in lexicographic sort order. So, if the
input *iterable* is sorted, the permutation tuples will be produced
in sorted order.
Elements are treated as unique based on their position, not on their
value. So if the input elements are unique, there will be no repeat
values in each permutation.
Roughly equivalent to::
Merged revisions 61143-61144,61146-61147,61150-61151,61157,61165-61168,61170-61173,61176-61177,61183 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61143 | barry.warsaw | 2008-03-01 03:23:38 +0100 (Sat, 01 Mar 2008) | 2 lines Bump to version 2.6a1 ........ r61144 | barry.warsaw | 2008-03-01 03:26:42 +0100 (Sat, 01 Mar 2008) | 1 line bump idle version number ........ r61146 | fred.drake | 2008-03-01 03:45:07 +0100 (Sat, 01 Mar 2008) | 2 lines fix typo ........ r61147 | barry.warsaw | 2008-03-01 03:53:36 +0100 (Sat, 01 Mar 2008) | 1 line Add date to NEWS ........ r61150 | barry.warsaw | 2008-03-01 04:00:52 +0100 (Sat, 01 Mar 2008) | 1 line Give IDLE a release date ........ r61151 | barry.warsaw | 2008-03-01 04:15:20 +0100 (Sat, 01 Mar 2008) | 1 line More copyright year and version number bumps ........ r61157 | barry.warsaw | 2008-03-01 18:11:41 +0100 (Sat, 01 Mar 2008) | 2 lines Set things up for 2.6a2. ........ r61165 | georg.brandl | 2008-03-02 07:28:16 +0100 (Sun, 02 Mar 2008) | 2 lines It's 2.6 now. ........ r61166 | georg.brandl | 2008-03-02 07:32:32 +0100 (Sun, 02 Mar 2008) | 2 lines Update year. ........ r61167 | georg.brandl | 2008-03-02 07:44:08 +0100 (Sun, 02 Mar 2008) | 2 lines Make patchlevel print out the release if called as a script. ........ r61168 | georg.brandl | 2008-03-02 07:45:40 +0100 (Sun, 02 Mar 2008) | 2 lines New default basename for HTML help files. ........ r61170 | raymond.hettinger | 2008-03-02 11:59:31 +0100 (Sun, 02 Mar 2008) | 1 line Finish-up docs for combinations() and permutations() in itertools. ........ r61171 | raymond.hettinger | 2008-03-02 12:17:51 +0100 (Sun, 02 Mar 2008) | 1 line Tighten example code. ........ r61172 | raymond.hettinger | 2008-03-02 12:57:16 +0100 (Sun, 02 Mar 2008) | 1 line Simplify code for itertools.product(). ........ r61173 | raymond.hettinger | 2008-03-02 13:02:19 +0100 (Sun, 02 Mar 2008) | 1 line Handle 0-tuples which can be singletons. ........ r61176 | georg.brandl | 2008-03-02 14:41:39 +0100 (Sun, 02 Mar 2008) | 2 lines Make clear that the constants are strings. ........ r61177 | georg.brandl | 2008-03-02 15:15:04 +0100 (Sun, 02 Mar 2008) | 2 lines Fix factual error. ........ r61183 | gregory.p.smith | 2008-03-02 21:00:53 +0100 (Sun, 02 Mar 2008) | 4 lines Modify import of test_support so that the code can also be used with a stand alone distribution of bsddb that includes its own small copy of test_support for the needed functionality on older pythons. ........
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def permutations(iterable, r=None):
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# permutations('ABCD', 2) --> AB AC AD BA BC BD CA CB CD DA DB DC
# permutations(range(3)) --> 012 021 102 120 201 210
Merged revisions 61143-61144,61146-61147,61150-61151,61157,61165-61168,61170-61173,61176-61177,61183 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61143 | barry.warsaw | 2008-03-01 03:23:38 +0100 (Sat, 01 Mar 2008) | 2 lines Bump to version 2.6a1 ........ r61144 | barry.warsaw | 2008-03-01 03:26:42 +0100 (Sat, 01 Mar 2008) | 1 line bump idle version number ........ r61146 | fred.drake | 2008-03-01 03:45:07 +0100 (Sat, 01 Mar 2008) | 2 lines fix typo ........ r61147 | barry.warsaw | 2008-03-01 03:53:36 +0100 (Sat, 01 Mar 2008) | 1 line Add date to NEWS ........ r61150 | barry.warsaw | 2008-03-01 04:00:52 +0100 (Sat, 01 Mar 2008) | 1 line Give IDLE a release date ........ r61151 | barry.warsaw | 2008-03-01 04:15:20 +0100 (Sat, 01 Mar 2008) | 1 line More copyright year and version number bumps ........ r61157 | barry.warsaw | 2008-03-01 18:11:41 +0100 (Sat, 01 Mar 2008) | 2 lines Set things up for 2.6a2. ........ r61165 | georg.brandl | 2008-03-02 07:28:16 +0100 (Sun, 02 Mar 2008) | 2 lines It's 2.6 now. ........ r61166 | georg.brandl | 2008-03-02 07:32:32 +0100 (Sun, 02 Mar 2008) | 2 lines Update year. ........ r61167 | georg.brandl | 2008-03-02 07:44:08 +0100 (Sun, 02 Mar 2008) | 2 lines Make patchlevel print out the release if called as a script. ........ r61168 | georg.brandl | 2008-03-02 07:45:40 +0100 (Sun, 02 Mar 2008) | 2 lines New default basename for HTML help files. ........ r61170 | raymond.hettinger | 2008-03-02 11:59:31 +0100 (Sun, 02 Mar 2008) | 1 line Finish-up docs for combinations() and permutations() in itertools. ........ r61171 | raymond.hettinger | 2008-03-02 12:17:51 +0100 (Sun, 02 Mar 2008) | 1 line Tighten example code. ........ r61172 | raymond.hettinger | 2008-03-02 12:57:16 +0100 (Sun, 02 Mar 2008) | 1 line Simplify code for itertools.product(). ........ r61173 | raymond.hettinger | 2008-03-02 13:02:19 +0100 (Sun, 02 Mar 2008) | 1 line Handle 0-tuples which can be singletons. ........ r61176 | georg.brandl | 2008-03-02 14:41:39 +0100 (Sun, 02 Mar 2008) | 2 lines Make clear that the constants are strings. ........ r61177 | georg.brandl | 2008-03-02 15:15:04 +0100 (Sun, 02 Mar 2008) | 2 lines Fix factual error. ........ r61183 | gregory.p.smith | 2008-03-02 21:00:53 +0100 (Sun, 02 Mar 2008) | 4 lines Modify import of test_support so that the code can also be used with a stand alone distribution of bsddb that includes its own small copy of test_support for the needed functionality on older pythons. ........
2008-03-02 18:46:37 -04:00
pool = tuple(iterable)
n = len(pool)
r = n if r is None else r
if r > n:
return
indices = list(range(n))
cycles = list(range(n, n-r, -1))
Merged revisions 61143-61144,61146-61147,61150-61151,61157,61165-61168,61170-61173,61176-61177,61183 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61143 | barry.warsaw | 2008-03-01 03:23:38 +0100 (Sat, 01 Mar 2008) | 2 lines Bump to version 2.6a1 ........ r61144 | barry.warsaw | 2008-03-01 03:26:42 +0100 (Sat, 01 Mar 2008) | 1 line bump idle version number ........ r61146 | fred.drake | 2008-03-01 03:45:07 +0100 (Sat, 01 Mar 2008) | 2 lines fix typo ........ r61147 | barry.warsaw | 2008-03-01 03:53:36 +0100 (Sat, 01 Mar 2008) | 1 line Add date to NEWS ........ r61150 | barry.warsaw | 2008-03-01 04:00:52 +0100 (Sat, 01 Mar 2008) | 1 line Give IDLE a release date ........ r61151 | barry.warsaw | 2008-03-01 04:15:20 +0100 (Sat, 01 Mar 2008) | 1 line More copyright year and version number bumps ........ r61157 | barry.warsaw | 2008-03-01 18:11:41 +0100 (Sat, 01 Mar 2008) | 2 lines Set things up for 2.6a2. ........ r61165 | georg.brandl | 2008-03-02 07:28:16 +0100 (Sun, 02 Mar 2008) | 2 lines It's 2.6 now. ........ r61166 | georg.brandl | 2008-03-02 07:32:32 +0100 (Sun, 02 Mar 2008) | 2 lines Update year. ........ r61167 | georg.brandl | 2008-03-02 07:44:08 +0100 (Sun, 02 Mar 2008) | 2 lines Make patchlevel print out the release if called as a script. ........ r61168 | georg.brandl | 2008-03-02 07:45:40 +0100 (Sun, 02 Mar 2008) | 2 lines New default basename for HTML help files. ........ r61170 | raymond.hettinger | 2008-03-02 11:59:31 +0100 (Sun, 02 Mar 2008) | 1 line Finish-up docs for combinations() and permutations() in itertools. ........ r61171 | raymond.hettinger | 2008-03-02 12:17:51 +0100 (Sun, 02 Mar 2008) | 1 line Tighten example code. ........ r61172 | raymond.hettinger | 2008-03-02 12:57:16 +0100 (Sun, 02 Mar 2008) | 1 line Simplify code for itertools.product(). ........ r61173 | raymond.hettinger | 2008-03-02 13:02:19 +0100 (Sun, 02 Mar 2008) | 1 line Handle 0-tuples which can be singletons. ........ r61176 | georg.brandl | 2008-03-02 14:41:39 +0100 (Sun, 02 Mar 2008) | 2 lines Make clear that the constants are strings. ........ r61177 | georg.brandl | 2008-03-02 15:15:04 +0100 (Sun, 02 Mar 2008) | 2 lines Fix factual error. ........ r61183 | gregory.p.smith | 2008-03-02 21:00:53 +0100 (Sun, 02 Mar 2008) | 4 lines Modify import of test_support so that the code can also be used with a stand alone distribution of bsddb that includes its own small copy of test_support for the needed functionality on older pythons. ........
2008-03-02 18:46:37 -04:00
yield tuple(pool[i] for i in indices[:r])
while n:
for i in reversed(range(r)):
cycles[i] -= 1
if cycles[i] == 0:
indices[i:] = indices[i+1:] + indices[i:i+1]
cycles[i] = n - i
else:
j = cycles[i]
indices[i], indices[-j] = indices[-j], indices[i]
yield tuple(pool[i] for i in indices[:r])
break
else:
return
The code for :func:`permutations` can be also expressed as a subsequence of
:func:`product`, filtered to exclude entries with repeated elements (those
from the same position in the input pool)::
Merged revisions 61209-61214,61217-61222,61224-61226,61233-61237 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61209 | georg.brandl | 2008-03-03 21:37:55 +0100 (Mon, 03 Mar 2008) | 2 lines There are now sixteen isfoo functions. ........ r61210 | georg.brandl | 2008-03-03 21:39:00 +0100 (Mon, 03 Mar 2008) | 2 lines 15 -> 16, the 2nd ........ r61211 | georg.brandl | 2008-03-03 22:22:47 +0100 (Mon, 03 Mar 2008) | 2 lines Actually import itertools. ........ r61212 | georg.brandl | 2008-03-03 22:31:50 +0100 (Mon, 03 Mar 2008) | 2 lines Expand a bit on genexp scopes. ........ r61213 | raymond.hettinger | 2008-03-03 23:04:55 +0100 (Mon, 03 Mar 2008) | 1 line Remove dependency on itertools -- a simple genexp suffices. ........ r61214 | raymond.hettinger | 2008-03-03 23:19:58 +0100 (Mon, 03 Mar 2008) | 1 line Issue 2226: Callable checked for the wrong abstract method. ........ r61217 | andrew.kuchling | 2008-03-04 01:40:32 +0100 (Tue, 04 Mar 2008) | 1 line Typo fix ........ r61218 | andrew.kuchling | 2008-03-04 02:30:10 +0100 (Tue, 04 Mar 2008) | 1 line Grammar fix; markup fix ........ r61219 | andrew.kuchling | 2008-03-04 02:47:38 +0100 (Tue, 04 Mar 2008) | 1 line Fix sentence fragment ........ r61220 | andrew.kuchling | 2008-03-04 02:48:26 +0100 (Tue, 04 Mar 2008) | 1 line Typo fix ........ r61221 | andrew.kuchling | 2008-03-04 02:49:37 +0100 (Tue, 04 Mar 2008) | 1 line Add versionadded tags ........ r61222 | andrew.kuchling | 2008-03-04 02:50:32 +0100 (Tue, 04 Mar 2008) | 1 line Thesis night results: add various items ........ r61224 | raymond.hettinger | 2008-03-04 05:17:08 +0100 (Tue, 04 Mar 2008) | 1 line Beef-up docs and tests for itertools. Fix-up end-case for product(). ........ r61225 | georg.brandl | 2008-03-04 08:25:54 +0100 (Tue, 04 Mar 2008) | 2 lines Fix some patch attributions. ........ r61226 | georg.brandl | 2008-03-04 08:33:30 +0100 (Tue, 04 Mar 2008) | 2 lines #2230: document that PyArg_* leaves addresses alone on error. ........ r61233 | neal.norwitz | 2008-03-04 17:22:46 +0100 (Tue, 04 Mar 2008) | 3 lines Close the file before trying to remove the directory so it works on Windows. As reported by Trent Nelson on python-dev. ........ r61234 | thomas.heller | 2008-03-04 21:09:11 +0100 (Tue, 04 Mar 2008) | 9 lines Merged changes from libffi3-branch. The bundled libffi copy is now in sync with the recently released libffi3.0.4 version, apart from some small changes to Modules/_ctypes/libffi/configure.ac. I gave up on using libffi3 files on os x. Instead, static configuration with files from pyobjc is used. ........ r61235 | thomas.heller | 2008-03-04 21:21:42 +0100 (Tue, 04 Mar 2008) | 1 line Try to fix the build for PY_LINUX. ........ r61236 | fred.drake | 2008-03-04 22:14:04 +0100 (Tue, 04 Mar 2008) | 2 lines fix typo ........ r61237 | raymond.hettinger | 2008-03-04 23:29:44 +0100 (Tue, 04 Mar 2008) | 1 line Fix refleak in chain(). ........
2008-03-04 19:39:23 -04:00
def permutations(iterable, r=None):
pool = tuple(iterable)
n = len(pool)
r = n if r is None else r
for indices in product(range(n), repeat=r):
if len(set(indices)) == r:
yield tuple(pool[i] for i in indices)
The number of items returned is ``n! / (n-r)!`` when ``0 <= r <= n``
or zero when ``r > n``.
.. function:: product(*iterables, repeat=1)
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60751,60753,60756-60757,60759-60761,60763-60764,60766,60769-60770,60774-60784,60787-60789,60793,60796,60799-60809,60812-60813,60815-60821,60823-60826,60828-60829,60831-60834,60836,60838-60839,60846-60849,60852-60854,60856-60859,60861-60870,60874-60875,60880-60881,60886,60888-60890,60892,60894-60898,60900,60902-60906,60908,60911-60917,60919-60920,60922,60926,60929-60931,60933-60935,60937,60939-60941,60943-60954,60959-60961,60963-60969,60971-60976 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60965 | eric.smith | 2008-02-22 18:43:17 +0100 (Fri, 22 Feb 2008) | 1 line Tests for bin() builtin. These need to get merged into py3k, which has no tests for bin. ........ r60968 | raymond.hettinger | 2008-02-22 20:50:06 +0100 (Fri, 22 Feb 2008) | 1 line Document itertools.product(). ........ r60969 | raymond.hettinger | 2008-02-23 03:20:41 +0100 (Sat, 23 Feb 2008) | 9 lines Improve the implementation of itertools.product() * Fix-up issues pointed-out by Neal Norwitz. * Add extensive comments. * The lz->result variable is now a tuple instead of a list. * Use fast macro getitem/setitem calls so most code is in-line. * Re-use the result tuple if available (modify in-place instead of copy). ........ r60972 | raymond.hettinger | 2008-02-23 05:03:50 +0100 (Sat, 23 Feb 2008) | 1 line Add more comments ........ r60973 | raymond.hettinger | 2008-02-23 11:04:15 +0100 (Sat, 23 Feb 2008) | 1 line Add recipe using itertools.product(). ........ r60974 | facundo.batista | 2008-02-23 13:01:13 +0100 (Sat, 23 Feb 2008) | 6 lines Issue 1881. Increased the stack limit from 500 to 1500. Also added a test for this (and because of this test you'll see in stderr a message that parser.c sends before raising MemoryError). Thanks Ralf Schmitt. ........ r60975 | facundo.batista | 2008-02-23 13:27:17 +0100 (Sat, 23 Feb 2008) | 4 lines Issue 1776581. Minor corrections to smtplib, and two small tests. Thanks Alan McIntyre. ........ r60976 | facundo.batista | 2008-02-23 13:46:10 +0100 (Sat, 23 Feb 2008) | 5 lines Issue 1781. Now ConfigParser.add_section does not let you add a DEFAULT section any more, because it duplicated sections with the rest of the machinery. Thanks Tim Lesher and Manuel Kaufmann. ........
2008-02-23 09:18:03 -04:00
Cartesian product of input iterables.
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60751,60753,60756-60757,60759-60761,60763-60764,60766,60769-60770,60774-60784,60787-60789,60793,60796,60799-60809,60812-60813,60815-60821,60823-60826,60828-60829,60831-60834,60836,60838-60839,60846-60849,60852-60854,60856-60859,60861-60870,60874-60875,60880-60881,60886,60888-60890,60892,60894-60898,60900,60902-60906,60908,60911-60917,60919-60920,60922,60926,60929-60931,60933-60935,60937,60939-60941,60943-60954,60959-60961,60963-60969,60971-60976 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60965 | eric.smith | 2008-02-22 18:43:17 +0100 (Fri, 22 Feb 2008) | 1 line Tests for bin() builtin. These need to get merged into py3k, which has no tests for bin. ........ r60968 | raymond.hettinger | 2008-02-22 20:50:06 +0100 (Fri, 22 Feb 2008) | 1 line Document itertools.product(). ........ r60969 | raymond.hettinger | 2008-02-23 03:20:41 +0100 (Sat, 23 Feb 2008) | 9 lines Improve the implementation of itertools.product() * Fix-up issues pointed-out by Neal Norwitz. * Add extensive comments. * The lz->result variable is now a tuple instead of a list. * Use fast macro getitem/setitem calls so most code is in-line. * Re-use the result tuple if available (modify in-place instead of copy). ........ r60972 | raymond.hettinger | 2008-02-23 05:03:50 +0100 (Sat, 23 Feb 2008) | 1 line Add more comments ........ r60973 | raymond.hettinger | 2008-02-23 11:04:15 +0100 (Sat, 23 Feb 2008) | 1 line Add recipe using itertools.product(). ........ r60974 | facundo.batista | 2008-02-23 13:01:13 +0100 (Sat, 23 Feb 2008) | 6 lines Issue 1881. Increased the stack limit from 500 to 1500. Also added a test for this (and because of this test you'll see in stderr a message that parser.c sends before raising MemoryError). Thanks Ralf Schmitt. ........ r60975 | facundo.batista | 2008-02-23 13:27:17 +0100 (Sat, 23 Feb 2008) | 4 lines Issue 1776581. Minor corrections to smtplib, and two small tests. Thanks Alan McIntyre. ........ r60976 | facundo.batista | 2008-02-23 13:46:10 +0100 (Sat, 23 Feb 2008) | 5 lines Issue 1781. Now ConfigParser.add_section does not let you add a DEFAULT section any more, because it duplicated sections with the rest of the machinery. Thanks Tim Lesher and Manuel Kaufmann. ........
2008-02-23 09:18:03 -04:00
Roughly equivalent to nested for-loops in a generator expression. For example,
``product(A, B)`` returns the same as ``((x,y) for x in A for y in B)``.
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60751,60753,60756-60757,60759-60761,60763-60764,60766,60769-60770,60774-60784,60787-60789,60793,60796,60799-60809,60812-60813,60815-60821,60823-60826,60828-60829,60831-60834,60836,60838-60839,60846-60849,60852-60854,60856-60859,60861-60870,60874-60875,60880-60881,60886,60888-60890,60892,60894-60898,60900,60902-60906,60908,60911-60917,60919-60920,60922,60926,60929-60931,60933-60935,60937,60939-60941,60943-60954,60959-60961,60963-60969,60971-60976 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60965 | eric.smith | 2008-02-22 18:43:17 +0100 (Fri, 22 Feb 2008) | 1 line Tests for bin() builtin. These need to get merged into py3k, which has no tests for bin. ........ r60968 | raymond.hettinger | 2008-02-22 20:50:06 +0100 (Fri, 22 Feb 2008) | 1 line Document itertools.product(). ........ r60969 | raymond.hettinger | 2008-02-23 03:20:41 +0100 (Sat, 23 Feb 2008) | 9 lines Improve the implementation of itertools.product() * Fix-up issues pointed-out by Neal Norwitz. * Add extensive comments. * The lz->result variable is now a tuple instead of a list. * Use fast macro getitem/setitem calls so most code is in-line. * Re-use the result tuple if available (modify in-place instead of copy). ........ r60972 | raymond.hettinger | 2008-02-23 05:03:50 +0100 (Sat, 23 Feb 2008) | 1 line Add more comments ........ r60973 | raymond.hettinger | 2008-02-23 11:04:15 +0100 (Sat, 23 Feb 2008) | 1 line Add recipe using itertools.product(). ........ r60974 | facundo.batista | 2008-02-23 13:01:13 +0100 (Sat, 23 Feb 2008) | 6 lines Issue 1881. Increased the stack limit from 500 to 1500. Also added a test for this (and because of this test you'll see in stderr a message that parser.c sends before raising MemoryError). Thanks Ralf Schmitt. ........ r60975 | facundo.batista | 2008-02-23 13:27:17 +0100 (Sat, 23 Feb 2008) | 4 lines Issue 1776581. Minor corrections to smtplib, and two small tests. Thanks Alan McIntyre. ........ r60976 | facundo.batista | 2008-02-23 13:46:10 +0100 (Sat, 23 Feb 2008) | 5 lines Issue 1781. Now ConfigParser.add_section does not let you add a DEFAULT section any more, because it duplicated sections with the rest of the machinery. Thanks Tim Lesher and Manuel Kaufmann. ........
2008-02-23 09:18:03 -04:00
The nested loops cycle like an odometer with the rightmost element advancing
on every iteration. This pattern creates a lexicographic ordering so that if
the input's iterables are sorted, the product tuples are emitted in sorted
order.
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60751,60753,60756-60757,60759-60761,60763-60764,60766,60769-60770,60774-60784,60787-60789,60793,60796,60799-60809,60812-60813,60815-60821,60823-60826,60828-60829,60831-60834,60836,60838-60839,60846-60849,60852-60854,60856-60859,60861-60870,60874-60875,60880-60881,60886,60888-60890,60892,60894-60898,60900,60902-60906,60908,60911-60917,60919-60920,60922,60926,60929-60931,60933-60935,60937,60939-60941,60943-60954,60959-60961,60963-60969,60971-60976 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60965 | eric.smith | 2008-02-22 18:43:17 +0100 (Fri, 22 Feb 2008) | 1 line Tests for bin() builtin. These need to get merged into py3k, which has no tests for bin. ........ r60968 | raymond.hettinger | 2008-02-22 20:50:06 +0100 (Fri, 22 Feb 2008) | 1 line Document itertools.product(). ........ r60969 | raymond.hettinger | 2008-02-23 03:20:41 +0100 (Sat, 23 Feb 2008) | 9 lines Improve the implementation of itertools.product() * Fix-up issues pointed-out by Neal Norwitz. * Add extensive comments. * The lz->result variable is now a tuple instead of a list. * Use fast macro getitem/setitem calls so most code is in-line. * Re-use the result tuple if available (modify in-place instead of copy). ........ r60972 | raymond.hettinger | 2008-02-23 05:03:50 +0100 (Sat, 23 Feb 2008) | 1 line Add more comments ........ r60973 | raymond.hettinger | 2008-02-23 11:04:15 +0100 (Sat, 23 Feb 2008) | 1 line Add recipe using itertools.product(). ........ r60974 | facundo.batista | 2008-02-23 13:01:13 +0100 (Sat, 23 Feb 2008) | 6 lines Issue 1881. Increased the stack limit from 500 to 1500. Also added a test for this (and because of this test you'll see in stderr a message that parser.c sends before raising MemoryError). Thanks Ralf Schmitt. ........ r60975 | facundo.batista | 2008-02-23 13:27:17 +0100 (Sat, 23 Feb 2008) | 4 lines Issue 1776581. Minor corrections to smtplib, and two small tests. Thanks Alan McIntyre. ........ r60976 | facundo.batista | 2008-02-23 13:46:10 +0100 (Sat, 23 Feb 2008) | 5 lines Issue 1781. Now ConfigParser.add_section does not let you add a DEFAULT section any more, because it duplicated sections with the rest of the machinery. Thanks Tim Lesher and Manuel Kaufmann. ........
2008-02-23 09:18:03 -04:00
To compute the product of an iterable with itself, specify the number of
repetitions with the optional *repeat* keyword argument. For example,
``product(A, repeat=4)`` means the same as ``product(A, A, A, A)``.
Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61062,61066,61068,61070,61083,61085,61092-61103 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r61098 | jeffrey.yasskin | 2008-02-28 05:45:36 +0100 (Thu, 28 Feb 2008) | 7 lines Move abc._Abstract into object by adding a new flag Py_TPFLAGS_IS_ABSTRACT, which forbids constructing types that have it set. The effect is to speed ./python.exe -m timeit -s 'import abc' -s 'class Foo(object): __metaclass__ = abc.ABCMeta' 'Foo()' up from 2.5us to 0.201us. This fixes issue 1762. ........ r61099 | jeffrey.yasskin | 2008-02-28 06:53:18 +0100 (Thu, 28 Feb 2008) | 3 lines Speed test_socketserver up from 28.739s to 0.226s, simplify the logic, and make sure all tests run even if some fail. ........ r61100 | jeffrey.yasskin | 2008-02-28 07:09:19 +0100 (Thu, 28 Feb 2008) | 21 lines Thread.start() used sleep(0.000001) to make sure it didn't return before the new thread had started. At least on my MacBook Pro, that wound up sleeping for a full 10ms (probably 1 jiffy). By using an Event instead, we can be absolutely certain that the thread has started, and return more quickly (217us). Before: $ ./python.exe -m timeit -s 'from threading import Thread' 't = Thread(); t.start(); t.join()' 100 loops, best of 3: 10.3 msec per loop $ ./python.exe -m timeit -s 'from threading import Thread; t = Thread()' 't.isAlive()' 1000000 loops, best of 3: 0.47 usec per loop After: $ ./python.exe -m timeit -s 'from threading import Thread' 't = Thread(); t.start(); t.join()' 1000 loops, best of 3: 217 usec per loop $ ./python.exe -m timeit -s 'from threading import Thread; t = Thread()' 't.isAlive()' 1000000 loops, best of 3: 0.86 usec per loop To be fair, the 10ms isn't CPU time, and other threads including the spawned one get to run during it. There are also some slightly more complicated ways to get back the .4us in isAlive() if we want. ........ r61101 | raymond.hettinger | 2008-02-28 10:23:48 +0100 (Thu, 28 Feb 2008) | 1 line Add repeat keyword argument to itertools.product(). ........ r61102 | christian.heimes | 2008-02-28 12:18:49 +0100 (Thu, 28 Feb 2008) | 1 line The empty tuple is usually a singleton with a much higher refcnt than 1 ........
2008-02-28 08:27:11 -04:00
This function is roughly equivalent to the following code, except that the
actual implementation does not build up intermediate results in memory::
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def product(*args, repeat=1):
# product('ABCD', 'xy') --> Ax Ay Bx By Cx Cy Dx Dy
# product(range(2), repeat=3) --> 000 001 010 011 100 101 110 111
pools = [tuple(pool) for pool in args] * repeat
result = [[]]
for pool in pools:
result = [x+[y] for x in result for y in pool]
for prod in result:
yield tuple(prod)
Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60751,60753,60756-60757,60759-60761,60763-60764,60766,60769-60770,60774-60784,60787-60789,60793,60796,60799-60809,60812-60813,60815-60821,60823-60826,60828-60829,60831-60834,60836,60838-60839,60846-60849,60852-60854,60856-60859,60861-60870,60874-60875,60880-60881,60886,60888-60890,60892,60894-60898,60900,60902-60906,60908,60911-60917,60919-60920,60922,60926,60929-60931,60933-60935,60937,60939-60941,60943-60954,60959-60961,60963-60969,60971-60976 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r60965 | eric.smith | 2008-02-22 18:43:17 +0100 (Fri, 22 Feb 2008) | 1 line Tests for bin() builtin. These need to get merged into py3k, which has no tests for bin. ........ r60968 | raymond.hettinger | 2008-02-22 20:50:06 +0100 (Fri, 22 Feb 2008) | 1 line Document itertools.product(). ........ r60969 | raymond.hettinger | 2008-02-23 03:20:41 +0100 (Sat, 23 Feb 2008) | 9 lines Improve the implementation of itertools.product() * Fix-up issues pointed-out by Neal Norwitz. * Add extensive comments. * The lz->result variable is now a tuple instead of a list. * Use fast macro getitem/setitem calls so most code is in-line. * Re-use the result tuple if available (modify in-place instead of copy). ........ r60972 | raymond.hettinger | 2008-02-23 05:03:50 +0100 (Sat, 23 Feb 2008) | 1 line Add more comments ........ r60973 | raymond.hettinger | 2008-02-23 11:04:15 +0100 (Sat, 23 Feb 2008) | 1 line Add recipe using itertools.product(). ........ r60974 | facundo.batista | 2008-02-23 13:01:13 +0100 (Sat, 23 Feb 2008) | 6 lines Issue 1881. Increased the stack limit from 500 to 1500. Also added a test for this (and because of this test you'll see in stderr a message that parser.c sends before raising MemoryError). Thanks Ralf Schmitt. ........ r60975 | facundo.batista | 2008-02-23 13:27:17 +0100 (Sat, 23 Feb 2008) | 4 lines Issue 1776581. Minor corrections to smtplib, and two small tests. Thanks Alan McIntyre. ........ r60976 | facundo.batista | 2008-02-23 13:46:10 +0100 (Sat, 23 Feb 2008) | 5 lines Issue 1781. Now ConfigParser.add_section does not let you add a DEFAULT section any more, because it duplicated sections with the rest of the machinery. Thanks Tim Lesher and Manuel Kaufmann. ........
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.. function:: repeat(object[, times])
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Make an iterator that returns *object* over and over again. Runs indefinitely
unless the *times* argument is specified. Used as argument to :func:`map` for
invariant parameters to the called function. Also used with :func:`zip` to
create an invariant part of a tuple record.
Roughly equivalent to::
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def repeat(object, times=None):
# repeat(10, 3) --> 10 10 10
if times is None:
while True:
yield object
else:
for i in range(times):
yield object
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A common use for *repeat* is to supply a stream of constant values to *map*
or *zip*::
>>> list(map(pow, range(10), repeat(2)))
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
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.. function:: starmap(function, iterable)
Make an iterator that computes the function using arguments obtained from
the iterable. Used instead of :func:`map` when argument parameters are already
grouped in tuples from a single iterable (the data has been "pre-zipped"). The
difference between :func:`map` and :func:`starmap` parallels the distinction
between ``function(a,b)`` and ``function(*c)``. Roughly equivalent to::
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def starmap(function, iterable):
# starmap(pow, [(2,5), (3,2), (10,3)]) --> 32 9 1000
for args in iterable:
yield function(*args)
Merged revisions 59985-60000,60002,60005-60007,60009-60042 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59987 | raymond.hettinger | 2008-01-15 21:52:42 +0100 (Tue, 15 Jan 2008) | 1 line Refactor if/elif chain for clarity and speed. Remove dependency on subclasses having to implement _empty and _full. ........ r59988 | raymond.hettinger | 2008-01-15 22:22:47 +0100 (Tue, 15 Jan 2008) | 1 line Fix-up half-written paragraph in the docs ........ r59989 | amaury.forgeotdarc | 2008-01-15 22:25:11 +0100 (Tue, 15 Jan 2008) | 3 lines test_doctest fails since r59984. Not sure if these are the correct values, but save_stdout has to be set before its usage... ........ r59992 | andrew.kuchling | 2008-01-16 01:32:03 +0100 (Wed, 16 Jan 2008) | 1 line Docstring typos ........ r59993 | andrew.kuchling | 2008-01-16 04:17:25 +0100 (Wed, 16 Jan 2008) | 1 line Add PEP 3141 section ........ r59998 | andrew.kuchling | 2008-01-16 14:01:51 +0100 (Wed, 16 Jan 2008) | 1 line Markup fix ........ r59999 | georg.brandl | 2008-01-16 17:56:29 +0100 (Wed, 16 Jan 2008) | 2 lines Fix MSDN library URL. (#1854) ........ r60006 | georg.brandl | 2008-01-16 21:27:56 +0100 (Wed, 16 Jan 2008) | 3 lines Add Python-specific content to Doc dir. Update configuration file to work with the newest Sphinx. ........ r60007 | georg.brandl | 2008-01-16 21:29:00 +0100 (Wed, 16 Jan 2008) | 2 lines Doc build should work with 2.4 now. ........ r60009 | raymond.hettinger | 2008-01-17 00:38:16 +0100 (Thu, 17 Jan 2008) | 1 line Minor wordsmithing. ........ r60010 | raymond.hettinger | 2008-01-17 00:40:45 +0100 (Thu, 17 Jan 2008) | 1 line Add queues will alternative fetch orders (priority based and stack based). ........ r60011 | raymond.hettinger | 2008-01-17 00:49:35 +0100 (Thu, 17 Jan 2008) | 1 line Add news entry. ........ r60013 | raymond.hettinger | 2008-01-17 04:02:14 +0100 (Thu, 17 Jan 2008) | 1 line Make starmap() match its pure python definition and accept any itertable input (not just tuples). ........ r60015 | gregory.p.smith | 2008-01-17 08:43:20 +0100 (Thu, 17 Jan 2008) | 3 lines Comply with RFC 3207. Fixes issue 829951 - http://bugs.python.org/issue829951 ........ r60018 | gregory.p.smith | 2008-01-17 09:03:17 +0100 (Thu, 17 Jan 2008) | 2 lines entry for r60015 ........ r60019 | raymond.hettinger | 2008-01-17 09:07:05 +0100 (Thu, 17 Jan 2008) | 1 line Note versionadded. ........ r60020 | gregory.p.smith | 2008-01-17 09:35:49 +0100 (Thu, 17 Jan 2008) | 8 lines Fixes (accepts patch) issue1339 - http://bugs.python.org/issue1339 - Factor out the duplication of EHLO/HELO in login() and sendmail() to a new function, ehlo_or_helo_if_needed(). - Use ehlo_or_helo_if_needed() in starttls() - Check for the starttls exception in starttls() in the same way as login() checks for the auth extension. Contributed by Bill Fenner. ........ r60021 | andrew.kuchling | 2008-01-17 13:00:15 +0100 (Thu, 17 Jan 2008) | 1 line Revise 3141 section a bit; add some Windows items ........ r60022 | brett.cannon | 2008-01-17 19:45:10 +0100 (Thu, 17 Jan 2008) | 2 lines Fix a function pointer declaration to silence the compiler. ........ r60024 | raymond.hettinger | 2008-01-17 20:31:38 +0100 (Thu, 17 Jan 2008) | 1 line Issue #1861: Add read-only attribute listing upcoming events in the order they will be run. ........ r60025 | andrew.kuchling | 2008-01-17 20:49:24 +0100 (Thu, 17 Jan 2008) | 1 line Correction from Jordan Lewis: halfdelay() uses tenths of a second, not milliseconds ........ r60026 | raymond.hettinger | 2008-01-17 23:27:49 +0100 (Thu, 17 Jan 2008) | 1 line Add advice on choosing between scheduler and threading.Timer(). ........ r60028 | christian.heimes | 2008-01-18 00:01:44 +0100 (Fri, 18 Jan 2008) | 2 lines Updated new property syntax. An elaborate example for subclassing and the getter was missing. Added comment about VS 2008 and PGO builds. ........ r60029 | raymond.hettinger | 2008-01-18 00:32:01 +0100 (Fri, 18 Jan 2008) | 1 line Fix-up Timer() example. ........ r60030 | raymond.hettinger | 2008-01-18 00:56:56 +0100 (Fri, 18 Jan 2008) | 1 line Fix markup ........ r60031 | raymond.hettinger | 2008-01-18 01:10:42 +0100 (Fri, 18 Jan 2008) | 1 line clearcache() needs to remove the dict as well as clear it. ........ r60033 | andrew.kuchling | 2008-01-18 03:26:16 +0100 (Fri, 18 Jan 2008) | 1 line Bump verson ........ r60034 | andrew.kuchling | 2008-01-18 03:42:52 +0100 (Fri, 18 Jan 2008) | 1 line Typo fix ........ r60035 | christian.heimes | 2008-01-18 08:30:20 +0100 (Fri, 18 Jan 2008) | 3 lines Coverity issue CID #197 var_decl: Declared variable "stm" without initializer ninit_use_in_call: Using uninitialized value "stm" (field "stm".tm_zone uninitialized) in call to function "mktime" ........ r60036 | christian.heimes | 2008-01-18 08:45:30 +0100 (Fri, 18 Jan 2008) | 11 lines Coverity issue CID #167 Event alloc_fn: Called allocation function "metacompile" [model] Event var_assign: Assigned variable "gr" to storage returned from "metacompile" gr = metacompile(n); Event pass_arg: Variable "gr" not freed or pointed-to in function "maketables" [model] g = maketables(gr); translatelabels(g); addfirstsets(g); Event leaked_storage: Returned without freeing storage "gr" return g; ........ r60038 | christian.heimes | 2008-01-18 09:04:57 +0100 (Fri, 18 Jan 2008) | 3 lines Coverity issue CID #182 size_error: Allocating 1 bytes to pointer "children", which needs at least 4 bytes ........ r60041 | christian.heimes | 2008-01-18 09:47:59 +0100 (Fri, 18 Jan 2008) | 4 lines Coverity issue CID #169 local_ptr_assign_local: Assigning address of stack variable "namebuf" to pointer "filename" out_of_scope: Variable "namebuf" goes out of scope use_invalid: Used "filename" pointing to out-of-scope variable "namebuf" ........ r60042 | christian.heimes | 2008-01-18 09:53:45 +0100 (Fri, 18 Jan 2008) | 2 lines Coverity CID #168 leaked_storage: Returned without freeing storage "fp" ........
2008-01-18 05:56:22 -04:00
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.. function:: takewhile(predicate, iterable)
Make an iterator that returns elements from the iterable as long as the
predicate is true. Roughly equivalent to::
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def takewhile(predicate, iterable):
# takewhile(lambda x: x<5, [1,4,6,4,1]) --> 1 4
for x in iterable:
if predicate(x):
yield x
else:
break
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.. function:: tee(iterable, n=2)
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Return *n* independent iterators from a single iterable.
The following Python code helps explain what *tee* does (although the actual
2016-05-16 03:31:54 -03:00
implementation is more complex and uses only a single underlying
:abbr:`FIFO (first-in, first-out)` queue).
Roughly equivalent to::
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def tee(iterable, n=2):
it = iter(iterable)
deques = [collections.deque() for i in range(n)]
def gen(mydeque):
while True:
if not mydeque: # when the local deque is empty
try:
newval = next(it) # fetch a new value and
except StopIteration:
return
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for d in deques: # load it to all the deques
d.append(newval)
yield mydeque.popleft()
return tuple(gen(d) for d in deques)
Once :func:`tee` has made a split, the original *iterable* should not be
used anywhere else; otherwise, the *iterable* could get advanced without
the tee objects being informed.
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This itertool may require significant auxiliary storage (depending on how
much temporary data needs to be stored). In general, if one iterator uses
most or all of the data before another iterator starts, it is faster to use
:func:`list` instead of :func:`tee`.
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.. function:: zip_longest(*iterables, fillvalue=None)
Make an iterator that aggregates elements from each of the iterables. If the
iterables are of uneven length, missing values are filled-in with *fillvalue*.
Iteration continues until the longest iterable is exhausted. Roughly equivalent to::
class ZipExhausted(Exception):
pass
def zip_longest(*args, **kwds):
# zip_longest('ABCD', 'xy', fillvalue='-') --> Ax By C- D-
fillvalue = kwds.get('fillvalue')
counter = len(args) - 1
def sentinel():
nonlocal counter
if not counter:
raise ZipExhausted
counter -= 1
yield fillvalue
fillers = repeat(fillvalue)
iterators = [chain(it, sentinel(), fillers) for it in args]
try:
while iterators:
yield tuple(map(next, iterators))
except ZipExhausted:
pass
If one of the iterables is potentially infinite, then the :func:`zip_longest`
function should be wrapped with something that limits the number of calls
(for example :func:`islice` or :func:`takewhile`). If not specified,
*fillvalue* defaults to ``None``.
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.. _itertools-recipes:
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Itertools Recipes
-----------------
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This section shows recipes for creating an extended toolset using the existing
itertools as building blocks.
The extended tools offer the same high performance as the underlying toolset.
The superior memory performance is kept by processing elements one at a time
rather than bringing the whole iterable into memory all at once. Code volume is
kept small by linking the tools together in a functional style which helps
eliminate temporary variables. High speed is retained by preferring
#1370: Finish the merge r58749, log below, by resolving all conflicts in Doc/. Merged revisions 58221-58741 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r58221 | georg.brandl | 2007-09-20 10:57:59 -0700 (Thu, 20 Sep 2007) | 2 lines Patch #1181: add os.environ.clear() method. ........ r58225 | sean.reifschneider | 2007-09-20 23:33:28 -0700 (Thu, 20 Sep 2007) | 3 lines Issue1704287: "make install" fails unless you do "make" first. Make oldsharedmods and sharedmods in "libinstall". ........ r58232 | guido.van.rossum | 2007-09-22 13:18:03 -0700 (Sat, 22 Sep 2007) | 4 lines Patch # 188 by Philip Jenvey. Make tell() mark CRLF as a newline. With unit test. ........ r58242 | georg.brandl | 2007-09-24 10:55:47 -0700 (Mon, 24 Sep 2007) | 2 lines Fix typo and double word. ........ r58245 | georg.brandl | 2007-09-24 10:59:28 -0700 (Mon, 24 Sep 2007) | 2 lines #1196: document default radix for int(). ........ r58247 | georg.brandl | 2007-09-24 11:08:24 -0700 (Mon, 24 Sep 2007) | 2 lines #1177: accept 2xx responses for https too, not only http. ........ r58249 | andrew.kuchling | 2007-09-24 16:45:51 -0700 (Mon, 24 Sep 2007) | 1 line Remove stray odd character; grammar fix ........ r58250 | andrew.kuchling | 2007-09-24 16:46:28 -0700 (Mon, 24 Sep 2007) | 1 line Typo fix ........ r58251 | andrew.kuchling | 2007-09-24 17:09:42 -0700 (Mon, 24 Sep 2007) | 1 line Add various items ........ r58268 | vinay.sajip | 2007-09-26 22:34:45 -0700 (Wed, 26 Sep 2007) | 1 line Change to flush and close logic to fix #1760556. ........ r58269 | vinay.sajip | 2007-09-26 22:38:51 -0700 (Wed, 26 Sep 2007) | 1 line Change to basicConfig() to fix #1021. ........ r58270 | georg.brandl | 2007-09-26 23:26:58 -0700 (Wed, 26 Sep 2007) | 2 lines #1208: document match object's boolean value. ........ r58271 | vinay.sajip | 2007-09-26 23:56:13 -0700 (Wed, 26 Sep 2007) | 1 line Minor date change. ........ r58272 | vinay.sajip | 2007-09-27 00:35:10 -0700 (Thu, 27 Sep 2007) | 1 line Change to LogRecord.__init__() to fix #1206. Note that archaic use of type(x) == types.DictType is because of keeping 1.5.2 compatibility. While this is much less relevant these days, there probably needs to be a separate commit for removing all archaic constructs at the same time. ........ r58288 | brett.cannon | 2007-09-30 12:45:10 -0700 (Sun, 30 Sep 2007) | 9 lines tuple.__repr__ did not consider a reference loop as it is not possible from Python code; but it is possible from C. object.__str__ had the issue of not expecting a type to doing something within it's tp_str implementation that could trigger an infinite recursion, but it could in C code.. Both found thanks to BaseException and how it handles its repr. Closes issue #1686386. Thanks to Thomas Herve for taking an initial stab at coming up with a solution. ........ r58289 | brett.cannon | 2007-09-30 13:37:19 -0700 (Sun, 30 Sep 2007) | 3 lines Fix error introduced by r58288; if a tuple is length 0 return its repr and don't worry about any self-referring tuples. ........ r58294 | facundo.batista | 2007-10-02 10:01:24 -0700 (Tue, 02 Oct 2007) | 11 lines Made the various is_* operations return booleans. This was discussed with Cawlishaw by mail, and he basically confirmed that to these is_* operations, there's no need to return Decimal(0) and Decimal(1) if the language supports the False and True booleans. Also added a few tests for the these functions in extra.decTest, since they are mostly untested (apart from the doctests). Thanks Mark Dickinson ........ r58295 | facundo.batista | 2007-10-02 11:21:18 -0700 (Tue, 02 Oct 2007) | 4 lines Added a class to store the digits of log(10), so that they can be made available when necessary without recomputing. Thanks Mark Dickinson ........ r58299 | mark.summerfield | 2007-10-03 01:53:21 -0700 (Wed, 03 Oct 2007) | 4 lines Added note in footnote about string comparisons about unicodedata.normalize(). ........ r58304 | raymond.hettinger | 2007-10-03 14:18:11 -0700 (Wed, 03 Oct 2007) | 1 line enumerate() is no longer bounded to using sequences shorter than LONG_MAX. The possibility of overflow was sending some newsgroup posters into a tizzy. ........ r58305 | raymond.hettinger | 2007-10-03 17:20:27 -0700 (Wed, 03 Oct 2007) | 1 line itertools.count() no longer limited to sys.maxint. ........ r58306 | kurt.kaiser | 2007-10-03 18:49:54 -0700 (Wed, 03 Oct 2007) | 3 lines Assume that the user knows when he wants to end the line; don't insert something he didn't select or complete. ........ r58307 | kurt.kaiser | 2007-10-03 19:07:50 -0700 (Wed, 03 Oct 2007) | 2 lines Remove unused theme that was causing a fault in p3k. ........ r58308 | kurt.kaiser | 2007-10-03 19:09:17 -0700 (Wed, 03 Oct 2007) | 2 lines Clean up EditorWindow close. ........ r58309 | kurt.kaiser | 2007-10-03 19:53:07 -0700 (Wed, 03 Oct 2007) | 7 lines textView cleanup. Patch 1718043 Tal Einat. M idlelib/EditorWindow.py M idlelib/aboutDialog.py M idlelib/textView.py M idlelib/NEWS.txt ........ r58310 | kurt.kaiser | 2007-10-03 20:11:12 -0700 (Wed, 03 Oct 2007) | 3 lines configDialog cleanup. Patch 1730217 Tal Einat. ........ r58311 | neal.norwitz | 2007-10-03 23:00:48 -0700 (Wed, 03 Oct 2007) | 4 lines Coverity #151: Remove deadcode. All this code already exists above starting at line 653. ........ r58325 | fred.drake | 2007-10-04 19:46:12 -0700 (Thu, 04 Oct 2007) | 1 line wrap lines to <80 characters before fixing errors ........ r58326 | raymond.hettinger | 2007-10-04 19:47:07 -0700 (Thu, 04 Oct 2007) | 6 lines Add __asdict__() to NamedTuple and refine the docs. Add maxlen support to deque() and fixup docs. Partially fix __reduce__(). The None as a third arg was no longer supported. Still needs work on __reduce__() to handle recursive inputs. ........ r58327 | fred.drake | 2007-10-04 19:48:32 -0700 (Thu, 04 Oct 2007) | 3 lines move descriptions of ac_(in|out)_buffer_size to the right place http://bugs.python.org/issue1053 ........ r58329 | neal.norwitz | 2007-10-04 20:39:17 -0700 (Thu, 04 Oct 2007) | 3 lines dict could be NULL, so we need to XDECREF. Fix a compiler warning about passing a PyTypeObject* instead of PyObject*. ........ r58330 | neal.norwitz | 2007-10-04 20:41:19 -0700 (Thu, 04 Oct 2007) | 2 lines Fix Coverity #158: Check the correct variable. ........ r58332 | neal.norwitz | 2007-10-04 22:01:38 -0700 (Thu, 04 Oct 2007) | 7 lines Fix Coverity #159. This code was broken if save() returned a negative number since i contained a boolean value and then we compared i < 0 which should never be true. Will backport (assuming it's necessary) ........ r58334 | neal.norwitz | 2007-10-04 22:29:17 -0700 (Thu, 04 Oct 2007) | 1 line Add a note about fixing some more warnings found by Coverity. ........ r58338 | raymond.hettinger | 2007-10-05 12:07:31 -0700 (Fri, 05 Oct 2007) | 1 line Restore BEGIN/END THREADS macros which were squashed in the previous checkin ........ r58343 | gregory.p.smith | 2007-10-06 00:48:10 -0700 (Sat, 06 Oct 2007) | 3 lines Stab in the dark attempt to fix the test_bsddb3 failure on sparc and S-390 ubuntu buildbots. ........ r58344 | gregory.p.smith | 2007-10-06 00:51:59 -0700 (Sat, 06 Oct 2007) | 2 lines Allows BerkeleyDB 4.6.x >= 4.6.21 for the bsddb module. ........ r58348 | gregory.p.smith | 2007-10-06 08:47:37 -0700 (Sat, 06 Oct 2007) | 3 lines Use the host the author likely meant in the first place. pop.gmail.com is reliable. gmail.org is someones personal domain. ........ r58351 | neal.norwitz | 2007-10-06 12:16:28 -0700 (Sat, 06 Oct 2007) | 3 lines Ensure that this test will pass even if another test left an unwritable TESTFN. Also use the safe unlink in test_support instead of rolling our own here. ........ r58368 | georg.brandl | 2007-10-08 00:50:24 -0700 (Mon, 08 Oct 2007) | 3 lines #1123: fix the docs for the str.split(None, sep) case. Also expand a few other methods' docs, which had more info in the deprecated string module docs. ........ r58369 | georg.brandl | 2007-10-08 01:06:05 -0700 (Mon, 08 Oct 2007) | 2 lines Update docstring of sched, also remove an unused assignment. ........ r58370 | raymond.hettinger | 2007-10-08 02:14:28 -0700 (Mon, 08 Oct 2007) | 5 lines Add comments to NamedTuple code. Let the field spec be either a string or a non-string sequence (suggested by Martin Blais with use cases). Improve the error message in the case of a SyntaxError (caused by a duplicate field name). ........ r58371 | raymond.hettinger | 2007-10-08 02:56:29 -0700 (Mon, 08 Oct 2007) | 1 line Missed a line in the docs ........ r58372 | raymond.hettinger | 2007-10-08 03:11:51 -0700 (Mon, 08 Oct 2007) | 1 line Better variable names ........ r58376 | georg.brandl | 2007-10-08 07:12:47 -0700 (Mon, 08 Oct 2007) | 3 lines #1199: docs for tp_as_{number,sequence,mapping}, by Amaury Forgeot d'Arc. No need to merge this to py3k! ........ r58380 | raymond.hettinger | 2007-10-08 14:26:58 -0700 (Mon, 08 Oct 2007) | 1 line Eliminate camelcase function name ........ r58381 | andrew.kuchling | 2007-10-08 16:23:03 -0700 (Mon, 08 Oct 2007) | 1 line Eliminate camelcase function name ........ r58382 | raymond.hettinger | 2007-10-08 18:36:23 -0700 (Mon, 08 Oct 2007) | 1 line Make the error messages more specific ........ r58384 | gregory.p.smith | 2007-10-08 23:02:21 -0700 (Mon, 08 Oct 2007) | 10 lines Splits Modules/_bsddb.c up into bsddb.h and _bsddb.c and adds a C API object available as bsddb.db.api. This is based on the patch submitted by Duncan Grisby here: http://sourceforge.net/tracker/index.php?func=detail&aid=1551895&group_id=13900&atid=313900 See this thread for additional info: http://sourceforge.net/mailarchive/forum.php?thread_name=E1GAVDK-0002rk-Iw%40apasphere.com&forum_name=pybsddb-users It also cleans up the code a little by removing some ifdef/endifs for python prior to 2.1 and for unsupported Berkeley DB <= 3.2. ........ r58385 | gregory.p.smith | 2007-10-08 23:50:43 -0700 (Mon, 08 Oct 2007) | 5 lines Fix a double free when positioning a database cursor to a non-existant string key (and probably a few other situations with string keys). This was reported with a patch as pybsddb sourceforge bug 1708868 by jjjhhhlll at gmail. ........ r58386 | gregory.p.smith | 2007-10-09 00:19:11 -0700 (Tue, 09 Oct 2007) | 3 lines Use the highest cPickle protocol in bsddb.dbshelve. This comes from sourceforge pybsddb patch 1551443 by w_barnes. ........ r58394 | gregory.p.smith | 2007-10-09 11:26:02 -0700 (Tue, 09 Oct 2007) | 2 lines remove another sleepycat reference ........ r58396 | kurt.kaiser | 2007-10-09 12:31:30 -0700 (Tue, 09 Oct 2007) | 3 lines Allow interrupt only when executing user code in subprocess Patch 1225 Tal Einat modified from IDLE-Spoon. ........ r58399 | brett.cannon | 2007-10-09 17:07:50 -0700 (Tue, 09 Oct 2007) | 5 lines Remove file-level typedefs that were inconsistently used throughout the file. Just move over to the public API names. Closes issue1238. ........ r58401 | raymond.hettinger | 2007-10-09 17:26:46 -0700 (Tue, 09 Oct 2007) | 1 line Accept Jim Jewett's api suggestion to use None instead of -1 to indicate unbounded deques. ........ r58403 | kurt.kaiser | 2007-10-09 17:55:40 -0700 (Tue, 09 Oct 2007) | 2 lines Allow cursor color change w/o restart. Patch 1725576 Tal Einat. ........ r58404 | kurt.kaiser | 2007-10-09 18:06:47 -0700 (Tue, 09 Oct 2007) | 2 lines show paste if > 80 columns. Patch 1659326 Tal Einat. ........ r58415 | thomas.heller | 2007-10-11 12:51:32 -0700 (Thu, 11 Oct 2007) | 5 lines On OS X, use os.uname() instead of gestalt.sysv(...) to get the operating system version. This allows to use ctypes when Python was configured with --disable-toolbox-glue. ........ r58419 | neal.norwitz | 2007-10-11 20:01:01 -0700 (Thu, 11 Oct 2007) | 1 line Get rid of warning about not being able to create an existing directory. ........ r58420 | neal.norwitz | 2007-10-11 20:01:30 -0700 (Thu, 11 Oct 2007) | 1 line Get rid of warnings on a bunch of platforms by using a proper prototype. ........ r58421 | neal.norwitz | 2007-10-11 20:01:54 -0700 (Thu, 11 Oct 2007) | 4 lines Get rid of compiler warning about retval being used (returned) without being initialized. (gcc warning and Coverity 202) ........ r58422 | neal.norwitz | 2007-10-11 20:03:23 -0700 (Thu, 11 Oct 2007) | 1 line Fix Coverity 168: Close the file before returning (exiting). ........ r58423 | neal.norwitz | 2007-10-11 20:04:18 -0700 (Thu, 11 Oct 2007) | 4 lines Fix Coverity 180: Don't overallocate. We don't need structs, but pointers. Also fix a memory leak. ........ r58424 | neal.norwitz | 2007-10-11 20:05:19 -0700 (Thu, 11 Oct 2007) | 5 lines Fix Coverity 185-186: If the passed in FILE is NULL, uninitialized memory would be accessed. Will backport. ........ r58425 | neal.norwitz | 2007-10-11 20:52:34 -0700 (Thu, 11 Oct 2007) | 1 line Get this module to compile with bsddb versions prior to 4.3 ........ r58430 | martin.v.loewis | 2007-10-12 01:56:52 -0700 (Fri, 12 Oct 2007) | 3 lines Bug #1216: Restore support for Visual Studio 2002. Will backport to 2.5. ........ r58433 | raymond.hettinger | 2007-10-12 10:53:11 -0700 (Fri, 12 Oct 2007) | 1 line Fix test of count.__repr__() to ignore the 'L' if the count is a long ........ r58434 | gregory.p.smith | 2007-10-12 11:44:06 -0700 (Fri, 12 Oct 2007) | 4 lines Fixes http://bugs.python.org/issue1233 - bsddb.dbshelve.DBShelf.append was useless due to inverted logic. Also adds a test case for RECNO dbs to test_dbshelve. ........ r58445 | georg.brandl | 2007-10-13 06:20:03 -0700 (Sat, 13 Oct 2007) | 2 lines Fix email example. ........ r58450 | gregory.p.smith | 2007-10-13 16:02:05 -0700 (Sat, 13 Oct 2007) | 2 lines Fix an uncollectable reference leak in bsddb.db.DBShelf.append ........ r58453 | neal.norwitz | 2007-10-13 17:18:40 -0700 (Sat, 13 Oct 2007) | 8 lines Let the O/S supply a port if none of the default ports can be used. This should make the tests more robust at the expense of allowing tests to be sloppier by not requiring them to cleanup after themselves. (It will legitamitely help when running two test suites simultaneously or if another process is already using one of the predefined ports.) Also simplifies (slightLy) the exception handling elsewhere. ........ r58459 | neal.norwitz | 2007-10-14 11:30:21 -0700 (Sun, 14 Oct 2007) | 2 lines Don't raise a string exception, they don't work anymore. ........ r58460 | neal.norwitz | 2007-10-14 11:40:37 -0700 (Sun, 14 Oct 2007) | 1 line Use unittest for assertions ........ r58468 | armin.rigo | 2007-10-15 00:48:35 -0700 (Mon, 15 Oct 2007) | 2 lines test_bigbits was not testing what it seemed to. ........ r58471 | guido.van.rossum | 2007-10-15 08:54:11 -0700 (Mon, 15 Oct 2007) | 3 lines Change a PyErr_Print() into a PyErr_Clear(), per discussion in issue 1031213. ........ r58500 | raymond.hettinger | 2007-10-16 12:18:30 -0700 (Tue, 16 Oct 2007) | 1 line Improve error messages ........ r58506 | raymond.hettinger | 2007-10-16 14:28:32 -0700 (Tue, 16 Oct 2007) | 1 line More docs, error messages, and tests ........ r58507 | andrew.kuchling | 2007-10-16 15:58:03 -0700 (Tue, 16 Oct 2007) | 1 line Add items ........ r58508 | brett.cannon | 2007-10-16 16:24:06 -0700 (Tue, 16 Oct 2007) | 3 lines Remove ``:const:`` notation on None in parameter list. Since the markup is not rendered for parameters it just showed up as ``:const:`None` `` in the output. ........ r58509 | brett.cannon | 2007-10-16 16:26:45 -0700 (Tue, 16 Oct 2007) | 3 lines Re-order some functions whose parameters differ between PyObject and const char * so that they are next to each other. ........ r58522 | armin.rigo | 2007-10-17 11:46:37 -0700 (Wed, 17 Oct 2007) | 5 lines Fix the overflow checking of list_repeat. Introduce overflow checking into list_inplace_repeat. Backport candidate, possibly. ........ r58530 | facundo.batista | 2007-10-17 20:16:03 -0700 (Wed, 17 Oct 2007) | 7 lines Issue #1580738. When HTTPConnection reads the whole stream with read(), it closes itself. When the stream is read in several calls to read(n), it should behave in the same way if HTTPConnection knows where the end of the stream is (through self.length). Added a test case for this behaviour. ........ r58531 | facundo.batista | 2007-10-17 20:44:48 -0700 (Wed, 17 Oct 2007) | 3 lines Issue 1289, just a typo. ........ r58532 | gregory.p.smith | 2007-10-18 00:56:54 -0700 (Thu, 18 Oct 2007) | 4 lines cleanup test_dbtables to use mkdtemp. cleanup dbtables to pass txn as a keyword argument whenever possible to avoid bugs and confusion. (dbtables.py line 447 self.db.get using txn as a non-keyword was an actual bug due to this) ........ r58533 | gregory.p.smith | 2007-10-18 01:34:20 -0700 (Thu, 18 Oct 2007) | 4 lines Fix a weird bug in dbtables: if it chose a random rowid string that contained NULL bytes it would cause the database all sorts of problems in the future leading to very strange random failures and corrupt dbtables.bsdTableDb dbs. ........ r58534 | gregory.p.smith | 2007-10-18 09:32:02 -0700 (Thu, 18 Oct 2007) | 3 lines A cleaner fix than the one committed last night. Generate random rowids that do not contain null bytes. ........ r58537 | gregory.p.smith | 2007-10-18 10:17:57 -0700 (Thu, 18 Oct 2007) | 2 lines mention bsddb fixes. ........ r58538 | raymond.hettinger | 2007-10-18 14:13:06 -0700 (Thu, 18 Oct 2007) | 1 line Remove useless warning ........ r58539 | gregory.p.smith | 2007-10-19 00:31:20 -0700 (Fri, 19 Oct 2007) | 2 lines squelch the warning that this test is supposed to trigger. ........ r58542 | georg.brandl | 2007-10-19 05:32:39 -0700 (Fri, 19 Oct 2007) | 2 lines Clarify wording for apply(). ........ r58544 | mark.summerfield | 2007-10-19 05:48:17 -0700 (Fri, 19 Oct 2007) | 3 lines Added a cross-ref to each other. ........ r58545 | georg.brandl | 2007-10-19 10:38:49 -0700 (Fri, 19 Oct 2007) | 2 lines #1284: "S" means "seen", not unread. ........ r58548 | thomas.heller | 2007-10-19 11:11:41 -0700 (Fri, 19 Oct 2007) | 4 lines Fix ctypes on 32-bit systems when Python is configured --with-system-ffi. See also https://bugs.launchpad.net/bugs/72505. Ported from release25-maint branch. ........ r58550 | facundo.batista | 2007-10-19 12:25:57 -0700 (Fri, 19 Oct 2007) | 8 lines The constructor from tuple was way too permissive: it allowed bad coefficient numbers, floats in the sign, and other details that generated directly the wrong number in the best case, or triggered misfunctionality in the alorithms. Test cases added for these issues. Thanks Mark Dickinson. ........ r58559 | georg.brandl | 2007-10-20 06:22:53 -0700 (Sat, 20 Oct 2007) | 2 lines Fix code being interpreted as a target. ........ r58561 | georg.brandl | 2007-10-20 06:36:24 -0700 (Sat, 20 Oct 2007) | 2 lines Document new "cmdoption" directive. ........ r58562 | georg.brandl | 2007-10-20 08:21:22 -0700 (Sat, 20 Oct 2007) | 2 lines Make a path more Unix-standardy. ........ r58564 | georg.brandl | 2007-10-20 10:51:39 -0700 (Sat, 20 Oct 2007) | 2 lines Document new directive "envvar". ........ r58567 | georg.brandl | 2007-10-20 11:08:14 -0700 (Sat, 20 Oct 2007) | 6 lines * Add new toplevel chapter, "Using Python." (how to install, configure and setup python on different platforms -- at least in theory.) * Move the Python on Mac docs in that chapter. * Add a new chapter about the command line invocation, by stargaming. ........ r58568 | georg.brandl | 2007-10-20 11:33:20 -0700 (Sat, 20 Oct 2007) | 2 lines Change title, for now. ........ r58569 | georg.brandl | 2007-10-20 11:39:25 -0700 (Sat, 20 Oct 2007) | 2 lines Add entry to ACKS. ........ r58570 | georg.brandl | 2007-10-20 12:05:45 -0700 (Sat, 20 Oct 2007) | 2 lines Clarify -E docs. ........ r58571 | georg.brandl | 2007-10-20 12:08:36 -0700 (Sat, 20 Oct 2007) | 2 lines Even more clarification. ........ r58572 | andrew.kuchling | 2007-10-20 12:25:37 -0700 (Sat, 20 Oct 2007) | 1 line Fix protocol name ........ r58573 | andrew.kuchling | 2007-10-20 12:35:18 -0700 (Sat, 20 Oct 2007) | 1 line Various items ........ r58574 | andrew.kuchling | 2007-10-20 12:39:35 -0700 (Sat, 20 Oct 2007) | 1 line Use correct header line ........ r58576 | armin.rigo | 2007-10-21 02:14:15 -0700 (Sun, 21 Oct 2007) | 3 lines Add a crasher for the long-standing issue with closing a file while another thread uses it. ........ r58577 | georg.brandl | 2007-10-21 03:01:56 -0700 (Sun, 21 Oct 2007) | 2 lines Remove duplicate crasher. ........ r58578 | georg.brandl | 2007-10-21 03:24:20 -0700 (Sun, 21 Oct 2007) | 2 lines Unify "byte code" to "bytecode". Also sprinkle :term: markup for it. ........ r58579 | georg.brandl | 2007-10-21 03:32:54 -0700 (Sun, 21 Oct 2007) | 2 lines Add markup to new function descriptions. ........ r58580 | georg.brandl | 2007-10-21 03:45:46 -0700 (Sun, 21 Oct 2007) | 2 lines Add :term:s for descriptors. ........ r58581 | georg.brandl | 2007-10-21 03:46:24 -0700 (Sun, 21 Oct 2007) | 2 lines Unify "file-descriptor" to "file descriptor". ........ r58582 | georg.brandl | 2007-10-21 03:52:38 -0700 (Sun, 21 Oct 2007) | 2 lines Add :term: for generators. ........ r58583 | georg.brandl | 2007-10-21 05:10:28 -0700 (Sun, 21 Oct 2007) | 2 lines Add :term:s for iterator. ........ r58584 | georg.brandl | 2007-10-21 05:15:05 -0700 (Sun, 21 Oct 2007) | 2 lines Add :term:s for "new-style class". ........ r58588 | neal.norwitz | 2007-10-21 21:47:54 -0700 (Sun, 21 Oct 2007) | 1 line Add Chris Monson so he can edit PEPs. ........ r58594 | guido.van.rossum | 2007-10-22 09:27:19 -0700 (Mon, 22 Oct 2007) | 4 lines Issue #1307, patch by Derek Shockey. When "MAIL" is received without args, an exception happens instead of sending a 501 syntax error response. ........ r58598 | travis.oliphant | 2007-10-22 19:40:56 -0700 (Mon, 22 Oct 2007) | 1 line Add phuang patch from Issue 708374 which adds offset parameter to mmap module. ........ r58601 | neal.norwitz | 2007-10-22 22:44:27 -0700 (Mon, 22 Oct 2007) | 2 lines Bug #1313, fix typo (wrong variable name) in example. ........ r58609 | georg.brandl | 2007-10-23 11:21:35 -0700 (Tue, 23 Oct 2007) | 2 lines Update Pygments version from externals. ........ r58618 | guido.van.rossum | 2007-10-23 12:25:41 -0700 (Tue, 23 Oct 2007) | 3 lines Issue 1307 by Derek Shockey, fox the same bug for RCPT. Neal: please backport! ........ r58620 | raymond.hettinger | 2007-10-23 13:37:41 -0700 (Tue, 23 Oct 2007) | 1 line Shorter name for namedtuple() ........ r58621 | andrew.kuchling | 2007-10-23 13:55:47 -0700 (Tue, 23 Oct 2007) | 1 line Update name ........ r58622 | raymond.hettinger | 2007-10-23 14:23:07 -0700 (Tue, 23 Oct 2007) | 1 line Fixup news entry ........ r58623 | raymond.hettinger | 2007-10-23 18:28:33 -0700 (Tue, 23 Oct 2007) | 1 line Optimize sum() for integer and float inputs. ........ r58624 | raymond.hettinger | 2007-10-23 19:05:51 -0700 (Tue, 23 Oct 2007) | 1 line Fixup error return and add support for intermixed ints and floats/ ........ r58628 | vinay.sajip | 2007-10-24 03:47:06 -0700 (Wed, 24 Oct 2007) | 1 line Bug #1321: Fixed logic error in TimedRotatingFileHandler.__init__() ........ r58641 | facundo.batista | 2007-10-24 12:11:08 -0700 (Wed, 24 Oct 2007) | 4 lines Issue 1290. CharacterData.__repr__ was constructing a string in response that keeped having a non-ascii character. ........ r58643 | thomas.heller | 2007-10-24 12:50:45 -0700 (Wed, 24 Oct 2007) | 1 line Added unittest for calling a function with paramflags (backport from py3k branch). ........ r58645 | matthias.klose | 2007-10-24 13:00:44 -0700 (Wed, 24 Oct 2007) | 2 lines - Build using system ffi library on arm*-linux*. ........ r58651 | georg.brandl | 2007-10-24 14:40:38 -0700 (Wed, 24 Oct 2007) | 2 lines Bug #1287: make os.environ.pop() work as expected. ........ r58652 | raymond.hettinger | 2007-10-24 19:26:58 -0700 (Wed, 24 Oct 2007) | 1 line Missing DECREFs ........ r58653 | matthias.klose | 2007-10-24 23:37:24 -0700 (Wed, 24 Oct 2007) | 2 lines - Build using system ffi library on arm*-linux*, pass --with-system-ffi to CONFIG_ARGS ........ r58655 | thomas.heller | 2007-10-25 12:47:32 -0700 (Thu, 25 Oct 2007) | 2 lines ffi_type_longdouble may be already #defined. See issue 1324. ........ r58656 | kurt.kaiser | 2007-10-25 15:43:45 -0700 (Thu, 25 Oct 2007) | 3 lines Correct an ancient bug in an unused path by removing that path: register() is now idempotent. ........ r58660 | kurt.kaiser | 2007-10-25 17:10:09 -0700 (Thu, 25 Oct 2007) | 4 lines 1. Add comments to provide top-level documentation. 2. Refactor to use more descriptive names. 3. Enhance tests in main(). ........ r58675 | georg.brandl | 2007-10-26 11:30:41 -0700 (Fri, 26 Oct 2007) | 2 lines Fix new pop() method on os.environ on ignorecase-platforms. ........ r58696 | neal.norwitz | 2007-10-27 15:32:21 -0700 (Sat, 27 Oct 2007) | 1 line Update URL for Pygments. 0.8.1 is no longer available ........ r58697 | hyeshik.chang | 2007-10-28 04:19:02 -0700 (Sun, 28 Oct 2007) | 3 lines - Add support for FreeBSD 8 which is recently forked from FreeBSD 7. - Regenerate IN module for most recent maintenance tree of FreeBSD 6 and 7. ........ r58698 | hyeshik.chang | 2007-10-28 05:38:09 -0700 (Sun, 28 Oct 2007) | 2 lines Enable platform-specific tweaks for FreeBSD 8 (exactly same to FreeBSD 7's yet) ........ r58700 | kurt.kaiser | 2007-10-28 12:03:59 -0700 (Sun, 28 Oct 2007) | 2 lines Add confirmation dialog before printing. Patch 1717170 Tal Einat. ........ r58706 | guido.van.rossum | 2007-10-29 13:52:45 -0700 (Mon, 29 Oct 2007) | 3 lines Patch 1353 by Jacob Winther. Add mp4 mapping to mimetypes.py. ........ r58709 | guido.van.rossum | 2007-10-29 15:15:05 -0700 (Mon, 29 Oct 2007) | 6 lines Backport fixes for the code that decodes octal escapes (and for PyString also hex escapes) -- this was reaching beyond the end of the input string buffer, even though it is not supposed to be \0-terminated. This has no visible effect but is clearly the correct thing to do. (In 3.0 it had a visible effect after removing ob_sstate from PyString.) ........ r58710 | kurt.kaiser | 2007-10-29 19:38:54 -0700 (Mon, 29 Oct 2007) | 7 lines check in Tal Einat's update to tabpage.py Patch 1612746 M configDialog.py M NEWS.txt AM tabbedpages.py ........ r58715 | georg.brandl | 2007-10-30 10:51:18 -0700 (Tue, 30 Oct 2007) | 2 lines Use correct markup. ........ r58716 | georg.brandl | 2007-10-30 10:57:12 -0700 (Tue, 30 Oct 2007) | 2 lines Make example about hiding None return values at the prompt clearer. ........ r58728 | neal.norwitz | 2007-10-30 23:33:20 -0700 (Tue, 30 Oct 2007) | 1 line Fix some compiler warnings for signed comparisons on Unix and Windows. ........ r58731 | martin.v.loewis | 2007-10-31 10:19:33 -0700 (Wed, 31 Oct 2007) | 2 lines Adding Christian Heimes. ........ r58737 | raymond.hettinger | 2007-10-31 14:57:58 -0700 (Wed, 31 Oct 2007) | 1 line Clarify the reasons why pickle is almost always better than marshal ........ r58739 | raymond.hettinger | 2007-10-31 15:15:49 -0700 (Wed, 31 Oct 2007) | 1 line Sets are marshalable. ........
2007-11-01 17:32:30 -03:00
"vectorized" building blocks over the use of for-loops and :term:`generator`\s
Merged revisions 61724-61725,61731-61735,61737,61739,61741,61743-61744,61753,61761,61765-61767,61769,61773,61776-61778,61780-61783,61788,61793,61796,61807,61813 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ................ r61724 | martin.v.loewis | 2008-03-22 01:01:12 +0100 (Sat, 22 Mar 2008) | 49 lines Merged revisions 61602-61723 via svnmerge from svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3 ........ r61626 | david.wolever | 2008-03-19 17:19:16 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added fixer for implicit local imports. See #2414. ........ r61628 | david.wolever | 2008-03-19 17:57:43 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added a class for tests which should not run if a particular import is found. ........ r61629 | collin.winter | 2008-03-19 17:58:19 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Two more relative import fixes in pgen2. ........ r61635 | david.wolever | 2008-03-19 20:16:03 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Fixed print fixer so it will do the Right Thing when it encounters __future__.print_function. 2to3 gets upset, though, so the tests have been commented out. ........ r61637 | david.wolever | 2008-03-19 21:37:17 +0100 (Mi, 19 M?\195?\164r 2008) | 3 lines Added a fixer for itertools imports (from itertools import imap, ifilterfalse --> from itertools import filterfalse) ........ r61645 | david.wolever | 2008-03-19 23:22:35 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line SVN is happier when you add the files you create... -_-' ........ r61654 | david.wolever | 2008-03-20 01:09:56 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added an explicit sort order to fixers -- fixes problems like #2427 ........ r61664 | david.wolever | 2008-03-20 04:32:40 +0100 (Do, 20 M?\195?\164r 2008) | 3 lines Fixes #2428 -- comments are no longer eatten by __future__ fixer. ........ r61673 | david.wolever | 2008-03-20 17:22:40 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added 2to3 node pretty-printer ........ r61679 | david.wolever | 2008-03-20 20:50:42 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Made node printing a little bit prettier ........ r61723 | martin.v.loewis | 2008-03-22 00:59:27 +0100 (Sa, 22 M?\195?\164r 2008) | 2 lines Fix whitespace. ........ ................ r61725 | martin.v.loewis | 2008-03-22 01:02:41 +0100 (Sat, 22 Mar 2008) | 2 lines Install lib2to3. ................ r61731 | facundo.batista | 2008-03-22 03:45:37 +0100 (Sat, 22 Mar 2008) | 4 lines Small fix that complicated the test actually when that test failed. ................ r61732 | alexandre.vassalotti | 2008-03-22 05:08:44 +0100 (Sat, 22 Mar 2008) | 2 lines Added warning for the removal of 'hotshot' in Py3k. ................ r61733 | georg.brandl | 2008-03-22 11:07:29 +0100 (Sat, 22 Mar 2008) | 4 lines #1918: document that weak references *to* an object are cleared before the object's __del__ is called, to ensure that the weak reference callback (if any) finds the object healthy. ................ r61734 | georg.brandl | 2008-03-22 11:56:23 +0100 (Sat, 22 Mar 2008) | 2 lines Activate the Sphinx doctest extension and convert howto/functional to use it. ................ r61735 | georg.brandl | 2008-03-22 11:58:38 +0100 (Sat, 22 Mar 2008) | 2 lines Allow giving source names on the cmdline. ................ r61737 | georg.brandl | 2008-03-22 12:00:48 +0100 (Sat, 22 Mar 2008) | 2 lines Fixup this HOWTO's doctest blocks so that they can be run with sphinx' doctest builder. ................ r61739 | georg.brandl | 2008-03-22 12:47:10 +0100 (Sat, 22 Mar 2008) | 2 lines Test decimal.rst doctests as far as possible with sphinx doctest. ................ r61741 | georg.brandl | 2008-03-22 13:04:26 +0100 (Sat, 22 Mar 2008) | 2 lines Make doctests in re docs usable with sphinx' doctest. ................ r61743 | georg.brandl | 2008-03-22 13:59:37 +0100 (Sat, 22 Mar 2008) | 2 lines Make more doctests in pprint docs testable. ................ r61744 | georg.brandl | 2008-03-22 14:07:06 +0100 (Sat, 22 Mar 2008) | 2 lines No need to specify explicit "doctest_block" anymore. ................ r61753 | georg.brandl | 2008-03-22 21:08:43 +0100 (Sat, 22 Mar 2008) | 2 lines Fix-up syntax problems. ................ r61761 | georg.brandl | 2008-03-22 22:06:20 +0100 (Sat, 22 Mar 2008) | 4 lines Make collections' doctests executable. (The <BLANKLINE>s will be stripped from presentation output.) ................ r61765 | georg.brandl | 2008-03-22 22:21:57 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in datetime docs. ................ r61766 | georg.brandl | 2008-03-22 22:26:44 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in operator docs. ................ r61767 | georg.brandl | 2008-03-22 22:38:33 +0100 (Sat, 22 Mar 2008) | 2 lines Enable doctests in functions.rst. Already found two errors :) ................ r61769 | georg.brandl | 2008-03-22 23:04:10 +0100 (Sat, 22 Mar 2008) | 3 lines Enable doctest running for several other documents. We have now over 640 doctests that are run with "make doctest". ................ r61773 | raymond.hettinger | 2008-03-23 01:55:46 +0100 (Sun, 23 Mar 2008) | 1 line Simplify demo code. ................ r61776 | neal.norwitz | 2008-03-23 04:43:33 +0100 (Sun, 23 Mar 2008) | 7 lines Try to make this test a little more robust and not fail with: timeout (10.0025) is more than 2 seconds more than expected (0.001) I'm assuming this problem is caused by DNS lookup. This change does a DNS lookup of the hostname before trying to connect, so the time is not included. ................ r61777 | neal.norwitz | 2008-03-23 05:08:30 +0100 (Sun, 23 Mar 2008) | 1 line Speed up the test by avoiding socket timeouts. ................ r61778 | neal.norwitz | 2008-03-23 05:43:09 +0100 (Sun, 23 Mar 2008) | 1 line Skip the epoll test if epoll() does not work ................ r61780 | neal.norwitz | 2008-03-23 06:47:20 +0100 (Sun, 23 Mar 2008) | 1 line Suppress failure (to avoid a flaky test) if we cannot connect to svn.python.org ................ r61781 | neal.norwitz | 2008-03-23 07:13:25 +0100 (Sun, 23 Mar 2008) | 4 lines Move itertools before future_builtins since the latter depends on the former. From a clean build importing future_builtins would fail since itertools wasn't built yet. ................ r61782 | neal.norwitz | 2008-03-23 07:16:04 +0100 (Sun, 23 Mar 2008) | 1 line Try to prevent the alarm going off early in tearDown ................ r61783 | neal.norwitz | 2008-03-23 07:19:57 +0100 (Sun, 23 Mar 2008) | 4 lines Remove compiler warnings (on Alpha at least) about using chars as array subscripts. Using chars are dangerous b/c they are signed on some platforms and unsigned on others. ................ r61788 | georg.brandl | 2008-03-23 09:05:30 +0100 (Sun, 23 Mar 2008) | 2 lines Make the doctests presentation-friendlier. ................ r61793 | amaury.forgeotdarc | 2008-03-23 10:55:29 +0100 (Sun, 23 Mar 2008) | 4 lines #1477: ur'\U0010FFFF' raised in narrow unicode builds. Corrected the raw-unicode-escape codec to use UTF-16 surrogates in this case, just like the unicode-escape codec. ................ r61796 | raymond.hettinger | 2008-03-23 14:32:32 +0100 (Sun, 23 Mar 2008) | 1 line Issue 1681432: Add triangular distribution the random module. ................ r61807 | raymond.hettinger | 2008-03-23 20:37:53 +0100 (Sun, 23 Mar 2008) | 4 lines Adopt Nick's suggestion for useful default arguments. Clean-up floating point issues by adding true division and float constants. ................ r61813 | gregory.p.smith | 2008-03-23 22:04:43 +0100 (Sun, 23 Mar 2008) | 6 lines Fix gzip to deal with CRC's being signed values in Python 2.x properly and to read 32bit values as unsigned to start with rather than applying signedness fixups allover the place afterwards. This hopefully fixes the test_tarfile failure on the alpha/tru64 buildbot. ................
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which incur interpreter overhead.
.. testcode::
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def take(n, iterable):
"Return first n items of the iterable as a list"
return list(islice(iterable, n))
def tabulate(function, start=0):
"Return function(0), function(1), ..."
return map(function, count(start))
def tail(n, iterable):
"Return an iterator over the last n items"
# tail(3, 'ABCDEFG') --> E F G
return iter(collections.deque(iterable, maxlen=n))
def consume(iterator, n):
"Advance the iterator n-steps ahead. If n is none, consume entirely."
# Use functions that consume iterators at C speed.
if n is None:
# feed the entire iterator into a zero-length deque
collections.deque(iterator, maxlen=0)
else:
# advance to the empty slice starting at position n
next(islice(iterator, n, n), None)
def nth(iterable, n, default=None):
"Returns the nth item or a default value"
return next(islice(iterable, n, None), default)
def all_equal(iterable):
"Returns True if all the elements are equal to each other"
g = groupby(iterable)
return next(g, True) and not next(g, False)
def quantify(iterable, pred=bool):
"Count how many times the predicate is true"
return sum(map(pred, iterable))
def padnone(iterable):
"""Returns the sequence elements and then returns None indefinitely.
Useful for emulating the behavior of the built-in map() function.
"""
return chain(iterable, repeat(None))
def ncycles(iterable, n):
"Returns the sequence elements n times"
return chain.from_iterable(repeat(tuple(iterable), n))
def dotproduct(vec1, vec2):
return sum(map(operator.mul, vec1, vec2))
def flatten(listOfLists):
"Flatten one level of nesting"
return chain.from_iterable(listOfLists)
def repeatfunc(func, times=None, *args):
"""Repeat calls to func with specified arguments.
Example: repeatfunc(random.random)
"""
if times is None:
return starmap(func, repeat(args))
return starmap(func, repeat(args, times))
def pairwise(iterable):
"s -> (s0,s1), (s1,s2), (s2, s3), ..."
a, b = tee(iterable)
next(b, None)
return zip(a, b)
def grouper(iterable, n, fillvalue=None):
"Collect data into fixed-length chunks or blocks"
# grouper('ABCDEFG', 3, 'x') --> ABC DEF Gxx"
args = [iter(iterable)] * n
return zip_longest(*args, fillvalue=fillvalue)
def roundrobin(*iterables):
"roundrobin('ABC', 'D', 'EF') --> A D E B F C"
# Recipe credited to George Sakkis
pending = len(iterables)
nexts = cycle(iter(it).__next__ for it in iterables)
while pending:
try:
for next in nexts:
yield next()
except StopIteration:
pending -= 1
nexts = cycle(islice(nexts, pending))
def partition(pred, iterable):
'Use a predicate to partition entries into false entries and true entries'
# partition(is_odd, range(10)) --> 0 2 4 6 8 and 1 3 5 7 9
t1, t2 = tee(iterable)
return filterfalse(pred, t1), filter(pred, t2)
def powerset(iterable):
"powerset([1,2,3]) --> () (1,) (2,) (3,) (1,2) (1,3) (2,3) (1,2,3)"
s = list(iterable)
return chain.from_iterable(combinations(s, r) for r in range(len(s)+1))
def unique_everseen(iterable, key=None):
"List unique elements, preserving order. Remember all elements ever seen."
# unique_everseen('AAAABBBCCDAABBB') --> A B C D
# unique_everseen('ABBCcAD', str.lower) --> A B C D
seen = set()
seen_add = seen.add
if key is None:
for element in filterfalse(seen.__contains__, iterable):
seen_add(element)
yield element
else:
for element in iterable:
k = key(element)
if k not in seen:
seen_add(k)
yield element
def unique_justseen(iterable, key=None):
"List unique elements, preserving order. Remember only the element just seen."
# unique_justseen('AAAABBBCCDAABBB') --> A B C D A B
# unique_justseen('ABBCcAD', str.lower) --> A B C A D
return map(next, map(itemgetter(1), groupby(iterable, key)))
def iter_except(func, exception, first=None):
""" Call a function repeatedly until an exception is raised.
Converts a call-until-exception interface to an iterator interface.
Like builtins.iter(func, sentinel) but uses an exception instead
of a sentinel to end the loop.
Examples:
iter_except(functools.partial(heappop, h), IndexError) # priority queue iterator
iter_except(d.popitem, KeyError) # non-blocking dict iterator
iter_except(d.popleft, IndexError) # non-blocking deque iterator
iter_except(q.get_nowait, Queue.Empty) # loop over a producer Queue
iter_except(s.pop, KeyError) # non-blocking set iterator
"""
try:
if first is not None:
yield first() # For database APIs needing an initial cast to db.first()
while True:
yield func()
except exception:
pass
def first_true(iterable, default=False, pred=None):
"""Returns the first true value in the iterable.
If no true value is found, returns *default*
If *pred* is not None, returns the first item
for which pred(item) is true.
"""
# first_true([a,b,c], x) --> a or b or c or x
# first_true([a,b], x, f) --> a if f(a) else b if f(b) else x
return next(filter(pred, iterable), default)
def random_product(*args, repeat=1):
"Random selection from itertools.product(*args, **kwds)"
pools = [tuple(pool) for pool in args] * repeat
return tuple(random.choice(pool) for pool in pools)
def random_permutation(iterable, r=None):
"Random selection from itertools.permutations(iterable, r)"
pool = tuple(iterable)
r = len(pool) if r is None else r
return tuple(random.sample(pool, r))
def random_combination(iterable, r):
"Random selection from itertools.combinations(iterable, r)"
pool = tuple(iterable)
n = len(pool)
indices = sorted(random.sample(range(n), r))
return tuple(pool[i] for i in indices)
def random_combination_with_replacement(iterable, r):
"Random selection from itertools.combinations_with_replacement(iterable, r)"
pool = tuple(iterable)
n = len(pool)
indices = sorted(random.randrange(n) for i in range(r))
return tuple(pool[i] for i in indices)
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Note, many of the above recipes can be optimized by replacing global lookups
with local variables defined as default values. For example, the
*dotproduct* recipe can be written as::
def dotproduct(vec1, vec2, sum=sum, map=map, mul=operator.mul):
return sum(map(mul, vec1, vec2))