2007-08-15 22:28:22 +08:00
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:mod:`heapq` --- Heap queue algorithm
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=====================================
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.. module:: heapq
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:synopsis: Heap queue algorithm (a.k.a. priority queue).
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2016-06-12 03:02:54 +08:00
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2007-08-15 22:28:22 +08:00
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.. moduleauthor:: Kevin O'Connor
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.. sectionauthor:: Guido van Rossum <guido@python.org>
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.. sectionauthor:: François Pinard
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2010-08-08 07:31:27 +08:00
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.. sectionauthor:: Raymond Hettinger
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2007-08-15 22:28:22 +08:00
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2011-01-10 11:26:08 +08:00
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**Source code:** :source:`Lib/heapq.py`
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2011-01-11 03:54:11 +08:00
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--------------
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2007-08-15 22:28:22 +08:00
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This module provides an implementation of the heap queue algorithm, also known
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as the priority queue algorithm.
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2010-11-23 16:37:54 +08:00
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Heaps are binary trees for which every parent node has a value less than or
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equal to any of its children. This implementation uses arrays for which
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``heap[k] <= heap[2*k+1]`` and ``heap[k] <= heap[2*k+2]`` for all *k*, counting
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elements from zero. For the sake of comparison, non-existing elements are
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considered to be infinite. The interesting property of a heap is that its
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smallest element is always the root, ``heap[0]``.
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2007-08-15 22:28:22 +08:00
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The API below differs from textbook heap algorithms in two aspects: (a) We use
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zero-based indexing. This makes the relationship between the index for a node
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and the indexes for its children slightly less obvious, but is more suitable
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since Python uses zero-based indexing. (b) Our pop method returns the smallest
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item, not the largest (called a "min heap" in textbooks; a "max heap" is more
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common in texts because of its suitability for in-place sorting).
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These two make it possible to view the heap as a regular Python list without
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surprises: ``heap[0]`` is the smallest item, and ``heap.sort()`` maintains the
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heap invariant!
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To create a heap, use a list initialized to ``[]``, or you can transform a
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populated list into a heap via function :func:`heapify`.
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The following functions are provided:
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.. function:: heappush(heap, item)
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Push the value *item* onto the *heap*, maintaining the heap invariant.
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.. function:: heappop(heap)
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Pop and return the smallest item from the *heap*, maintaining the heap
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2015-03-15 11:14:23 +08:00
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invariant. If the heap is empty, :exc:`IndexError` is raised. To access the
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smallest item without popping it, use ``heap[0]``.
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2007-08-15 22:28:22 +08:00
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2008-04-24 10:34:53 +08:00
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Merged revisions 61239-61249,61252-61257,61260-61264,61269-61275,61278-61279,61285-61286,61288-61290,61298,61303-61305,61312-61314,61317,61329,61332,61344,61350-61351,61363-61376,61378-61379,61382-61383,61387-61388,61392,61395-61396,61402-61403 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
........
r61239 | andrew.kuchling | 2008-03-05 01:44:41 +0100 (Wed, 05 Mar 2008) | 1 line
Add more items; add fragmentary notes
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r61240 | amaury.forgeotdarc | 2008-03-05 02:50:33 +0100 (Wed, 05 Mar 2008) | 13 lines
Issue#2238: some syntax errors from *args or **kwargs expressions
would give bogus error messages, because of untested exceptions::
>>> f(**g(1=2))
XXX undetected error
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: 'int' object is not iterable
instead of the expected SyntaxError: keyword can't be an expression
Will backport.
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r61241 | neal.norwitz | 2008-03-05 06:10:48 +0100 (Wed, 05 Mar 2008) | 3 lines
Remove the files/dirs after closing the DB so the tests work on Windows.
Patch from Trent Nelson. Also simplified removing a file by using test_support.
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r61242 | neal.norwitz | 2008-03-05 06:14:18 +0100 (Wed, 05 Mar 2008) | 3 lines
Get this test to pass even when there is no sound card in the system.
Patch from Trent Nelson. (I can't test this.)
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r61243 | neal.norwitz | 2008-03-05 06:20:44 +0100 (Wed, 05 Mar 2008) | 3 lines
Catch OSError when trying to remove a file in case removal fails. This
should prevent a failure in tearDown masking any real test failure.
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r61244 | neal.norwitz | 2008-03-05 06:38:06 +0100 (Wed, 05 Mar 2008) | 5 lines
Make the timeout longer to give slow machines a chance to pass the test
before timing out. This doesn't change the duration of the test under
normal circumstances. This is targetted at fixing the spurious failures
on the FreeBSD buildbot primarily.
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r61245 | neal.norwitz | 2008-03-05 06:49:03 +0100 (Wed, 05 Mar 2008) | 1 line
Tabs -> spaces
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r61246 | neal.norwitz | 2008-03-05 06:50:20 +0100 (Wed, 05 Mar 2008) | 1 line
Use -u urlfetch to run more tests
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r61247 | neal.norwitz | 2008-03-05 06:51:20 +0100 (Wed, 05 Mar 2008) | 1 line
test_smtplib sometimes reports leaks too, suppress it
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r61248 | jeffrey.yasskin | 2008-03-05 07:19:56 +0100 (Wed, 05 Mar 2008) | 5 lines
Fix test_socketserver on Windows after r61099 added several signal.alarm()
calls (which don't exist on non-Unix platforms).
Thanks to Trent Nelson for the report and patch.
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r61249 | georg.brandl | 2008-03-05 08:10:35 +0100 (Wed, 05 Mar 2008) | 2 lines
Fix some rst.
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r61252 | thomas.heller | 2008-03-05 15:53:39 +0100 (Wed, 05 Mar 2008) | 2 lines
News entry for yesterdays commit.
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r61253 | thomas.heller | 2008-03-05 16:34:29 +0100 (Wed, 05 Mar 2008) | 3 lines
Issue 1872: Changed the struct module typecode from 't' to '?', for
compatibility with PEP3118.
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r61254 | skip.montanaro | 2008-03-05 17:41:09 +0100 (Wed, 05 Mar 2008) | 4 lines
Elaborate on the role of the altinstall target when installing multiple
versions.
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r61255 | georg.brandl | 2008-03-05 20:31:44 +0100 (Wed, 05 Mar 2008) | 2 lines
#2239: PYTHONPATH delimiter is os.pathsep.
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r61256 | raymond.hettinger | 2008-03-05 21:59:58 +0100 (Wed, 05 Mar 2008) | 1 line
C implementation of itertools.permutations().
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r61257 | raymond.hettinger | 2008-03-05 22:04:32 +0100 (Wed, 05 Mar 2008) | 1 line
Small code cleanup.
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r61260 | martin.v.loewis | 2008-03-05 23:24:31 +0100 (Wed, 05 Mar 2008) | 2 lines
cd PCbuild only after deleting all pyc files.
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r61261 | raymond.hettinger | 2008-03-06 02:15:52 +0100 (Thu, 06 Mar 2008) | 1 line
Add examples.
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r61262 | andrew.kuchling | 2008-03-06 02:36:27 +0100 (Thu, 06 Mar 2008) | 1 line
Add two items
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r61263 | georg.brandl | 2008-03-06 07:47:18 +0100 (Thu, 06 Mar 2008) | 2 lines
#1725737: ignore other VC directories other than CVS and SVN's too.
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r61264 | martin.v.loewis | 2008-03-06 07:55:22 +0100 (Thu, 06 Mar 2008) | 4 lines
Patch #2232: os.tmpfile might fail on Windows if the user has no
permission to create files in the root directory.
Will backport to 2.5.
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r61269 | georg.brandl | 2008-03-06 08:19:15 +0100 (Thu, 06 Mar 2008) | 2 lines
Expand on re.split behavior with captured expressions.
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r61270 | georg.brandl | 2008-03-06 08:22:09 +0100 (Thu, 06 Mar 2008) | 2 lines
Little clarification of assignments.
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r61271 | georg.brandl | 2008-03-06 08:31:34 +0100 (Thu, 06 Mar 2008) | 2 lines
Add isinstance/issubclass to tutorial.
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r61272 | georg.brandl | 2008-03-06 08:34:52 +0100 (Thu, 06 Mar 2008) | 2 lines
Add missing NEWS entry for r61263.
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r61273 | georg.brandl | 2008-03-06 08:41:16 +0100 (Thu, 06 Mar 2008) | 2 lines
#2225: return nonzero status code from py_compile if not all files could be compiled.
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r61274 | georg.brandl | 2008-03-06 08:43:02 +0100 (Thu, 06 Mar 2008) | 2 lines
#2220: handle matching failure more gracefully.
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r61275 | georg.brandl | 2008-03-06 08:45:52 +0100 (Thu, 06 Mar 2008) | 2 lines
Bug #2220: handle rlcompleter attribute match failure more gracefully.
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r61278 | martin.v.loewis | 2008-03-06 14:49:47 +0100 (Thu, 06 Mar 2008) | 1 line
Rely on x64 platform configuration when building _bsddb on AMD64.
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r61279 | martin.v.loewis | 2008-03-06 14:50:28 +0100 (Thu, 06 Mar 2008) | 1 line
Update db-4.4.20 build procedure.
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r61285 | raymond.hettinger | 2008-03-06 21:52:01 +0100 (Thu, 06 Mar 2008) | 1 line
More tests.
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r61286 | raymond.hettinger | 2008-03-06 23:51:36 +0100 (Thu, 06 Mar 2008) | 1 line
Issue 2246: itertools grouper object did not participate in GC (should be backported).
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r61288 | raymond.hettinger | 2008-03-07 02:33:20 +0100 (Fri, 07 Mar 2008) | 1 line
Tweak recipes and tests
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r61289 | jeffrey.yasskin | 2008-03-07 07:22:15 +0100 (Fri, 07 Mar 2008) | 5 lines
Progress on issue #1193577 by adding a polling .shutdown() method to
SocketServers. The core of the patch was written by Pedro Werneck, but any bugs
are mine. I've also rearranged the code for timeouts in order to avoid
interfering with the shutdown poll.
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r61290 | nick.coghlan | 2008-03-07 15:13:28 +0100 (Fri, 07 Mar 2008) | 1 line
Speed up with statements by storing the __exit__ method on the stack instead of in a temp variable (bumps the magic number for pyc files)
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r61298 | andrew.kuchling | 2008-03-07 22:09:23 +0100 (Fri, 07 Mar 2008) | 1 line
Grammar fix
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r61303 | georg.brandl | 2008-03-08 10:54:06 +0100 (Sat, 08 Mar 2008) | 2 lines
#2253: fix continue vs. finally docs.
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r61304 | marc-andre.lemburg | 2008-03-08 11:01:43 +0100 (Sat, 08 Mar 2008) | 3 lines
Add new name for Mandrake: Mandriva.
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r61305 | georg.brandl | 2008-03-08 11:05:24 +0100 (Sat, 08 Mar 2008) | 2 lines
#1533486: fix types in refcount intro.
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r61312 | facundo.batista | 2008-03-08 17:50:27 +0100 (Sat, 08 Mar 2008) | 5 lines
Issue 1106316. post_mortem()'s parameter, traceback, is now
optional: it defaults to the traceback of the exception that is currently
being handled.
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r61313 | jeffrey.yasskin | 2008-03-08 19:26:54 +0100 (Sat, 08 Mar 2008) | 2 lines
Add tests for with and finally performance to pybench.
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r61314 | jeffrey.yasskin | 2008-03-08 21:08:21 +0100 (Sat, 08 Mar 2008) | 2 lines
Fix pybench for pythons < 2.6, tested back to 2.3.
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r61317 | jeffrey.yasskin | 2008-03-08 22:35:15 +0100 (Sat, 08 Mar 2008) | 3 lines
Well that was dumb. platform.python_implementation returns a function, not a
string.
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r61329 | georg.brandl | 2008-03-09 16:11:39 +0100 (Sun, 09 Mar 2008) | 2 lines
#2249: document assertTrue and assertFalse.
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r61332 | neal.norwitz | 2008-03-09 20:03:42 +0100 (Sun, 09 Mar 2008) | 4 lines
Introduce a lock to fix a race condition which caused an exception in the test.
Some buildbots were consistently failing (e.g., amd64).
Also remove a couple of semi-colons.
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r61344 | raymond.hettinger | 2008-03-11 01:19:07 +0100 (Tue, 11 Mar 2008) | 1 line
Add recipe to docs.
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r61350 | guido.van.rossum | 2008-03-11 22:18:06 +0100 (Tue, 11 Mar 2008) | 3 lines
Fix the overflows in expandtabs(). "This time for sure!"
(Exploit at request.)
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r61351 | raymond.hettinger | 2008-03-11 22:37:46 +0100 (Tue, 11 Mar 2008) | 1 line
Improve docs for itemgetter(). Show that it works with slices.
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r61363 | georg.brandl | 2008-03-13 08:15:56 +0100 (Thu, 13 Mar 2008) | 2 lines
#2265: fix example.
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r61364 | georg.brandl | 2008-03-13 08:17:14 +0100 (Thu, 13 Mar 2008) | 2 lines
#2270: fix typo.
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r61365 | georg.brandl | 2008-03-13 08:21:41 +0100 (Thu, 13 Mar 2008) | 2 lines
#1720705: add docs about import/threading interaction, wording by Nick.
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r61366 | andrew.kuchling | 2008-03-13 12:07:35 +0100 (Thu, 13 Mar 2008) | 1 line
Add class decorators
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r61367 | raymond.hettinger | 2008-03-13 17:43:17 +0100 (Thu, 13 Mar 2008) | 1 line
Add 2-to-3 support for the itertools moved to builtins or renamed.
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r61368 | raymond.hettinger | 2008-03-13 17:43:59 +0100 (Thu, 13 Mar 2008) | 1 line
Consistent tense.
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r61369 | raymond.hettinger | 2008-03-13 20:03:51 +0100 (Thu, 13 Mar 2008) | 1 line
Issue 2274: Add heapq.heappushpop().
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r61370 | raymond.hettinger | 2008-03-13 20:33:34 +0100 (Thu, 13 Mar 2008) | 1 line
Simplify the nlargest() code using heappushpop().
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r61371 | brett.cannon | 2008-03-13 21:27:00 +0100 (Thu, 13 Mar 2008) | 4 lines
Move test_thread over to unittest. Commits GHOP 237.
Thanks Benjamin Peterson for the patch.
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r61372 | brett.cannon | 2008-03-13 21:33:10 +0100 (Thu, 13 Mar 2008) | 4 lines
Move test_tokenize to doctest.
Done as GHOP 238 by Josip Dzolonga.
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r61373 | brett.cannon | 2008-03-13 21:47:41 +0100 (Thu, 13 Mar 2008) | 4 lines
Convert test_contains, test_crypt, and test_select to unittest.
Patch from GHOP 294 by David Marek.
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r61374 | brett.cannon | 2008-03-13 22:02:16 +0100 (Thu, 13 Mar 2008) | 4 lines
Move test_gdbm to use unittest.
Closes issue #1960. Thanks Giampaolo Rodola.
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r61375 | brett.cannon | 2008-03-13 22:09:28 +0100 (Thu, 13 Mar 2008) | 4 lines
Convert test_fcntl to unittest.
Closes issue #2055. Thanks Giampaolo Rodola.
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r61376 | raymond.hettinger | 2008-03-14 06:03:44 +0100 (Fri, 14 Mar 2008) | 1 line
Leave heapreplace() unchanged.
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r61378 | martin.v.loewis | 2008-03-14 14:56:09 +0100 (Fri, 14 Mar 2008) | 2 lines
Patch #2284: add -x64 option to rt.bat.
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r61379 | martin.v.loewis | 2008-03-14 14:57:59 +0100 (Fri, 14 Mar 2008) | 2 lines
Use -x64 flag.
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r61382 | brett.cannon | 2008-03-14 15:03:10 +0100 (Fri, 14 Mar 2008) | 2 lines
Remove a bad test.
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r61383 | mark.dickinson | 2008-03-14 15:23:37 +0100 (Fri, 14 Mar 2008) | 9 lines
Issue 705836: Fix struct.pack(">f", 1e40) to behave consistently
across platforms: it should now raise OverflowError on all
platforms. (Previously it raised OverflowError only on
non IEEE 754 platforms.)
Also fix the (already existing) test for this behaviour
so that it actually raises TestFailed instead of just
referencing it.
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r61387 | thomas.heller | 2008-03-14 22:06:21 +0100 (Fri, 14 Mar 2008) | 1 line
Remove unneeded initializer.
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r61388 | martin.v.loewis | 2008-03-14 22:19:28 +0100 (Fri, 14 Mar 2008) | 2 lines
Run debug version, cd to PCbuild.
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r61392 | georg.brandl | 2008-03-15 00:10:34 +0100 (Sat, 15 Mar 2008) | 2 lines
Remove obsolete paragraph. #2288.
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r61395 | georg.brandl | 2008-03-15 01:20:19 +0100 (Sat, 15 Mar 2008) | 2 lines
Fix lots of broken links in the docs, found by Sphinx' external link checker.
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r61396 | skip.montanaro | 2008-03-15 03:32:49 +0100 (Sat, 15 Mar 2008) | 1 line
note that fork and forkpty raise OSError on failure
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r61402 | skip.montanaro | 2008-03-15 17:04:45 +0100 (Sat, 15 Mar 2008) | 1 line
add %f format to datetime - issue 1158
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r61403 | skip.montanaro | 2008-03-15 17:07:11 +0100 (Sat, 15 Mar 2008) | 2 lines
.
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2008-03-16 08:07:10 +08:00
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.. function:: heappushpop(heap, item)
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Push *item* on the heap, then pop and return the smallest item from the
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*heap*. The combined action runs more efficiently than :func:`heappush`
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followed by a separate call to :func:`heappop`.
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2007-08-15 22:28:22 +08:00
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.. function:: heapify(x)
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Transform list *x* into a heap, in-place, in linear time.
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.. function:: heapreplace(heap, item)
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Pop and return the smallest item from the *heap*, and also push the new *item*.
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The heap size doesn't change. If the heap is empty, :exc:`IndexError` is raised.
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2010-09-02 05:27:31 +08:00
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This one step operation is more efficient than a :func:`heappop` followed by
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:func:`heappush` and can be more appropriate when using a fixed-size heap.
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The pop/push combination always returns an element from the heap and replaces
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it with *item*.
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2007-08-15 22:28:22 +08:00
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2010-09-02 05:27:31 +08:00
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The value returned may be larger than the *item* added. If that isn't
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desired, consider using :func:`heappushpop` instead. Its push/pop
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combination returns the smaller of the two values, leaving the larger value
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on the heap.
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Merged revisions 67531-67532,67538,67553-67554,67556-67557,67571,67574-67575,67579-67580,67591,67597,67608,67631 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
........
r67531 | georg.brandl | 2008-12-04 19:54:05 +0100 (Thu, 04 Dec 2008) | 2 lines
Add reference to enumerate() to indices example.
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r67532 | georg.brandl | 2008-12-04 19:59:16 +0100 (Thu, 04 Dec 2008) | 2 lines
Add another heapq example.
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r67538 | georg.brandl | 2008-12-04 22:28:16 +0100 (Thu, 04 Dec 2008) | 2 lines
Clarification to avoid confusing output with file descriptors.
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r67553 | georg.brandl | 2008-12-05 08:49:49 +0100 (Fri, 05 Dec 2008) | 2 lines
#4408: document regex.groups.
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r67554 | georg.brandl | 2008-12-05 08:52:26 +0100 (Fri, 05 Dec 2008) | 2 lines
#4409: fix asterisks looking like footnotes.
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r67556 | georg.brandl | 2008-12-05 09:02:17 +0100 (Fri, 05 Dec 2008) | 2 lines
#4441: improve doc for os.open() flags.
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r67557 | georg.brandl | 2008-12-05 09:06:57 +0100 (Fri, 05 Dec 2008) | 2 lines
Add an index entry for "subclassing immutable types".
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r67571 | georg.brandl | 2008-12-05 10:13:45 +0100 (Fri, 05 Dec 2008) | 2 lines
Use markup.
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r67574 | georg.brandl | 2008-12-05 10:25:32 +0100 (Fri, 05 Dec 2008) | 2 lines
#4441 followup: Add link to open() docs for Windows.
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r67575 | georg.brandl | 2008-12-05 12:34:51 +0100 (Fri, 05 Dec 2008) | 2 lines
#4544: add `dedent` to textwrap.__all__.
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r67579 | georg.brandl | 2008-12-05 16:29:39 +0100 (Fri, 05 Dec 2008) | 2 lines
#4517: add "special method" glossary entry and clarify when __getattribute__ is bypassed.
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r67580 | georg.brandl | 2008-12-05 16:32:29 +0100 (Fri, 05 Dec 2008) | 2 lines
#4478: document that copyfile() can raise Error.
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r67591 | georg.brandl | 2008-12-05 19:00:06 +0100 (Fri, 05 Dec 2008) | 2 lines
Followup to #4511: add link from decorator glossary entry to definition.
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r67597 | georg.brandl | 2008-12-05 20:03:19 +0100 (Fri, 05 Dec 2008) | 2 lines
Remove confusing sentence part.
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r67608 | georg.brandl | 2008-12-06 12:57:12 +0100 (Sat, 06 Dec 2008) | 2 lines
Follow-up to #4488: document PIPE and STDOUT properly.
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r67631 | georg.brandl | 2008-12-07 12:54:07 +0100 (Sun, 07 Dec 2008) | 2 lines
Add link to the favicon to the docs.
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2008-12-07 23:06:20 +08:00
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2009-01-04 05:18:54 +08:00
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2007-08-15 22:28:22 +08:00
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The module also offers three general purpose functions based on heaps.
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2014-05-30 17:28:36 +08:00
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.. function:: merge(*iterables, key=None, reverse=False)
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2007-08-15 22:28:22 +08:00
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Merge multiple sorted inputs into a single sorted output (for example, merge
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#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
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r58221 | georg.brandl | 2007-09-20 10:57:59 -0700 (Thu, 20 Sep 2007) | 2 lines
Patch #1181: add os.environ.clear() method.
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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".
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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.
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r58242 | georg.brandl | 2007-09-24 10:55:47 -0700 (Mon, 24 Sep 2007) | 2 lines
Fix typo and double word.
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r58245 | georg.brandl | 2007-09-24 10:59:28 -0700 (Mon, 24 Sep 2007) | 2 lines
#1196: document default radix for int().
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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.
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r58249 | andrew.kuchling | 2007-09-24 16:45:51 -0700 (Mon, 24 Sep 2007) | 1 line
Remove stray odd character; grammar fix
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r58250 | andrew.kuchling | 2007-09-24 16:46:28 -0700 (Mon, 24 Sep 2007) | 1 line
Typo fix
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r58251 | andrew.kuchling | 2007-09-24 17:09:42 -0700 (Mon, 24 Sep 2007) | 1 line
Add various items
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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.
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r58269 | vinay.sajip | 2007-09-26 22:38:51 -0700 (Wed, 26 Sep 2007) | 1 line
Change to basicConfig() to fix #1021.
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r58270 | georg.brandl | 2007-09-26 23:26:58 -0700 (Wed, 26 Sep 2007) | 2 lines
#1208: document match object's boolean value.
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r58271 | vinay.sajip | 2007-09-26 23:56:13 -0700 (Wed, 26 Sep 2007) | 1 line
Minor date change.
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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.
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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().
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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.
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r58305 | raymond.hettinger | 2007-10-03 17:20:27 -0700 (Wed, 03 Oct 2007) | 1 line
itertools.count() no longer limited to sys.maxint.
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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.
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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.
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r58308 | kurt.kaiser | 2007-10-03 19:09:17 -0700 (Wed, 03 Oct 2007) | 2 lines
Clean up EditorWindow close.
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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
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r58310 | kurt.kaiser | 2007-10-03 20:11:12 -0700 (Wed, 03 Oct 2007) | 3 lines
configDialog cleanup. Patch 1730217 Tal Einat.
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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.
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r58325 | fred.drake | 2007-10-04 19:46:12 -0700 (Thu, 04 Oct 2007) | 1 line
wrap lines to <80 characters before fixing errors
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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
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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*.
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r58330 | neal.norwitz | 2007-10-04 20:41:19 -0700 (Thu, 04 Oct 2007) | 2 lines
Fix Coverity #158: Check the correct variable.
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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)
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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.
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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
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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.
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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.
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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.
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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.
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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
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r58372 | raymond.hettinger | 2007-10-08 03:11:51 -0700 (Mon, 08 Oct 2007) | 1 line
Better variable names
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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!
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r58380 | raymond.hettinger | 2007-10-08 14:26:58 -0700 (Mon, 08 Oct 2007) | 1 line
Eliminate camelcase function name
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r58381 | andrew.kuchling | 2007-10-08 16:23:03 -0700 (Mon, 08 Oct 2007) | 1 line
Eliminate camelcase function name
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r58382 | raymond.hettinger | 2007-10-08 18:36:23 -0700 (Mon, 08 Oct 2007) | 1 line
Make the error messages more specific
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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.
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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.
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r58394 | gregory.p.smith | 2007-10-09 11:26:02 -0700 (Tue, 09 Oct 2007) | 2 lines
remove another sleepycat reference
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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.
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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.
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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.
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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.
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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.
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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.
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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)
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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).
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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.
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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.
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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
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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.
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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
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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.
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r58445 | georg.brandl | 2007-10-13 06:20:03 -0700 (Sat, 13 Oct 2007) | 2 lines
Fix email example.
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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
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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.
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r58460 | neal.norwitz | 2007-10-14 11:40:37 -0700 (Sun, 14 Oct 2007) | 1 line
Use unittest for assertions
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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.
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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.
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r58500 | raymond.hettinger | 2007-10-16 12:18:30 -0700 (Tue, 16 Oct 2007) | 1 line
Improve error messages
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r58506 | raymond.hettinger | 2007-10-16 14:28:32 -0700 (Tue, 16 Oct 2007) | 1 line
More docs, error messages, and tests
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r58507 | andrew.kuchling | 2007-10-16 15:58:03 -0700 (Tue, 16 Oct 2007) | 1 line
Add items
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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)
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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.
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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.
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r58537 | gregory.p.smith | 2007-10-18 10:17:57 -0700 (Thu, 18 Oct 2007) | 2 lines
mention bsddb fixes.
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r58538 | raymond.hettinger | 2007-10-18 14:13:06 -0700 (Thu, 18 Oct 2007) | 1 line
Remove useless warning
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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.
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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.
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r58564 | georg.brandl | 2007-10-20 10:51:39 -0700 (Sat, 20 Oct 2007) | 2 lines
Document new directive "envvar".
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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.
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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.
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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
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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.
........
2007-11-02 04:32:30 +08:00
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timestamped entries from multiple log files). Returns an :term:`iterator`
|
Merged revisions 66887,66891,66902-66903,66905-66906,66911-66913,66922,66927-66928,66936,66939-66940,66962,66964,66973 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
................
r66887 | benjamin.peterson | 2008-10-13 16:51:40 -0500 (Mon, 13 Oct 2008) | 1 line
document how to disable fixers
................
r66891 | amaury.forgeotdarc | 2008-10-14 16:47:22 -0500 (Tue, 14 Oct 2008) | 5 lines
#4122: On Windows, Py_UNICODE_ISSPACE cannot be used in an extension module:
compilation fails with "undefined reference to _Py_ascii_whitespace"
Will backport to 2.6.
................
r66902 | skip.montanaro | 2008-10-15 06:49:10 -0500 (Wed, 15 Oct 2008) | 1 line
easter egg
................
r66903 | benjamin.peterson | 2008-10-15 15:34:09 -0500 (Wed, 15 Oct 2008) | 1 line
don't recurse into directories that start with '.'
................
r66905 | benjamin.peterson | 2008-10-15 16:05:55 -0500 (Wed, 15 Oct 2008) | 1 line
support the optional line argument for idle
................
r66906 | benjamin.peterson | 2008-10-15 16:58:46 -0500 (Wed, 15 Oct 2008) | 1 line
add a much requested newline
................
r66911 | benjamin.peterson | 2008-10-15 18:10:28 -0500 (Wed, 15 Oct 2008) | 41 lines
Merged revisions 66805,66841,66860,66884-66886,66893,66907,66910 via svnmerge from
svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3
........
r66805 | benjamin.peterson | 2008-10-04 20:11:02 -0500 (Sat, 04 Oct 2008) | 1 line
mention what the fixes directory is for
........
r66841 | benjamin.peterson | 2008-10-07 17:48:12 -0500 (Tue, 07 Oct 2008) | 1 line
use assertFalse and assertTrue
........
r66860 | benjamin.peterson | 2008-10-08 16:05:07 -0500 (Wed, 08 Oct 2008) | 1 line
instead of abusing the pattern matcher, use start_tree to find a next binding
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r66884 | benjamin.peterson | 2008-10-13 15:50:30 -0500 (Mon, 13 Oct 2008) | 1 line
don't print tokens to stdout when -v is given
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r66885 | benjamin.peterson | 2008-10-13 16:28:57 -0500 (Mon, 13 Oct 2008) | 1 line
add the -x option to disable fixers
........
r66886 | benjamin.peterson | 2008-10-13 16:33:53 -0500 (Mon, 13 Oct 2008) | 1 line
cut down on some crud
........
r66893 | benjamin.peterson | 2008-10-14 17:16:54 -0500 (Tue, 14 Oct 2008) | 1 line
add an optional set literal fixer
........
r66907 | benjamin.peterson | 2008-10-15 16:59:41 -0500 (Wed, 15 Oct 2008) | 1 line
don't write backup files by default
........
r66910 | benjamin.peterson | 2008-10-15 17:43:10 -0500 (Wed, 15 Oct 2008) | 1 line
add the -n option; it stops backupfiles from being written
........
................
r66912 | hirokazu.yamamoto | 2008-10-16 01:25:25 -0500 (Thu, 16 Oct 2008) | 2 lines
removed unused _PyUnicode_FromFileSystemEncodedObject.
made win32_chdir, win32_wchdir static.
................
r66913 | benjamin.peterson | 2008-10-16 13:52:14 -0500 (Thu, 16 Oct 2008) | 1 line
document that deque indexing is O(n) #4123
................
r66922 | benjamin.peterson | 2008-10-16 14:40:14 -0500 (Thu, 16 Oct 2008) | 1 line
use new showwarnings signature for idle #3391
................
r66927 | andrew.kuchling | 2008-10-16 15:15:47 -0500 (Thu, 16 Oct 2008) | 1 line
Fix wording (2.6.1 backport candidate)
................
r66928 | georg.brandl | 2008-10-16 15:20:56 -0500 (Thu, 16 Oct 2008) | 2 lines
Add more TOC to the whatsnew index page.
................
r66936 | georg.brandl | 2008-10-16 16:20:15 -0500 (Thu, 16 Oct 2008) | 2 lines
#4131: FF3 doesn't write cookies.txt files.
................
r66939 | georg.brandl | 2008-10-16 16:36:39 -0500 (Thu, 16 Oct 2008) | 2 lines
part of #4012: kill off old name "processing".
................
r66940 | georg.brandl | 2008-10-16 16:38:48 -0500 (Thu, 16 Oct 2008) | 2 lines
#4083: add "as" to except handler grammar as per PEP 3110.
................
r66962 | benjamin.peterson | 2008-10-17 15:01:01 -0500 (Fri, 17 Oct 2008) | 1 line
clarify CALL_FUNCTION #4141
................
r66964 | georg.brandl | 2008-10-17 16:41:49 -0500 (Fri, 17 Oct 2008) | 2 lines
Fix duplicate word.
................
r66973 | armin.ronacher | 2008-10-19 03:27:43 -0500 (Sun, 19 Oct 2008) | 3 lines
Fixed #4067 by implementing _attributes and _fields for the AST root node.
................
2008-10-19 22:07:49 +08:00
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over the sorted values.
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2007-08-15 22:28:22 +08:00
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Similar to ``sorted(itertools.chain(*iterables))`` but returns an iterable, does
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not pull the data into memory all at once, and assumes that each of the input
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streams is already sorted (smallest to largest).
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2014-05-30 17:28:36 +08:00
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Has two optional arguments which must be specified as keyword arguments.
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*key* specifies a :term:`key function` of one argument that is used to
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extract a comparison key from each input element. The default value is
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``None`` (compare the elements directly).
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*reverse* is a boolean value. If set to ``True``, then the input elements
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2017-03-06 00:56:05 +08:00
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are merged as if each comparison were reversed. To achieve behavior similar
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to ``sorted(itertools.chain(*iterables), reverse=True)``, all iterables must
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be sorted from largest to smallest.
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2014-05-30 17:28:36 +08:00
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.. versionchanged:: 3.5
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Added the optional *key* and *reverse* parameters.
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2007-08-15 22:28:22 +08:00
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2009-05-17 21:00:36 +08:00
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.. function:: nlargest(n, iterable, key=None)
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Return a list with the *n* largest elements from the dataset defined by
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*iterable*. *key*, if provided, specifies a function of one argument that is
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2018-10-16 03:06:53 +08:00
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used to extract a comparison key from each element in *iterable* (for example,
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``key=str.lower``). Equivalent to: ``sorted(iterable, key=key,
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reverse=True)[:n]``.
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2007-08-15 22:28:22 +08:00
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2009-05-17 21:00:36 +08:00
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.. function:: nsmallest(n, iterable, key=None)
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Return a list with the *n* smallest elements from the dataset defined by
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*iterable*. *key*, if provided, specifies a function of one argument that is
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2018-10-16 03:06:53 +08:00
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used to extract a comparison key from each element in *iterable* (for example,
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``key=str.lower``). Equivalent to: ``sorted(iterable, key=key)[:n]``.
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2007-08-15 22:28:22 +08:00
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The latter two functions perform best for smaller values of *n*. For larger
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values, it is more efficient to use the :func:`sorted` function. Also, when
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2009-07-26 22:54:51 +08:00
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``n==1``, it is more efficient to use the built-in :func:`min` and :func:`max`
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2015-03-15 11:14:23 +08:00
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functions. If repeated usage of these functions is required, consider turning
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the iterable into an actual heap.
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2007-08-15 22:28:22 +08:00
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2010-09-02 05:27:31 +08:00
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Basic Examples
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--------------
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2016-02-27 02:37:12 +08:00
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A `heapsort <https://en.wikipedia.org/wiki/Heapsort>`_ can be implemented by
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2010-09-02 05:27:31 +08:00
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pushing all values onto a heap and then popping off the smallest values one at a
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time::
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>>> def heapsort(iterable):
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... h = []
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... for value in iterable:
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... heappush(h, value)
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... return [heappop(h) for i in range(len(h))]
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...
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>>> heapsort([1, 3, 5, 7, 9, 2, 4, 6, 8, 0])
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[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
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2014-10-28 19:57:11 +08:00
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This is similar to ``sorted(iterable)``, but unlike :func:`sorted`, this
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implementation is not stable.
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2010-09-02 05:27:31 +08:00
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Heap elements can be tuples. This is useful for assigning comparison values
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(such as task priorities) alongside the main record being tracked::
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>>> h = []
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>>> heappush(h, (5, 'write code'))
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>>> heappush(h, (7, 'release product'))
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>>> heappush(h, (1, 'write spec'))
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>>> heappush(h, (3, 'create tests'))
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>>> heappop(h)
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(1, 'write spec')
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2010-08-08 07:31:27 +08:00
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Priority Queue Implementation Notes
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-----------------------------------
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2016-02-27 02:37:12 +08:00
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A `priority queue <https://en.wikipedia.org/wiki/Priority_queue>`_ is common use
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2010-08-08 07:31:27 +08:00
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for a heap, and it presents several implementation challenges:
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* Sort stability: how do you get two tasks with equal priorities to be returned
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in the order they were originally added?
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* Tuple comparison breaks for (priority, task) pairs if the priorities are equal
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and the tasks do not have a default comparison order.
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2010-08-08 07:37:37 +08:00
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* If the priority of a task changes, how do you move it to a new position in
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2010-08-08 07:31:27 +08:00
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the heap?
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* Or if a pending task needs to be deleted, how do you find it and remove it
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from the queue?
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A solution to the first two challenges is to store entries as 3-element list
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including the priority, an entry count, and the task. The entry count serves as
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a tie-breaker so that two tasks with the same priority are returned in the order
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they were added. And since no two entry counts are the same, the tuple
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comparison will never attempt to directly compare two tasks.
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2018-01-12 14:06:34 +08:00
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Another solution to the problem of non-comparable tasks is to create a wrapper
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class that ignores the task item and only compares the priority field::
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from dataclasses import dataclass, field
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from typing import Any
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@dataclass(order=True)
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class PrioritizedItem:
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priority: int
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item: Any=field(compare=False)
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2010-08-08 07:31:27 +08:00
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The remaining challenges revolve around finding a pending task and making
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changes to its priority or removing it entirely. Finding a task can be done
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with a dictionary pointing to an entry in the queue.
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Removing the entry or changing its priority is more difficult because it would
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break the heap structure invariants. So, a possible solution is to mark the
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entry as removed and add a new entry with the revised priority::
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pq = [] # list of entries arranged in a heap
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entry_finder = {} # mapping of tasks to entries
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REMOVED = '<removed-task>' # placeholder for a removed task
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counter = itertools.count() # unique sequence count
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def add_task(task, priority=0):
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'Add a new task or update the priority of an existing task'
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if task in entry_finder:
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remove_task(task)
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count = next(counter)
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entry = [priority, count, task]
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entry_finder[task] = entry
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2010-08-08 07:31:27 +08:00
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heappush(pq, entry)
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2011-10-10 00:28:14 +08:00
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def remove_task(task):
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'Mark an existing task as REMOVED. Raise KeyError if not found.'
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entry = entry_finder.pop(task)
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entry[-1] = REMOVED
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def pop_task():
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'Remove and return the lowest priority task. Raise KeyError if empty.'
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while pq:
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priority, count, task = heappop(pq)
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2011-10-10 00:28:14 +08:00
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if task is not REMOVED:
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del entry_finder[task]
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2010-08-08 07:31:27 +08:00
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return task
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raise KeyError('pop from an empty priority queue')
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2010-08-08 07:31:27 +08:00
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2007-08-15 22:28:22 +08:00
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Theory
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------
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Heaps are arrays for which ``a[k] <= a[2*k+1]`` and ``a[k] <= a[2*k+2]`` for all
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*k*, counting elements from 0. For the sake of comparison, non-existing
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elements are considered to be infinite. The interesting property of a heap is
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that ``a[0]`` is always its smallest element.
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The strange invariant above is meant to be an efficient memory representation
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for a tournament. The numbers below are *k*, not ``a[k]``::
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0
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1 2
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3 4 5 6
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7 8 9 10 11 12 13 14
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15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
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2016-04-15 10:14:19 +08:00
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In the tree above, each cell *k* is topping ``2*k+1`` and ``2*k+2``. In a usual
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2007-08-15 22:28:22 +08:00
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binary tournament we see in sports, each cell is the winner over the two cells
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it tops, and we can trace the winner down the tree to see all opponents s/he
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had. However, in many computer applications of such tournaments, we do not need
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to trace the history of a winner. To be more memory efficient, when a winner is
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promoted, we try to replace it by something else at a lower level, and the rule
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becomes that a cell and the two cells it tops contain three different items, but
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the top cell "wins" over the two topped cells.
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If this heap invariant is protected at all time, index 0 is clearly the overall
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winner. The simplest algorithmic way to remove it and find the "next" winner is
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to move some loser (let's say cell 30 in the diagram above) into the 0 position,
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and then percolate this new 0 down the tree, exchanging values, until the
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invariant is re-established. This is clearly logarithmic on the total number of
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items in the tree. By iterating over all items, you get an O(n log n) sort.
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A nice feature of this sort is that you can efficiently insert new items while
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the sort is going on, provided that the inserted items are not "better" than the
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last 0'th element you extracted. This is especially useful in simulation
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contexts, where the tree holds all incoming events, and the "win" condition
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2013-07-16 10:08:13 +08:00
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means the smallest scheduled time. When an event schedules other events for
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2007-08-15 22:28:22 +08:00
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execution, they are scheduled into the future, so they can easily go into the
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heap. So, a heap is a good structure for implementing schedulers (this is what
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I used for my MIDI sequencer :-).
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Various structures for implementing schedulers have been extensively studied,
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and heaps are good for this, as they are reasonably speedy, the speed is almost
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constant, and the worst case is not much different than the average case.
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However, there are other representations which are more efficient overall, yet
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the worst cases might be terrible.
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Heaps are also very useful in big disk sorts. You most probably all know that a
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2014-12-12 15:56:32 +08:00
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big sort implies producing "runs" (which are pre-sorted sequences, whose size is
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2007-08-15 22:28:22 +08:00
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usually related to the amount of CPU memory), followed by a merging passes for
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these runs, which merging is often very cleverly organised [#]_. It is very
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important that the initial sort produces the longest runs possible. Tournaments
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2014-12-12 15:56:32 +08:00
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are a good way to achieve that. If, using all the memory available to hold a
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2007-08-15 22:28:22 +08:00
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tournament, you replace and percolate items that happen to fit the current run,
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you'll produce runs which are twice the size of the memory for random input, and
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much better for input fuzzily ordered.
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Moreover, if you output the 0'th item on disk and get an input which may not fit
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in the current tournament (because the value "wins" over the last output value),
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it cannot fit in the heap, so the size of the heap decreases. The freed memory
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could be cleverly reused immediately for progressively building a second heap,
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which grows at exactly the same rate the first heap is melting. When the first
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heap completely vanishes, you switch heaps and start a new run. Clever and
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quite effective!
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In a word, heaps are useful memory structures to know. I use them in a few
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applications, and I think it is good to keep a 'heap' module around. :-)
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.. rubric:: Footnotes
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.. [#] The disk balancing algorithms which are current, nowadays, are more annoying
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than clever, and this is a consequence of the seeking capabilities of the disks.
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On devices which cannot seek, like big tape drives, the story was quite
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different, and one had to be very clever to ensure (far in advance) that each
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tape movement will be the most effective possible (that is, will best
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participate at "progressing" the merge). Some tapes were even able to read
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backwards, and this was also used to avoid the rewinding time. Believe me, real
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good tape sorts were quite spectacular to watch! From all times, sorting has
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always been a Great Art! :-)
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