Commit Graph

58 Commits

Author SHA1 Message Date
Raymond Hettinger
85c20a41df Implement and apply PEP 322, reverse iteration 2003-11-06 14:06:48 +00:00
Raymond Hettinger
411c602349 Minor fixup. "Random" was listed twice in __all__. 2003-10-12 17:14:11 +00:00
Raymond Hettinger
2f726e9093 SF bug #812202: randint is always even
* Added C coded getrandbits(k) method that runs in linear time.
* Call the new method from randrange() for ranges >= 2**53.
* Adds a warning for generators not defining getrandbits() whenever they
  have a call to randrange() with too large of a population.
2003-10-05 09:09:15 +00:00
Raymond Hettinger
66d09f1b30 SF bug #801342: Bug (documentation or real, your choice) in random.sample.
random.sample() uses one of two algorithms depending on the ratio of the
sample size to the population size.  One of the algorithms accepted any
iterable population argument so long as it defined __len__().  The other
had a stronger requirement that the population argument be indexable.

While it met the documentation specifications which insisted that the
population argument be a sequence, it made random.sample() less usable
with sets.  So, the second algorithm was modified to coerce non-indexable
iterables and dictionaries into a tuple before proceeding.
2003-09-06 04:25:54 +00:00
Raymond Hettinger
6229713221 Eliminate unnecessary eval() in tests 2003-08-30 01:24:19 +00:00
Raymond Hettinger
3081d59f92 SF bug #778964: bad seed in python 2.3 random
The default seed is time.time().
Multiplied by 256 before truncating so that fractional seconds are used.
This way, two successive calls to random.seed() are much more likely
to produce different sequences.
2003-08-09 18:30:57 +00:00
Raymond Hettinger
f8a52d38ad Removed deprecated functions 2003-08-05 12:23:19 +00:00
Raymond Hettinger
5f078ff7f0 SF bug #759889: Pickling of Random is broken
* Implement __reduce__() to support pickling.
* Add a test case to prove a successful roundtrip through pickle.
2003-06-24 20:29:04 +00:00
Tim Peters
76ca1d428f randrange(): Repaired my overly optimistic rewrite, and added comments
explaining what's wrong with the two simpler variants.
2003-06-19 03:46:46 +00:00
Tim Peters
afb8979771 randrange(): 2.3 can no longer raises OverflowError on an int() call, so
some of this code because useless, and (worse) could return a long
instead of int (in Zope that's important, because a long can't be used
as a key in an IOBTree or IIBTree).
2003-06-19 03:23:06 +00:00
Raymond Hettinger
fdbe5223b7 SF bug #753602: random.sample not properly documented
The docs were fine but the "int=int" in the function call was both
ugly and confusing.  Moved it inside the body of the function definition.
2003-06-13 07:01:51 +00:00
Raymond Hettinger
b98154e424 'sum' is no longer a good variable name. Use 'total' instead. 2003-05-24 17:26:02 +00:00
Raymond Hettinger
7b0cf76b72 * Migrate sample distribution test from random.py to test_random.py.
* Use Sets module to more clearly articulate a couple of tests.
2003-01-17 17:23:23 +00:00
Raymond Hettinger
145a4a0f10 Much clearer when super() is used. 2003-01-07 10:25:55 +00:00
Raymond Hettinger
3dd990c53a Move the statistical tests for four distributions into the unittest suite. 2003-01-05 09:20:06 +00:00
Raymond Hettinger
73ced7ee99 Correct long standing bugs in the methods for random distributions.
The range of u=random() is [0,1), so log(u) and 1/x can fail.
Fix by setting u=1-random() or by reselecting for a usable value.

Will backport.
2003-01-04 09:26:32 +00:00
Raymond Hettinger
8b9aa8dbba Remove the random=None nonsense from sample() before it gets set in stone.
It was once available so that faster generators could be substituted.  Now,
that is less necessary and preferrably done via subclassing.

Also, clarified and shortened the comments for sample().
2003-01-04 05:20:33 +00:00
Raymond Hettinger
40f6217092 SF patch 658251: Install a C implementation of the Mersenne Twister as the
core generator for random.py.
2002-12-29 23:03:38 +00:00
Raymond Hettinger
c1ac194e94 Clarify and speedup test. 2002-12-07 09:25:05 +00:00
Raymond Hettinger
311f419628 Improve comments. Clarify docs.
Replace "type(0)" with "int".
Replace "while 1" with "while True"
2002-11-18 09:01:24 +00:00
Raymond Hettinger
c0b4034b81 Improved clarity and thoroughness of docstring.
Added design notes in comments.
Used better variable names.
Eliminated the unsavory "pool[-k:]" which was an aspiring bug (for k==0).
Used if/else to show the two algorithms in parallel style.
Added one more test assertion.
2002-11-13 15:26:37 +00:00
Andrew M. Kuchling
ea002a1aff Docstring typo fix 2002-11-13 13:25:46 +00:00
Raymond Hettinger
f24eb35d18 SF patch 629637: Add sample(population, k) method to the random module.
Used for random sampling without replacement.
2002-11-12 17:41:57 +00:00
Tim Peters
9146f27b77 SF bug 594996: OverflowError in random.randrange
Loosened the acceptable 'start' and 'stop' arguments so that any
Python (bounded) ints can be used.  So, e.g., randrange(-sys.maxint-1,
sys.maxint) no longer blows up.
2002-08-16 03:41:39 +00:00
Raymond Hettinger
ef4d4bdc3c Whitespace normalized. 2002-05-23 23:58:17 +00:00
Raymond Hettinger
c32f0336e0 Deprecated Random.cunifvariate clearing bug 506647. Also, added docstrings. 2002-05-23 19:44:49 +00:00
Tim Peters
8ac1495a6a Whitespace normalization. 2002-05-23 15:15:30 +00:00
Guido van Rossum
570764ddce Use spaces, not tabs for indents.
Raymond Hettinger, beware!  This caused the Unix install to fail!
2002-05-14 14:08:12 +00:00
Raymond Hettinger
b760efb08d Closes patch 529408 deprecating random.stdgamma(). 2002-05-14 06:40:34 +00:00
Raymond Hettinger
ca6cdc2c02 Closes SF bug 527139. Moved temp variables inside guard. 2002-05-13 23:40:14 +00:00
Tim Peters
46c04e140c random.gauss() uses a piece of hidden state used by nothing else,
and the .seed() and .whseed() methods failed to reset it.  In other
words, setting the seed didn't completely determine the sequence of
results produced by random.gauss().  It does now.  Programs repeatedly
mixing calls to a seed method with calls to gauss() may see different
results now.

Bugfix candidate (random.gauss() has always been broken in this way),
despite that it may change results.
2002-05-05 20:40:00 +00:00
Neal Norwitz
f42d32cb27 BDFL agreed with Tim: rehabilitate randint(). 2002-04-13 14:41:19 +00:00
Tim Peters
dc47a89ff1 SF patch 483059: Avoid use of eval() in random.py, from Finn Bock.
_verify():  Pass in the values of globals insted of eval()ing their
names.  The use of eval() was obscure and unnecessary, and the patch
claimed random.py couldn't be used in Jython applets because of it.
2001-11-25 21:12:43 +00:00
Tim Peters
0e6d213177 Whitespace normalization. 2001-02-15 23:56:39 +00:00
Skip Montanaro
0de65807e6 bunch more __all__ lists
also modified check_all function to suppress all warnings since they aren't
relevant to what this test is doing (allows quiet checking of regsub, for
instance)
2001-02-15 22:15:14 +00:00
Tim Peters
bcd725fc45 Repaired a docstring. 2001-02-01 10:06:53 +00:00
Tim Peters
0de88fc4b1 Change random.seed() so that it can get at the full range of possible
internal states.  Put the old .seed() (which could only get at about
the square root of the # of possibilities) under the new name .whseed(),
for bit-level compatibility with older versions.  This occurred to me
while reviewing effbot's book (he found himself stumbling over .seed()
more than once there ...).
2001-02-01 04:59:18 +00:00
Tim Peters
715c4c412b New comment block to Clarify a subtlety. 2001-01-26 22:56:56 +00:00
Tim Peters
e360d9507a The combo of getstate/setstate/jumpahead is very powerful, but needs
examples to flesh it out for the uninitiated.  Here they are.
2001-01-26 10:00:39 +00:00
Tim Peters
85e2e4742d SF bug 130030: Claim of bad betavariate algorithm. 2001-01-26 06:49:56 +00:00
Tim Peters
cd80410854 Cosmetic changes after some sleep; no change in semantics. 2001-01-25 20:25:57 +00:00
Tim Peters
d52269bfd0 Fix bugs introduced by rewrite (in particular, time-based initialization
got broken).  Also added new method .jumpahead(N).  This finally gives us
a semi-decent answer to how Python's RNGs can be used safely and efficiently
in multithreaded programs (although it requires the user to use the new
machinery!).
2001-01-25 06:23:18 +00:00
Tim Peters
d7b5e88e8e Reworked random.py so that it no longer depends on, and offers all the
functionality of, whrandom.py.  Also closes all the "XXX" todos in
random.py.  New frequently-requested functions/methods getstate() and
setstate().  All exported functions are now bound methods of a hidden
instance.  Killed all unintended exports.  Updated the docs.
FRED:  The more I fiddle the docs, the less I understand the exact
intended use of the \var, \code, \method tags.  Please review critically.
GUIDO:  See email.  I updated NEWS as if whrandom were deprecated; I
think it should be.
2001-01-25 03:36:26 +00:00
Tim Peters
0c9886d589 Whitespace normalization. 2001-01-15 01:18:21 +00:00
Tim Peters
c1d65c34cf Repair senseless random.seed docstring (reported on c.l.py). 2000-09-16 04:02:48 +00:00
Guido van Rossum
e7b146fb3b The third and final doc-string sweep by Ka-Ping Yee.
The attached patches update the standard library so that all modules
have docstrings beginning with one-line summaries.

A new docstring was added to formatter.  The docstring for os.py
was updated to mention nt, os2, ce in addition to posix, dos, mac.
2000-02-04 15:28:42 +00:00
Guido van Rossum
6c395ba316 Add Tim Peters' shuffle() algorithm. 1999-08-18 13:53:28 +00:00
Guido van Rossum
3357561476 Added randrange to list of exported functions. 1998-07-31 13:40:05 +00:00
Guido van Rossum
d03e1197cb Make gauss() semi-thread-safe. It can still give duplicate results,
but it can no longer raise an exception when called by several threads
simultaneously.
1998-05-29 17:51:31 +00:00
Guido van Rossum
33d7f1a76c Add Interfaces to replace remaining needs for importing whrandom.
# XXX TO DO: make the distribution functions below into methods.
1998-05-20 16:28:24 +00:00