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The third and final doc-string sweep by Ka-Ping Yee.

Browse source 
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.
This commit is contained in:
Guido van Rossum 2000-02-04 15:28:42 +00:00
parent 54f22ed30b
commit e7b146fb3b
29 changed files with 891 additions and 778 deletions
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117
Lib/whrandom.py
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@ -1,54 +1,52 @@
# WICHMANN-HILL RANDOM NUMBER GENERATOR
#
# Wichmann, B. A. & Hill, I. D. (1982)
# Algorithm AS 183:
# An efficient and portable pseudo-random number generator
# Applied Statistics 31 (1982) 188-190
#
# see also:
# Correction to Algorithm AS 183
# Applied Statistics 33 (1984) 123
#
# McLeod, A. I. (1985)
# A remark on Algorithm AS 183
# Applied Statistics 34 (1985),198-200
#
#
# USE:
# whrandom.random() yields double precision random numbers
# uniformly distributed between 0 and 1.
#
# whrandom.seed(x, y, z) must be called before whrandom.random()
# to seed the generator
#
# There is also an interface to create multiple independent
# random generators, and to choose from other ranges.
"""Wichman-Hill random number generator.
Wichmann, B. A. & Hill, I. D. (1982)
Algorithm AS 183:
An efficient and portable pseudo-random number generator
Applied Statistics 31 (1982) 188-190
see also:
Correction to Algorithm AS 183
Applied Statistics 33 (1984) 123
McLeod, A. I. (1985)
A remark on Algorithm AS 183
Applied Statistics 34 (1985),198-200
# Translated by Guido van Rossum from C source provided by
# Adrian Baddeley.
USE:
whrandom.random() yields double precision random numbers
uniformly distributed between 0 and 1.
whrandom.seed(x, y, z) must be called before whrandom.random()
to seed the generator
There is also an interface to create multiple independent
random generators, and to choose from other ranges.
# Multi-threading note: the random number generator used here is not
# thread-safe; it is possible that nearly simultaneous calls in
# different theads return the same random value. To avoid this, you
# have to use a lock around all calls. (I didn't want to slow this
# down in the serial case by using a lock here.)
Translated by Guido van Rossum from C source provided by
Adrian Baddeley.
Multi-threading note: the random number generator used here is not
thread-safe; it is possible that nearly simultaneous calls in
different theads return the same random value. To avoid this, you
have to use a lock around all calls. (I didn't want to slow this
down in the serial case by using a lock here.)
"""
class whrandom:
#
# Initialize an instance.
# Without arguments, initialize from current time.
# With arguments (x, y, z), initialize from them.
#
def __init__(self, x = 0, y = 0, z = 0):
"""Initialize an instance.
Without arguments, initialize from current time.
With arguments (x, y, z), initialize from them."""
self.seed(x, y, z)
#
# Set the seed from (x, y, z).
# These must be integers in the range [0, 256).
#
def seed(self, x = 0, y = 0, z = 0):
"""Set the seed from (x, y, z).
These must be integers in the range [0, 256)."""
if not type(x) == type(y) == type(z) == type(0):
raise TypeError, 'seeds must be integers'
if not (0 <= x < 256 and 0 <= y < 256 and 0 <= z < 256):
@ -63,10 +61,9 @@ class whrandom:
t, z = divmod(t, 256)
# Zero is a poor seed, so substitute 1
self._seed = (x or 1, y or 1, z or 1)
#
# Get the next random number in the range [0.0, 1.0).
#
def random(self):
"""Get the next random number in the range [0.0, 1.0)."""
# This part is thread-unsafe:
# BEGIN CRITICAL SECTION
x, y, z = self._seed
@ -79,30 +76,25 @@ class whrandom:
# END CRITICAL SECTION
#
return (x/30269.0 + y/30307.0 + z/30323.0) % 1.0
#
# Get a random number in the range [a, b).
#
def uniform(self, a, b):
"""Get a random number in the range [a, b)."""
return a + (b-a) * self.random()
#
# Get a random integer in the range [a, b] including both end points.
# (Deprecated; use randrange below.)
#
def randint(self, a, b):
"""Get a random integer in the range [a, b] including both end points.
(Deprecated; use randrange below.)"""
return self.randrange(a, b+1)
#
# Choose a random element from a non-empty sequence.
#
def choice(self, seq):
"""Choose a random element from a non-empty sequence."""
return seq[int(self.random() * len(seq))]
#
# Choose a random item from range([start,] step[, stop]).
# This fixes the problem with randint() which includes the
# endpoint; in Python this is usually not what you want.
#
def randrange(self, start, stop=None, step=1,
# Do not supply the following arguments
int=int, default=None):
def randrange(self, start, stop=None, step=1, int=int, default=None):
"""Choose a random item from range([start,] step[, stop]).
This fixes the problem with randint() which includes the
endpoint; in Python this is usually not what you want.
Do not supply the 'int' and 'default' arguments."""
# This code is a bit messy to make it fast for the
# common case while still doing adequate error checking
istart = int(start)
@ -136,7 +128,6 @@ class whrandom:
# Initialize from the current time
#
_inst = whrandom()
seed = _inst.seed
random = _inst.random