def _check_date_fields(year, month, day):
year = _index(year)
month = _index(month)
day = _index(day)
if not MINYEAR <= year <= MAXYEAR:
raise ValueError('year must be in %d..%d' % (MINYEAR, MAXYEAR), year)
if not 1 <= month <= 12:
raise ValueError('month must be in 1..12', month)
dim = _days_in_month(year, month)
if not 1 <= day <= dim:
raise ValueError('day must be in 1..%d' % dim, day)
return year, month, day
def _check_time_fields(hour, minute, second, microsecond, fold):
hour = _index(hour)
minute = _index(minute)
second = _index(second)
microsecond = _index(microsecond)
if not 0 <= hour <= 23:
raise ValueError('hour must be in 0..23', hour)
if not 0 <= minute <= 59:
raise ValueError('minute must be in 0..59', minute)
if not 0 <= second <= 59:
raise ValueError('second must be in 0..59', second)
if not 0 <= microsecond <= 999999:
raise ValueError('microsecond must be in 0..999999', microsecond)
if fold not in (0, 1):
raise ValueError('fold must be either 0 or 1', fold)
return hour, minute, second, microsecond, fold
def randrange(self, start, stop=None, step=_ONE):
"""Choose a random item from range(stop) or range(start, stop[, step]).
Roughly equivalent to ``choice(range(start, stop, step))``
but supports arbitrarily large ranges and is optimized
for common cases.
"""
# This code is a bit messy to make it fast for the
# common case while still doing adequate error checking.
istart = _index(start)
if stop is None:
# We don't check for "step != 1" because it hasn't been
# type checked and converted to an integer yet.
if step is not _ONE:
raise TypeError('Missing a non-None stop argument')
if istart > 0:
return self._randbelow(istart)
raise ValueError("empty range for randrange()")
# Stop argument supplied.
istop = _index(stop)
width = istop - istart
istep = _index(step)
# Fast path.
if istep == 1:
if width > 0:
return istart + self._randbelow(width)
raise ValueError(f"empty range in randrange({start}, {stop}, {step})")
# Non-unit step argument supplied.
if istep > 0:
n = (width + istep - 1) // istep
elif istep < 0:
n = (width + istep + 1) // istep
else:
raise ValueError("zero step for randrange()")
if n <= 0:
raise ValueError(f"empty range in randrange({start}, {stop}, {step})")
return istart + istep * self._randbelow(n)
def binomialvariate(self, n=1, p=0.5):
"""Binomial random variable.
Gives the number of successes for *n* independent trials
with the probability of success in each trial being *p*:
sum(random() < p for i in range(n))
Returns an integer in the range: 0 <= X <= n
"""
# Error check inputs and handle edge cases
if n < 0:
raise ValueError("n must be non-negative")
if p <= 0.0 or p >= 1.0:
if p == 0.0:
return 0
if p == 1.0:
return n
raise ValueError("p must be in the range 0.0 <= p <= 1.0")
random = self.random
# Fast path for a common case
if n == 1:
return _index(random() < p)
# Exploit symmetry to establish: p <= 0.5
if p > 0.5:
return n - self.binomialvariate(n, 1.0 - p)
if n * p < 10.0:
# BG: Geometric method by Devroye with running time of O(np).
# https://dl.acm.org/doi/pdf/10.1145/42372.42381
x = y = 0
c = _log(1.0 - p)
if not c:
return x
while True:
y += _floor(_log(random()) / c) + 1
if y > n:
return x
x += 1
# BTRS: Transformed rejection with squeeze method by Wolfgang Hörmann
# https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.47.8407&rep=rep1&type=pdf
assert n * p >= 10.0 and p <= 0.5
setup_complete = False
spq = _sqrt(n * p *
(1.0 - p)) # Standard deviation of the distribution
b = 1.15 + 2.53 * spq
a = -0.0873 + 0.0248 * b + 0.01 * p
c = n * p + 0.5
vr = 0.92 - 4.2 / b
while True:
u = random()
v = random()
u -= 0.5
us = 0.5 - _fabs(u)
k = _floor((2.0 * a / us + b) * u + c)
if k < 0 or k > n:
continue
# The early-out "squeeze" test substantially reduces
# the number of acceptance condition evaluations.
if us >= 0.07 and v <= vr:
return k
# Acceptance-rejection test.
# Note, the original paper errorneously omits the call to log(v)
# when comparing to the log of the rescaled binomial distribution.
if not setup_complete:
alpha = (2.83 + 5.1 / b) * spq
lpq = _log(p / (1.0 - p))
m = _floor((n + 1) * p) # Mode of the distribution
h = _lgamma(m + 1) + _lgamma(n - m + 1)
setup_complete = True # Only needs to be done once
v *= alpha / (a / (us * us) + b)
if _log(v) <= h - _lgamma(k + 1) - _lgamma(n - k +
1) + (k - m) * lpq:
return k
def randrange(self, start, stop=None, step=_ONE):
"""Choose a random item from range(start, stop[, step]).
This fixes the problem with randint() which includes the
endpoint; in Python this is usually not what you want.
"""
# This code is a bit messy to make it fast for the
# common case while still doing adequate error checking.
try:
istart = _index(start)
except TypeError:
istart = int(start)
if istart != start:
_warn('randrange() will raise TypeError in the future',
DeprecationWarning, 2)
raise ValueError("non-integer arg 1 for randrange()")
_warn(
'non-integer arguments to randrange() have been deprecated '
'since Python 3.10 and will be removed in a subsequent '
'version', DeprecationWarning, 2)
if stop is None:
# We don't check for "step != 1" because it hasn't been
# type checked and converted to an integer yet.
if step is not _ONE:
raise TypeError('Missing a non-None stop argument')
if istart > 0:
return self._randbelow(istart)
raise ValueError("empty range for randrange()")
# stop argument supplied.
try:
istop = _index(stop)
except TypeError:
istop = int(stop)
if istop != stop:
_warn('randrange() will raise TypeError in the future',
DeprecationWarning, 2)
raise ValueError("non-integer stop for randrange()")
_warn(
'non-integer arguments to randrange() have been deprecated '
'since Python 3.10 and will be removed in a subsequent '
'version', DeprecationWarning, 2)
width = istop - istart
try:
istep = _index(step)
except TypeError:
istep = int(step)
if istep != step:
_warn('randrange() will raise TypeError in the future',
DeprecationWarning, 2)
raise ValueError("non-integer step for randrange()")
_warn(
'non-integer arguments to randrange() have been deprecated '
'since Python 3.10 and will be removed in a subsequent '
'version', DeprecationWarning, 2)
# Fast path.
if istep == 1:
if width > 0:
return istart + self._randbelow(width)
raise ValueError("empty range for randrange() (%d, %d, %d)" %
(istart, istop, width))
# Non-unit step argument supplied.
if istep > 0:
n = (width + istep - 1) // istep
elif istep < 0:
n = (width + istep + 1) // istep
else:
raise ValueError("zero step for randrange()")
if n <= 0:
raise ValueError("empty range for randrange()")
return istart + istep * self._randbelow(n)
def randrange(self, start, stop=None, step=1):
"""Choose a random item from range(start, stop[, step]).
This fixes the problem with randint() which includes the
endpoint; in Python this is usually not what you want.
"""
# This code is a bit messy to make it fast for the
# common case while still doing adequate error checking.
try:
istart = _index(start)
except TypeError:
if int(start) == start:
istart = int(start)
_warn(
'Float arguments to randrange() have been deprecated\n'
'since Python 3.10 and will be removed in a subsequent '
'version.', DeprecationWarning, 2)
else:
_warn('randrange() will raise TypeError in the future',
DeprecationWarning, 2)
raise ValueError("non-integer arg 1 for randrange()")
if stop is None:
if istart > 0:
return self._randbelow(istart)
raise ValueError("empty range for randrange()")
# stop argument supplied.
try:
istop = _index(stop)
except TypeError:
if int(stop) == stop:
istop = int(stop)
_warn(
'Float arguments to randrange() have been deprecated\n'
'since Python 3.10 and will be removed in a subsequent '
'version.', DeprecationWarning, 2)
else:
_warn('randrange() will raise TypeError in the future',
DeprecationWarning, 2)
raise ValueError("non-integer stop for randrange()")
try:
istep = _index(step)
except TypeError:
if int(step) == step:
istep = int(step)
_warn(
'Float arguments to randrange() have been deprecated\n'
'since Python 3.10 and will be removed in a subsequent '
'version.', DeprecationWarning, 2)
else:
_warn('randrange() will raise TypeError in the future',
DeprecationWarning, 2)
raise ValueError("non-integer step for randrange()")
width = istop - istart
if istep == 1 and width > 0:
return istart + self._randbelow(width)
if istep == 1:
raise ValueError("empty range for randrange() (%d, %d, %d)" %
(istart, istop, width))
# Non-unit step argument supplied.
if istep > 0:
n = (width + istep - 1) // istep
elif istep < 0:
n = (width + istep + 1) // istep
else:
raise ValueError("zero step for randrange()")
if n <= 0:
raise ValueError("empty range for randrange()")
return istart + istep * self._randbelow(n)
