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#!/usr/bin/env python3
#
# Determine threshold for switching from longobject.c divmod to
# _pylong.int_divmod().
from random import randrange
from time import perf_counter as now
from _pylong import int_divmod as divmod_fast
BITS_PER_DIGIT = 30
def rand_digits(n):
top = 1 << (n * BITS_PER_DIGIT)
return randrange(top >> 1, top)
def probe_den(nd):
den = rand_digits(nd)
count = 0
for nn in range(nd, nd + 3000):
num = rand_digits(nn)
t0 = now()
e1, e2 = divmod(num, den)
t1 = now()
f1, f2 = divmod_fast(num, den)
t2 = now()
s1 = t1 - t0
s2 = t2 - t1
assert e1 == f1
assert e2 == f2
if s2 < s1:
count += 1
if count >= 3:
print(
"for",
nd,
"denom digits,",
nn - nd,
"extra num digits is enough",
)
break
else:
count = 0
else:
print("for", nd, "denom digits, no num seems big enough")
def main():
for nd in range(30):
nd = (nd + 1) * 100
probe_den(nd)
if __name__ == '__main__':
main()
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