Python-сообщество

from time import time
from random import randrange as ran

t1=time(); a=[y for y in [ran(10000) for x in xrange(1000000)] if (0 < y and y < 255)]; t2=time(); t=t2-t1
t -> 1.1498439311981201

t1=time(); a=[y for y in [ran(10000) for x in xrange(1000000)] if x in xrange(255)]; t2=time(); t=t2-t1
t -> 7.0377130508422852

t1=time(); a=[y for y in [ran(10000) for x in xrange(1000000)] if x in range(255)]; t2=time(); t=t2-t1
t -> 7.3918559551239014

# Кстати:
t1=time(); a=[y for y in [ran(10000) for x in xrange(1000000)] if (0 < y < 255)]; t2=time(); t=t2-t1
t -> 1.1148099899291992

import timeit


a = timeit.Timer('0 < x and x < 255', setup = 'x = 10')
b = timeit.Timer('x in xrange(255)', setup = 'x = 10')
c = timeit.Timer('x in range(255)', setup = 'x = 10')
d = timeit.Timer('0 < x < 255', setup = 'x = 10')


print(a.timeit())
print(b.timeit())
print(c.timeit())
print(d.timeit())

print(a.timeit())
0.0665690898895  # Примем за единицу = 1.0

print(b.timeit())
0.452644109726  # 6.7996

print(c.timeit())
1.93519306183  # 29.0704

print(d.timeit())
0.0768120288849  # 1.1538

b = timeit.Timer('x in xrange(255)', setup = 'x = 225')
print(b.timeit())
5.31649303436 # 79.8642

c = timeit.Timer('x in range(255)', setup = 'x = 225')
print(c.timeit())
5.74042701721 # 86.2326