3.12.2019 Python

#import math
#print(math.sin(3))

#from math import sin, cos, pi
#print(sin(3), pi)

#import math as m
#print(m.sin(3))

#from math import sin as f

#from math import *
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t = timeit.timeit('pi*2', 'from math import pi')
print(t)

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pi = 3.14

t = timeit.timeit('pi*2', 'from __main__ import pi')
print(t)

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import random

n_stog = 1000

random.sample(range(10), 3)

stog = [random.random() for _ in range(n_stog)]

igly = ([random.random() for _ in range(500)] + random.sample(stog, 500))

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>>> len(set(igly)) == len(set(stog))
True
>>> len(set(igly)) & len(set(stog))
1000
-----------------------------------------

import timeit

MAX_EXPONENT = 5

# define tests
TEST_IN = '''
fount = 0
for x in needles:
    if x in haystack:
        found += 1
'''

TEST_SETS = '''
len(needles & haystack)
'''

TEST_LISTS_F_LISTS = '''
len(set(needles)) & len(set(haystack))
'''

NUMBER = 100

# define setup

SETUP_LISTS = '''
import random
random.seed(81)

haystack = [random.random() for _ in range(1000)]

needles = ([random.random() for _ in range(500)] + random.sample(haystack, 500))
'''

SETUP_SETS = '''
import random
random.seed(81)

haystack = {random.random() for _ in range(1000)}

needles = ({random.random() for _ in range(500)} | set(random.sample(haystack, 500)))
'''

tests = [('in_lists', TEST_IN, SETUP_LISTS),
         ('in_sets', TEST_IN, SETUP_SETS),
         ('sets', TEST_SETS, SETUP_SETS),
         ('sets from lists', TEST_LISTS_F_LISTS, SETUP_LISTS),]


t = timeit.timeit(TEST_IN, setup=SETUP_LISTS, number=NUMBER)
print(t)