import copy
a = range(100000)
%timeit -n 10 copy.copy(a) # 运行10次 copy.copy(a)

%timeit -n 10 copy.deepcopy(a)
10 loops, best of 3: 1.55 ms per loop
10 loops, best of 3: 151 ms per loop

a = range(1000)
s = set(a)
d = dict((i,1) for i in a)
%timeit -n 10000 100 in d
%timeit -n 10000 100 in s
10000 loops, best of 3: 43.5 ns per loop
10000 loops, best of 3: 49.6 ns per loop

%timeit -n 100 a = (i for i in range(100000))
%timeit -n 100 b = [i for i in range(100000)]
100 loops, best of 3: 1.54 ms per loop
100 loops, best of 3: 4.56 ms per loop

%timeit -n 10 for x in (i for i in range(100000)): pass
%timeit -n 10 for x in [i for i in range(100000)]: pass

10 loops, best of 3: 6.51 ms per loop
10 loops, best of 3: 5.54 ms per loop

def yield_func(ls):
  for i in ls:
    yield i+1

def not_yield_func(ls):
  return [i+1 for i in ls]

ls = range(1000000)
%timeit -n 10 for i in yield_func(ls):pass

%timeit -n 10 for i in not_yield_func(ls):pass

10 loops, best of 3: 63.8 ms per loop
10 loops, best of 3: 62.9 ms per loop

a = range(10000)
size_a = len(a)
%timeit -n 1000 for i in a: k = len(a)
%timeit -n 1000 for i in a: k = size_a
1000 loops, best of 3: 569 µs per loop
1000 loops, best of 3: 256 µs per loop

a = range(2000) 
%timeit -n 100 [i for i in a if 10 < i < 20 or 1000 < i < 2000]
%timeit -n 100 [i for i in a if 1000 < i < 2000 or 100 < i < 20]   
%timeit -n 100 [i for i in a if i % 2 == 0 and i > 1900]
%timeit -n 100 [i for i in a if i > 1900 and i % 2 == 0]
100 loops, best of 3: 287 µs per loop
100 loops, best of 3: 214 µs per loop
100 loops, best of 3: 128 µs per loop
100 loops, best of 3: 56.1 µs per loop

In [1]: %%timeit
  ...: s = ''
  ...: for i in a:
  ...:     s += i
  ...:
10000 loops, best of 3: 59.8 µs per loop

In [2]: %%timeit
s = ''.join(a)
  ...:
100000 loops, best of 3: 11.8 µs per loop

s1, s2 = 'ax', 'bx'

%timeit -n 100000 'abc%s%s' % (s1, s2)
%timeit -n 100000 'abc{0}{1}'.format(s1, s2)
%timeit -n 100000 'abc' + s1 + s2
100000 loops, best of 3: 183 ns per loop
100000 loops, best of 3: 169 ns per loop
100000 loops, best of 3: 103 ns per loop

In [3]: %%timeit -n 10000
  a,b=1,2
  ....: c=a;a=b;b=c;
  ....:
10000 loops, best of 3: 172 ns per loop

In [4]: %%timeit -n 10000

a,b=1,2a,b=b,a
  ....:
10000 loops, best of 3: 86 ns per loop

a = range(10000)
%timeit -n 100 [i for i in a if i == True]
%timeit -n 100 [i for i in a if i is True]
100 loops, best of 3: 531 µs per loop
100 loops, best of 3: 362 µs per loop

x, y, z = 1,2,3

%timeit -n 1000000 if x < y < z:pass
%timeit -n 1000000 if x < y and y < z:pass

1000000 loops, best of 3: 101 ns per loop
1000000 loops, best of 3: 121 ns per loop

def while_1():
  n = 100000
  while 1:
    n -= 1
    if n <= 0: break

def while_true():
  n = 100000
  while True:
    n -= 1
    if n <= 0: break

m, n = 1000000, 1000000

%timeit -n 100 while_1()
%timeit -n 100 while_true()
100 loops, best of 3: 3.69 ms per loop
100 loops, best of 3: 5.61 ms per loop

%timeit -n 10000 c = pow(2,20)
%timeit -n 10000 c = 2**20

10000 loops, best of 3: 284 ns per loop
10000 loops, best of 3: 16.9 ns per loop

import cPickle
import pickle
a = range(10000)
%timeit -n 100 x = cPickle.dumps(a)
%timeit -n 100 x = pickle.dumps(a)
100 loops, best of 3: 1.58 ms per loop
100 loops, best of 3: 17 ms per loop

import json
import cPickle
a = range(10000)
s1 = str(a)
s2 = cPickle.dumps(a)
s3 = json.dumps(a)
%timeit -n 100 x = eval(s1)
%timeit -n 100 x = cPickle.loads(s2)
%timeit -n 100 x = json.loads(s3)
100 loops, best of 3: 16.8 ms per loop
100 loops, best of 3: 2.02 ms per loop
100 loops, best of 3: 798 µs per loop