Python Speed Test

参照 Python 代码性能优化技巧 文章测试python提速。

• 优化前的代码（01.flow-a.py ）

  from time import time 
  t = time() 
  lista = [1,2,3,4,5,6,7,8,9,10] 
  listb =[0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,0.01] 
  for i in range (1000000): 
  for a in range(len(lista)): 
      for b in range(len(listb)): 
          x=lista[a]+listb[b] 
  print "total run time:"
  print time()-t
  

  [wuxiaomeng@WudeMacBook-Pro ~/Desktop/python/01.speedup ]
  $python 01.flow-a.py 
  total run time:
  21.2082309723
  

• 参照原文优化后（01.flow-b.py）

  from time import time 
  t = time() 
  lista = [1,2,3,4,5,6,7,8,9,10] 
  listb =[0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,0.01] 
  len1=len(lista) 
  len2=len(listb) 
  for i in xrange (1000000): 
  for a in xrange(len1): 
      temp=lista[a] 
      for b in xrange(len2): 
          x=temp+listb[b] 
  print "total run time:"
  

  [wuxiaomeng@WudeMacBook-Pro ~/Desktop/python/01.speedup ]
  $python 01.flow-b.py 
  total run time:
  17.1609051228
  

• 使用列表解析优化后（01.flow-c.py）

  from time import time 
  t = time() 
  lista = [1,2,3,4,5,6,7,8,9,10] 
  listb =[0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,0.01] 
  len1=len(lista) 
  len2=len(listb) 
  for i in xrange (1000000): 
  x = [a+b for a in lista for b in listb]
  print "total run time:"
  

  [wuxiaomeng@WudeMacBook-Pro ~/Desktop/python/01.speedup ]
  $python 01.flow-c.py 
  total run time:
  12.3668849468