Python 实现的Binary Search 算法以及效率的对比

最近用Python3.2,3实现了一下Binary Search算法,同时看到网上有关于程序执行时间统计的代码段,于是就加到了程序里

import random
import functools
import timeit

original=[]
target=0;

def binary_search(target,seq=[],lowerindex=0,upperindex=None):
  "for binary search"
  middleIndex=int((upperindex+lowerindex)/2)
  if middleIndex==lowerindex:
    print("not found",target)
  else:
    if seq[middleIndex]==target:
      print("binary search found",seq[middleIndex])
      print("binary search index is:", middleIndex+1)
    elif seq[middleIndex]<target:
      binary_search(target,seq,middleIndex,upperindex)
    else:
      binary_search(target,seq,lowerindex,middleIndex)

def larget_number_search_binarysearch():
  print("target number is:",target);
  sortseq=original[:]
  sortseq.sort()
  binary_search(target,sortseq,0,len(sortseq));

def larget_number_search():
  for index,temp in enumerate(original):
      if target==temp:
        print("iterator search found", target);
        print("iterator index is:",index+1);
        break;

def compare_search_effective():
	"比较二分查找法与迭代查找法的效率"
  global original, target
  original=[random.randint(0,100000000) for x in range(1000000000)]
  target=random.choice(original);
  #通过timeit.Timer统计发放的执行时间
  binary_search_time = timeit.Timer('larget_number_search_binarysearch()',"from __main__ import larget_number_search_binarysearch") # v3
  iterator_search_time=timeit.Timer('larget_number_search()',"from __main__ import larget_number_search") # v3
  
  print ("binary search time:",binary_search_time.timeit(1),"\n");
  print ("iterator search time:",iterator_search_time.timeit(1));

#Main
if __name__=="__main__":
  compare_search_effective();