Python while、for、生成器、列表推导等语句的执行效率测试

import time,sys 
reps = 1000                #测试重复次数 
nums = 200000              #测试时数字大小 
 
 
def tester(func,*args):    #总体测试函数 
    startTime = time.time() 
    for i in range(reps): 
        func(*args) 
    elapsed = time.time() - startTime #用time模块来测试，结束时间与开始时间差 
    return elapsed 
 
def while_Statement():     #while循环实现 
    res = [] 
    x   = 0 
    while nums > x: 
        x += 1 
        res.append(abs(x)) 
 
def for_Statement():       #for循环实现 
    res = [] 
    for x in range(nums): 
        res.append(abs(x)) 
 
def generator_Expression():#生成器实现 
    res = list(abs(x) for x in range(nums)) 
 
def list_Comprehension():  #列表解析实现 
    res = [abs(x) for x in range(nums)] 
 
 
def map_Function():        #内置函数map实现 
    res = map(abs, range(nums)) 
 
 
print sys.version          #打印系统版本 
tests = [while_Statement, for_Statement, generator_Expression, list_Comprehension, map_Function] 
for testfunc in tests:     #将待测函数放置列表中依次遍历 
    print testfunc.__name__.ljust(20),': ',tester(testfunc)  # 
 

>>>  
2.7.4 (default, Apr  6 2013, 19:55:15) [MSC v.1500 64 bit (AMD64)] 
while_Statement      :  84.5769999027 
for_Statement        :  75.2709999084 
generator_Expression :  62.3519999981 
list_Comprehension   :  60.4090001583 
map_Function         :  47.5629999638 

import sys 
nums = 100 
 
def while_Statement(): 
    res = [] 
    x   = 0 
    while nums > x: 
        x += 1 
        res.append(abs(x)) 
 
def for_Statement(): 
    res = [] 
    for x in range(nums): 
        res.append(abs(x)) 
 
def generator_Expression(): 
    res = list(abs(x) for x in range(nums)) 
 
def list_Comprehension(): 
    res = [abs(x) for x in range(nums)] 
 
 
def map_Function(): 
    res = map(abs, range(nums)) 
 
if __name__=='__main__': 
    import timeit            #用timeit模块来测试 
    print sys.version 
    funcs = [while_Statement, for_Statement, generator_Expression, list_Comprehension, map_Function] 
    for func in funcs: 
        print func.__name__.ljust(20),': ',timeit.timeit("func()", setup="from __main__ import func") 

>>>  
2.7.4 (default, Apr  6 2013, 19:55:15) [MSC v.1500 64 bit (AMD64)] 
while_Statement      :  37.1800067428 
for_Statement        :  30.3999109329 
generator_Expression :  27.2597866441 
list_Comprehension   :  17.386223449 
map_Function         :  12.7386868963