Python 常用技巧(待续)

1. 计算运行时间

• time module

import timestart = time.time()for i in range(10):    print(i)end = time.time()end-start

• timeit module

def test():    l = []    for i in range(1000):        l.append(i)import timeitt = timeit.Timer("test()", "from __main__ import test")# from __main__ import test1 imports the function test1 # from the __main__ namespace into the namespace that # timeit sets up for the timing experiment. print(t.timeit(number=1000), "milliseconds")

2. 修改文件名字

import os# 改变当前工作目录os.chdir('C:/Users/dingx/Documents/Python_tmp')# 获取当前文件夹下文件名files=os.listdir()for filename in files:    # 删除每个文件名的前三个字    newname = filename[3:]    # 改名字    os.rename(filename , newname)