timeit模块
timeit模块可以用来测试一小段Python代码的执行速度。
class timeit.Timer(stmt='pass', setup='pass', timer=<timer function>)
Timer是测量小段代码执行速度的类。
stmt参数是要测试的代码语句(statment);
setup参数是运行代码时需要的设置;
timer参数是一个定时器函数,与平台有关。
timeit.Timer.timeit(number=1000000)
timeit模块可以用来测试一小段Python代码的执行速度。
class timeit.Timer(stmt='pass', setup='pass', timer=<timer function>)
Timer是测量小段代码执行速度的类。
stmt参数是要测试的代码语句(statment);
setup参数是运行代码时需要的设置;
timer参数是一个定时器函数,与平台有关。
timeit.Timer.timeit(number=1000000)
Timer类中测试语句执行速度的对象方法。number参数是测试代码时的测试次数,默认为1000000次。方法返回执行代码的平均耗时,一个float类型的秒数。
list操作测试:
def test1(): l = [] for i in range(10000): l = l + [i] def test2(): l = [] for i in range(10000): l.append(i) def test3(): l = [i for i in range(10000)] def test4(): l = list(range(10000)) def test5(): l = [] for i in range(10000): l.extend([i]) from timeit import Timer t1 = Timer("test1()", "from __main__ import test1") print("concat ",t1.timeit(number=1000), "seconds") t2 = Timer("test2()", "from __main__ import test2") print("append ",t2.timeit(number=1000), "seconds") t3 = Timer("test3()", "from __main__ import test3") print("comprehension ",t3.timeit(number=1000), "seconds") t4 = Timer("test4()", "from __main__ import test4") print("list range ",t4.timeit(number=1000), "seconds") t5 = Timer("test5()", "from __main__ import test5") print("list extend ",t5.timeit(number=1000), "seconds")
测试结果:
concat 311.12743681273 seconds append 1.3331949470710924 seconds comprehension 0.6125603750695632 seconds list range 0.3800052549146926 seconds list extend 1.873306778224105 seconds