当前位置 博文首页 > python 获取毫秒级时间问题的解决

    python 获取毫秒级时间问题的解决

    作者:正一番薯 时间:2021-04-30 17:43

    根据网上的一些说法,

    在python里获取ms级系统时间可以通过以下方式获取:

    import datetime
    print(datetime.datetime.now().microsecond)

    但通过以下代码测试,发现返回的并不是ms的值,而是us的值:

    import datetime 
    def getTime_ms():
        return (datetime.datetime.now().hour*3600 +\
                datetime.datetime.now().minute*60+\
                datetime.datetime.now().second )*1000+\
               datetime.datetime.now().microsecond/1000
     
    def timetime():
        t = getTime_ms()
        while getTime_ms() - t < 500:
            pass
        a = getTime_ms()
        print(t, a, a- t) 
      
    if __name__ == '__main__': 
        from timeit import timeit
        t = timeit('timetime()', 'from __main__ import timetime', number=1)
        print(t)

    打印结果

    (35460614, 35461114, 500) 0.499531984329

    上面实验不太直观,换一个直观点的:

    def timetime():
        t1 = datetime.datetime.now()
        while 1:
            t2 = datetime.datetime.now()
            if (t2 - t1).microseconds >= 1:
                print(t2,t2.microsecond,t1,t1.microsecond,(t2-t1).seconds)
                break 
     
    if __name__ == '__main__':
        from timeit import timeit
        t = timeit('timetime()', 'from __main__ import timetime', number=1)
        print(t)
        #print (datetime.datetime.now())

    输出

    (datetime.datetime(2019, 4, 3, 10, 6, 20, 461882), 461882, datetime.datetime(2019, 4, 3, 10, 6, 20, 461863), 461863, 0) 7.10487365723e-05

    def timetime():
        t1 = datetime.datetime.now()
        while 1:
            t2 = datetime.datetime.now()
            if (t2 - t1).microseconds >= 1000:
                print(t2,t2.microsecond,t1,t1.microsecond,(t2-t1).seconds)
                break 
     
    if __name__ == '__main__':
        from timeit import timeit
        t = timeit('timetime()', 'from __main__ import timetime', number=1)
        print(t)
        #print (datetime.datetime.now())

    输出

    (datetime.datetime(2019, 4, 3, 10, 13, 52, 76548), 76548, datetime.datetime(2019, 4, 3, 10, 13, 52, 75547), 75547, 0) 0.00104904174805

    补充:Python datetime去除毫秒 返回当前时间

    datetime模块返回当前时间

    import datetime
    if __name__ == '__main__':
        a = datetime.datetime.now().replace(microsecond=0)
        print(a, type(a))
    

    运算结果:

    2020-05-22 12:13:42 <class 'datetime.datetime'> Process finished with exit code 0

    以上为个人经验,希望能给大家一个参考,也希望大家多多支持站长博客。如有错误或未考虑完全的地方,望不吝赐教。

    js