from datetime import datetime

now = datetime.now()

print(now.year,now.month,now.day)

#以毫秒形式存储时间

delta = now - datetime(1992,2,2)

print(delta)

print(delta.days)

#可以在时间戳上加减乘除

from datetime import timedelta

print(delta+timedelta(12))

#时间转str

time_str = now.strftime('%y-%m-%d')

print(time_str)

#str转时间

time_str2 = datetime.strptime(time_str,'%y-%m-%d')

print(time_str2)

#处理成组日期

data_set = ['2017-1-1','2018-1-1']

pd.to_datetime(data_set)

time_set = [datetime(2017,1,1),datetime(2017,2,1),datetime(2017,3,1),datetime(2017,4,1),datetime(2017,5,1)]

data = pd.DataFrame(np.arange(5),index=time_set)

data = pd.DataFrame(np.random.randn(1000),index=pd.date_range('1992-2-2',periods=1000))

#也可以做切片

data['1992-3-2':]