时间差

time_dl1 = pd.Timedelta(3,unit = 'h')
print(time_dl1)  # 输出结果: 0 days 03:00:00

time_dl2 = pd.Timedelta(3,unit = 'd')
print(time_dl2)  # 输出结果: 3 days 00:00:00

time_dl3 = pd.Timedelta(days = 7)
print(time_dl3)  # 输出结果: 7 days 00:00:00

date_range = pd.date_range('2021-12-21',periods=3,freq='D')
td = pd.Series([pd.Timedelta(days = i) for i in range(3,6)])
date_range1 = date_range + td
print(date_range1)

# 输出结果:
#  0   2021-12-24
#  1   2021-12-26
#  2   2021-12-28
#  dtype: datetime64[ns]