numpy使用

import numpy as np 
# 获取两个日期之间对应的日期，左闭右开区间
np.arange('2016-07-01', '2016-07-05', dtype='datetime64[D]')

#输出：
array(['2016-07-01', '2016-07-02', '2016-07-03', '2016-07-04'],
      dtype='datetime64[D]')

# 获取当前日期
np.datetime64('today', 'D')

#输出：
numpy.datetime64('2020-06-14')

# 日期相加减
yesterday = np.datetime64('2016-07-01', 'D') - np.timedelta64(1, 'D')
today     = np.datetime64('today', 'D')
tomorrow  = np.datetime64('today', 'D') + np.timedelta64(1, 'D')
print ("2016-07-01的Yesterday is " + str(yesterday))
print ("Today is " + str(today))
print ("Tomorrow is "+ str(tomorrow))

#输出：
2016-07-01的Yesterday is 2016-06-30
Today is 2020-06-14
Tomorrow is 2020-06-15