你如何减去日期时间对象？

Question

我试图从我的字典中找出两个转换后的时间字符串之间的区别。我已经使用 strptime() 将字符串从“历史值”转换为日期时间对象，但是当我从另一个中减去一个时，我得到了一个 TypeError。

from datetime import datetime


low_end_value = 50.00

stockDict = {'Historic value': [('16:00:00:00', 55.50), ("15:00:00:00", 45.50), 
("14:00:00:00", 75.50), ("13:00:00:00", 65.50), ("12:00:00:00", 55.50)]}

x = 0
while (stockDict['Historic value'][x][1]) > low_end_value:

   if (stockDict['Historic value'][x][1]) < low_end_value:
       break
   x += 1

date_str1 = (stockDict['Historic value'][(x - 1)][0])
# (n-1)th historical time

date_str2 = (stockDict['Historic value'][x][0])
# (n)th historical time

associated_time1 = (datetime.strptime(date_str1, '%H:%M:%S:%f').time())
# converted to a datetime object

associated_time2 = (datetime.strptime(date_str2, '%H:%M:%S:%f').time())
# converted to a datetime object

difference_in_time = associated_time1 - associated_time2

print(difference_in_time)

我收到的输出是：

Traceback (most recent call last):
 File "C:/Users/engli/PycharmProjects/Calculated time.py", line 47, in <module>
   difference_in_time = associated_time1 - associated_time2
TypeError: unsupported operand type(s) for -: 'datetime.time' and 'datetime.time'

最诚挚的问候，

安德鲁

Answer 1

尝试使用 datetime.combine() 方法。

from datetime import datetime, date
datetime.combine(date.min, associated_time1) - datetime.combine(date.min, associated_time2)