Python 将日期时间向下舍入到前一小时
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Round down datetime to previous hour
提问by DougKruger
How to round down datetime to previous hour? for example:
如何将日期时间舍入到前一小时？例如：
print datetime.now().replace(microsecond=0)
>> 2017-01-11 13:26:12.0
round down to previous hour: 2017-01-11 12:00:00.0
向下舍入到前一小时： 2017-01-11 12:00:00.0
回答by Willem Van Onsem
Given you want to round down to the hour, you can simply replace microsecond, secondand minutewith zeros:
鉴于您想四舍五入到 hour，您可以简单地替换microsecond,second并minute用零：
print(datetime.now().replace(microsecond=0, second=0, minute=0))
If you want to round down to the previoushour (as stated in the example 2017-01-11 13:26:12.0to 2017-01-11 12:00:00.0), replace microsecond, secondand minutewith zeros, then subtract one hour:
如果你想向下舍到先前的小时（如示例中陈述2017-01-11 13:26:12.0到2017-01-11 12:00:00.0），更换microsecond，second并minute用零，则减一小时：
from datetime import datetime, timedelta
print(datetime.now().replace(microsecond=0, second=0, minute=0) - timedelta(hours=1))
Example in the shell:
外壳中的示例：
$ python3
Python 3.5.2 (default, Nov 17 2016, 17:05:23)
[GCC 5.4.0 20160609] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from datetime import datetime, timedelta
>>> print(datetime.now().replace(microsecond=0, second=0, minute=0) - timedelta(hours=1))
2017-01-11 16:00:00
回答by gipsy
from datetime import datetime, timedelta
n = datetime.now() - timedelta(hours=1)
new_date = datetime(year=n.year, month=n.month, day=n.day, hour=n.hour)
