Question

now I have datetime like mintt

In [134]: mintt
Out[134]: datetime.datetime(2012, 5, 9, 23, 21, 10, 548382, tzinfo=<matplotlib.dates._UTC object at 0x2f805d0>)    

and I change it like this:

In [131]: mintt.isoformat(" ").split(".")[0]
Out[131]: '2012-05-09 23:21:10'

how can I delete the minute and seconds,let it become “2012-05-09 23:00:00” ?

PS:at the beginning I use method below:

In [135]: mintt.strftime('%Y-%m-%d %H:00:00')
Out[135]: '2012-05-09 23:00:00'

but it will raise an exception like’ year=1601 is before 1900; the datetime strftime() methods require year >= 1900′

so I use isoformat method

Answer 1

Use the datetime.replace() method.

>>> import datetime
>>> t = datetime.datetime(2012, 5, 9, 23, 21, 10, 548382)
>>> t.replace(minute=0, second=0, microsecond=0).isoformat(' ')
'2012-05-09 23:00:00'

This doesn’t change t, it creates a new object.

>>> t
datetime.datetime(2012, 5, 9, 23, 21, 10, 548382) # still has same value