Detect If A Variable Is A Datetime Object

I have a variable and I need to know if it is a datetime object. So far I have been using the following hack in the function to detect datetime object: if 'datetime.datetime' in st

Solution 1:

You need isinstance(variable, datetime.datetime):

>>>import datetime>>>now = datetime.datetime.now()>>>isinstance(now, datetime.datetime)
True

Update

As noticed by Davos, datetime.datetime is a subclass of datetime.date, which means that the following would also work:

>>> isinstance(now, datetime.date)
True

Perhaps the best approach would be just testing the type (as suggested by Davos):

>>> type(now) is datetime.date
False>>> type(now) is datetime.datetime
True

Pandas Timestamp

One comment mentioned that in python3.7, that the original solution in this answer returns False (it works fine in python3.4). In that case, following Davos's comments, you could do following:

>>>type(now) is pandas.Timestamp

If you wanted to check whether an item was of type datetime.datetime OR pandas.Timestamp, just check for both

>>>(type(now) is datetime.datetime) or (type(now) is pandas.Timestamp)

Solution 2:

Use isinstance.

ifisinstance(variable,datetime.datetime):
    print"Yay!"

Solution 3:

Note, that datetime.date objects are not considered to be of datetime.datetime type, while datetime.datetime objects are considered to be of datetime.date type.

import datetime                                                                                                                     

today = datetime.date.today()                                                                                                       
now = datetime.datetime.now()                                                                                                       

isinstance(today, datetime.datetime)                                                                                                
>>> Falseisinstance(now, datetime.datetime)                                                                                                  
>>> Trueisinstance(now, datetime.date)                                                                                                      
>>> Trueisinstance(now, datetime.datetime)                                                                                                  
>>> True

Solution 4:

I believe all the above answer will work only if date is of type datetime.datetime. What if the date object is of type datetime.time or datetime.date?

This is how I find a datetime object. It always worked for me. (Python2 & Python3):

import datetime
type(date_obj) in (datetime, datetime.date, datetime.datetime, datetime.time)

Testing in Python2 or Python3 shell:

import datetime
d = datetime.datetime.now()  # creating a datetime.datetime object.
date = d.date()  # type(date): datetime.datetime = d.time()  # type(time): datetime.timetype(d) in (datetime, datetime.date, datetime.datetime, datetime.time)
True
type(date) in (datetime, datetime.date, datetime.datetime, datetime.time)
True
type(time) in (datetime, datetime.date, datetime.datetime, datetime.time)
True

Solution 5:

isinstance is your friend

>>>thing = "foo">>>isinstance(thing, str)
True