This notebook was prepared by Donne Martin. Source and license info is on GitHub.

Dates and Times

Basics
strftime
strptime
timedelta

Basics



In [1]:

    
from datetime import datetime, date, time



In [2]:

    
year = 2015
month = 1
day = 20
hour = 7
minute = 28
second = 15



In [3]:

    
dt = datetime(year, month, day, hour, minute, second)



In [4]:

    
dt.hour, dt.minute, dt.second









    Out[4]:





(7, 28, 15)

Extract the equivalent date object:



In [5]:

    
dt.date()









    Out[5]:





datetime.date(2015, 1, 20)

Extract the equivalent time object:



In [6]:

    
dt.time()









    Out[6]:





datetime.time(7, 28, 15)

When aggregating or grouping time series data, it is sometimes useful to replace fields of a series of datetimes such as zeroing out the minute and second fields:



In [7]:

    
dt.replace(minute=0, second=0)









    Out[7]:





datetime.datetime(2015, 1, 20, 7, 0)

strftime

Format a datetime string:



In [8]:

    
dt.strftime('%m/%d/%Y %H:%M')









    Out[8]:





'01/20/2015 07:28'

strptime

Convert a string into a datetime object:



In [9]:

    
datetime.strptime('20150120', '%Y%m%d')









    Out[9]:





datetime.datetime(2015, 1, 20, 0, 0)

timedelta

Get the current datetime:



In [10]:

    
dt_now = datetime.now()

Subtract two datetime fields to create a timedelta:



In [11]:

    
delta = dt_now - dt
delta









    Out[11]:





datetime.timedelta(6, 40171, 885211)

Add a datetime and a timedelta to get a new datetime:



In [12]:

    
dt + delta









    Out[12]:





datetime.datetime(2015, 1, 26, 18, 37, 46, 885211)