Introdcution
Datetime module in Python supplies classes for date and time manipulation. Commonly used classes in the datetime module are:
- date Class
- time Class
- datetime Class
- timedelta Class
Below example gets the today’s date and time.
import datetime # Current Date and Time object = datetime.datetime.now() # Today's Date date = datetime.date.today()
Date Class
A date object represents a date (year, month and day). We can also create date objects from a timestamp. A Unix timestamp is the number of seconds between a particular date and January 1, 1970 at UTC.
from datetime import date
# Date object, Year, Month, Date
d = datetime.date(2019, 4, 13)
# Today's Date
today = date.today()
# Date from a timestamp
timestamp = date.fromtimestamp(1326244364)
# Today's year, month and day
print("Current year:", today.year)
print("Current month:", today.month)
print("Current day:", today.day)
# Modify values of date object
d = d.replace(month=10, day=13)Time class
A time object represents a time (hour, minute, second and microsecond). A time object instantiated from the time class represents the local time.
from datetime import time
# time(hour = 0, minute = 0, second = 0)
a = time()
# time(hour, minute and second)
b = time(11, 34, 56)
# time(hour, minute, second, microsecond)
d = time(11, 34, 56, 234566)
# Hour, minute, second and microsecond
print("hour =", a.hour)
print("minute =", a.minute)
print("second =", a.second)
print("microsecond =", a.microsecond)
# Modify values of time objects
a = a.replace(hour=5)Datetime class
A datetime object is a single object containing all the information from a date object and a time object. datetime module has a class named datetime that can contain information about both date and time.
from datetime import datetime
#datetime(year, month, day)
a = datetime(2018, 11, 28)
# datetime(year, month, day, hour, minute, second, microsecond)
b = datetime(2017, 11, 28, 23, 55, 59, 342380)
# year, month, hour, minute and timestamp
print("year =", a.year)
print("month =", a.month)
print("hour =", a.hour)
print("minute =", a.minute)
print("timestamp =", a.timestamp())
# Modify values of datetime objects
a = a.replace(year=2057, month=12)Timedelta class
A timedelta object represents the difference between two dates or times.
from datetime import timedelta
t1 = timedelta(weeks = 2, days = 5, hours = 1, seconds = 33)
t2 = timedelta(days = 4, hours = 11, minutes = 4, seconds = 54)
t3 = t1 - t2
# Duration in seconds
print("total seconds =", t3.total_seconds())
# Date manipulation
now = datetime.datetime.now()
oneyear = datetime.timedelta(days=365)
oneweek = datetime.timedelta(weeks=1)
print("One year from now : ", now + oneyear)
print("One week from now : ", now + oneweek)
print("One week ago was : ", now - oneweek)strftime()
This method is defined under classes date, datetime and time. It creates a formatted string from a given date, datetime or time object. The strftime() method takes one or more format codes and returns a formatted string based on it. Format codes are
- %Y – year [0001,…, 2018, 2019,…, 9999]
- %m – month [01, 02, …, 11, 12]
- %d – day [01, 02, …, 30, 31]
- %H – hour [00, 01, …, 22, 23
- %M – minute [00, 01, …, 58, 59]
- %S – second [00, 01, …, 58, 59]
from datetime import datetime
# Current date and time
now = datetime.now()
s1 = now.strftime("%H:%M:%S")
s2 = now.strftime("%m/%d/%Y, %H:%M:%S")
# Format day and month
print(now.strftime("%a, %A, %w, %e"))
print(now.strftime("%b, %B, %m"))
# Format time
print(now.strftime("%H, %I, %M, %S, %p"))
# Format short date format (m/d/y)
output = now.strftime("%m/%d/%y")
# Format long date format (Day, number, Month, Year)
output = now.strftime("%A %d, %B %Y")
# Format short date and time (m/d/y, H:M am/pm)
output = now.strftime("%m/%d/%y %I:%M %p")strptime()
The strptime() method creates a datetime object from a given string (representing date and time). The strptime() method takes two arguments:
- String representing date and time
- Format code equivalent to the first argument
from datetime import datetime
date_string = "21 June, 2018"
date_object = datetime.strptime(date_string, "%d %B, %Y")
print("date_object =", date_object)