Question

If I have a hard coded date, how can I compare it to a date that is given by the user?

I want to eventually compare a persons birthday to see how old they are. Can someone point me in the right direction?

Answer 1

You’ll want to use Python’s standard library datetime module to parse and convert the “date given by the user” to a datetime.date instance and then subtract that from the current date, datetime.date.today(). For example:

>>> birthdate_str = raw_input('Enter your birthday (yyyy-mm-dd): ')
Enter your birthday (yyyy-mm-dd): 1981-08-04
>>> birthdatetime = datetime.datetime.strptime(birthdate_str, '%Y-%m-%d')
>>> birthdate = birthdatetime.date()  # convert from datetime to just date
>>> age = datetime.date.today() - birthdate
>>> age
datetime.timedelta(11397)

age is a datetime.timedelta instance, and the 11397 is their age in days (available directly via age.days).

To get their age in years, you could do something like this:

>>> int(age.days / 365.24)
31