Newbie: Subtracting Dates

[Paul Rubin]

"mowestusa" <justnotworking at mail.com> writes:
> Basically, I would like to create a program that subtracts Date #1 from Date
> #2.  The output would give the total number of "years", "months", and "days"
> in between dates.  Like the following example:
> 
> Date #1    1/1/1900
> Date #2    12/6/2002
> Years:    102
> Months:  11
> Days:        5
> 
> If we are talking about antiques and Date #1 was the produced date.  The
> piece would be 102 years, 11 months, and 5 days.
> 
> Thanks for any direction.

Well, what does "102 years, 11 months, and 5 days" really mean?

For example, if date #1 is July 4, 1976 and date #2 is July 4, 1977,
what do you want the output to be?  Probably 1 year, 0 months, 0 days, ok?
The two dates are 365 days apart, so what else can you want?

Now what if date #1 is July 4, 1975 and date #2 is July 4, 1976?  This
time, because 1976 is a leap year, the dates are 366 days apart
instead of 365.  So is the answer still 1 year, 0 months, and 0 days,
in which case that answer doesn't always mean the same thing
(basically it's not in the same units as the quantities being
subtracted)?  Or is it 1 year, 0 months, and 1 day?  In that case your
1/1/1900 example isn't right, because of the 25 leap days in the
interval (1900 is not a leap year).

Maybe you want to just use the time.mktime function to convert both
dates into absolute time (seconds since epoch) and then subtract
arithmetically.