On 4/8/07, Brian Schott <[EMAIL PROTECTED]> wrote:
In casual conversation we talk about how far apart
our birthdays are...
Perhaps this one is worth considering.
days=: 31 28 31 30 31 30 31 31 30 31 30 31
datediff=: 4 : 0
'm d'=. y-x
(12|m-d<0), d+(days{~12|2-~{.y)*d<0
)
Examples:
a=. 11 5 NB. Nov 5
b=. 1 19 NB. Jan 19
a datediff b
2 4 NB. 2 months 4 days from a to b
b datediff a
9 17 NB. 9 months 17 days from b to a
3 25 datediff 6 25
3 0 NB. 3 months from Mar 25 to the same date in June
Of course, there still remains the need to deal with leap
years properly, but I am too lazy to do that :)
Regards,
Boyko
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