On 13.11.2013 02:33, waldo kitty wrote:
actually, i have in some cases... let's ask this question and see what
your charts and routines return as the result... assuming your format
is DD.MM.YYYY...
Date1 := 01.01.2000
Date2 := 01.01.2000
should be 0 (zero), right?
then
Date1 := 01.01.2000
Date2 := 02.01.2000
should be 1 (one), right?
in this case, what i (and bart, too) wrote, we're not counting the
starting day but we are counting the ending day... this rule stays in
effect throughout the entire process... my head still aches from
rummaging about doing this... it was good exercise and one i remember
being given on a test many years back to determine one's coding
level... at that time, the code was being done in dBase II/III/IV ;)
i will have to dig deeper and see what is crossing things up for count
from 29.02.2000 to 28.02.2001... i see bart has posted a fix which i
have not yet had a chance to compare with my code or run thru the
tests i included in my posting...
the real question is this:
what do we count? the starting day, the ending day, both days or
neither day?
then we have another question:
is dayM in monthY a one month difference to dayM in monthX and
monthZ? monthX, monthY, monthZ are any three consecutive months
in linear order within one year or crossing two years
once the rules are chosen, then we have something to work with...
I'm just a hobbyist, never went to university to study computer science.
We don't need to invent the wheel again, because others have solutions
for that!
Perhaps its solved in " The Art of/Computer Programming/" from Donald E.
Knuth?
I don't have such books and i don't know if i'd have the chance to
understand such a book?!!
Yesterday i was running windows on this PC and tried MS Visual Studio
2008 Help.
That showed me ( -> DateDiff ) a Tutorial from a MS-India guy that
delivered code to calculate DateDiff.
I'm now running Linux but perhaps i reboot later to look again?
Bart delivered code that calculates 29.02.2000 to 28.02.2001 = 1 Year.
And that looks reasonable to me!
Bart wrote:
I would actually say that in this particular case the diff is 1 Year...
(11 M + (28 days in feb in a non-leapyear = 1M) = 12M = 1 Y.
Bart
Soon we'll have working DateDiff function and my question will be
answered in the end!
Thanks guys!!
--
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