The seconds problem - redefined

[J. Landman Gay]

On 4/14/04 10:39 PM, SimPLsol at aol.com wrote:

>      Since I raised this topic I've gotten a LOT of good advice. 
> Unfortunately most of it does not address the problem. Apparently I have not defined it 
> well, please bear with me and I'll try again:
>      Start with a list of events: employee birthdays, anniversaries, start 
> dates, order due out dates, raw material due in dates, conferences, training 
> sessions, etc. The list is dynamic; new employees are hired, new materials are 
> purchased, materials scheduled previously arrive, etc.
>      Which events in that list will be happening, by day, for the next x 
> days?
>      For simplicity assume there are only three items in the event list; the 
> first event occurs on April 3rd 2004, the second on April 4th, and the third 
> on April 5th.
>      Revolution converts each date in the event list to seconds as follows:
>           April 3, 2004 - converts to 1080986400 seconds (OK)
>           April 4, 2004 - converts to 1081069200 seconds (will be a problem)
>           April 5, 2004 - converts to 1081155600 seconds (also a problem, 
> because of the 4th)
>      Next create a day by day calendar showing events from the event list 
> above for each calendar day. Start on April 2nd (1080900000 seconds) and review 
> four days, adding 86400 to get the comparison seconds for the next day to be 
> reviewed:
>           April 2, 2004 = 1080900000 seconds, 
>                empty (correct, no events in the event list above match this 
> date)
>           April 3, 2004 = 1080986400 seconds (1080900000 + 86400)
>                one event (correct, matches the April 3 seconds from the event 
> list above)
>           April 4, 2004 = 1081072800 seconds (1080986400 + 86400)
>                no match, (wrong, April 4 in the list above is short 3600 
> seconds, because April 3                only had 23 hours according to Revolution)
>           April 5, 2004 = 1081159200 seconds (1081072800 + 86400)
>                no match (wrong, April 5 in the list above is also short 3600 
> seconds,
>                indeed all dates until the 25 hour day in the autumn will not 
> match)
> 
>      If our review had started on the 4th (after the 23 hour day), all dates 
> would have matched correctly (until the 25 hour day in autumn).
> 
>      Hope that helps. Now back to the original question. Is there a way to 
> convert dates to seconds where every day has 86400 seconds?

Maybe I'm still not understanding correctly, but do you have to use 
seconds? Why not just convert a date to short date, or dateItems, or any 
other date format and compare that?

If you use dateItems, you can add 1 to the day item, reconvert, and get 
the correct date. For example, starting on April 2:

put "4/2/04" into theDate
-- scan your event list here, converting each one to short date.
-- compare and extract matches
convert theDate to dateItems
add 1 to item 3 of theDate
convert theDate to short date -- now it says "4/3/04"
-- scan the event list again and extract matches

etc.

If you add 1 to the days item when the date is April 30, the conversion 
from dateItems to any other date format will kick it over into May 
automatically. It's pretty easy.

-- 
Jacqueline Landman Gay         |     jacque at hyperactivesw.com
HyperActive Software           |     http://www.hyperactivesw.com