Xref: utzoo comp.databases:6742 comp.software-eng:4036
Path: utzoo!attcan!uunet!cs.utexas.edu!sun-barr!newstop!sun!jasonf
From: jasonf@cetemp.Eng.Sun.COM (Jason Freund)
Newsgroups: comp.databases,comp.software-eng
Subject: Calendar Algorithm
Keywords: calendar algorithm
Message-ID: <140352@sun.Eng.Sun.COM>
Date: 8 Aug 90 16:12:23 GMT
Sender: news@sun.Eng.Sun.COM
Lines: 24


	I need to be able to change dates in a database cell with commands like
"+4w" == "Find the closest weekday to the day 4 weeks from a certain date", 
"-12d" == "Find the closest weekday 12 days earlier than this date.", and so 
on.  I'll be writing in Pascal -- the code is no problem -- I'll give my 
function a "+/-", a number, and a "d/w/m" (day, week, month), and a date 
"MMDDYY".  The function returns the closes weekday by adding/subtracting 
according to its parameters.  Does anyone know of a general algorithm for 
dealing with calendars?  It must that take into account leap years and be able 
to find what day of the week it is (MTWRF) so that it can make approximations 
to weekdays. I've seen some good ones before, (for computing how many days old 
you are and what day of the week you were born on) but I can't find any now.  

BTW, when is the next leap year?

Thanks,
Jason Freund, Sun Microsystems,  jasonf@cetemp.Corp.sun.com  <== summer address
Deprtmnt of Computer Science, Univ California, Davis. freund@sakura.ucdavis.edu
Quantum Link: JasonF5,  Compu$erve: 72007,244, 690 Erie Dr, Sunnyvale, CA 94087
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