Yet-Another-Day-Of-Week A

 BBS: Inland Empire Archive
Date: 08-11-92 (09:08)             Number: 57
From: MONTE FERGUSON               Refer#: NONE
  To: ALL                           Recvd: NO  
Subj: Yet-Another-Day-Of-Week A      Conf: (2) Quik_Bas

 Here's one I picked out of a magazine (Creative
Computing?) many many moons ago... I think the equation is
called Zeller's Congruance or somesuch.

40 DEF FNYR(Y)=Y+(1900*ABS(Y<1582))
45 DEF FNDOWTEMP(M,D,Y)=_       (365*Y+D+31*(M-1)-
INT(.4*M+2.3)*(1-INT((60+(100/M))/100))+_
   INT((Y-INT((60+(100/M))/100))/4)-_
   INT(.75*(INT((Y-INT((60+(100/M))/100))/100+1))))
50 DEF FNDOW(M,D,Y)=FNDOWTEMP(M,D,FNYR(Y))-INT(FNDOWTEMP(M,D,FNYR(Y))/7)*7
55 DEF FNDAY$(M,D,Y)=MID$("SatSunMonTueWedThuFri",FNDOW(M,D,Y)*3+1,3)

 Forgive the formatting, I pulled this out of an ancient
BASICA program (blech).

 FNDOW(Month,Day,Year) returns 0 to 6 (0=Sat,
1=Sun...6=Fri). Year must be four digits. Example:
FNDOW(8,11,1992) returns 3 (Tuesday).

 FNDAY$(Month,Day,Year) returns a three-character string ("Sun", "Mon", etc).

 FNYR and FNDOWTEMP are used in FNDOW.

 Don't ask me how the equation works, I don't have a clue. But it does...




--- Cat 1.00
 * Origin: Chiba City Cat - Cleveland OH (1:157/200.39)