1. Seeking someone smarter than me...

Hi All,

Does one of you college-type peoples happen to have the formula for
Zeller=92s Congruence Algorithm handy?  I need it very badly, but I can't
find it anywhere on the web, and my dog ate my old homework...

Brian

new topic     » topic index » view message » categorize

2. Re: Seeking someone smarter than me...

On Mon, 13 Dec 1999 16:27:56 -0500, Brian Jackson
<bjackson at 2FARGON.HYPERMART.NET> wrote:

>Hi All,
>
>Does one of you college-type peoples happen to have the formula for
>Zeller=92s Congruence Algorithm handy?  I need it very badly, but I can't
>find it anywhere on the web, and my dog ate my old homework...
>
>Brian

Never heard of it... but being a resourceful college-type I managed to
scrape up two different formulas:


D is the day of the month.
M is the month with March being 1 and January and February being months
11 and 12 of the previous year.
C is the century.
Y is the year.

d is the day of the week with Sunday as 0 and Saturday as 6.

d =3D ((26*M - 2)//10 + D + Y + Y//4 + C//4 - 2*C) mod 7

(// is integer division with truncation)

------------------------------------------------------

D =3D Day of the Month
M =3D Month
Y =3D Year (4 digits)

Day of Week =3D (D + 2M + [3/5(M + 1)] + Y + [Y / 4] - [Y/100] + 2) mod 7

where square brackets denote the greatest integer function. The greatest
integer function returns the largest integer that is less than or equal to
the argument. For example [2.3] =3D 2, [100] =3D 100, [3.14159] =3D 3. Mod 7=
 is
the remainder after dividing by 7. For example, 20 mod 7 =3D 6, 21 mod 7 =3D=
 0.

--------------------------------------------------------

I also found some examples in FORTRAN and C but I wouldn't want to pollute
the Eu List with them.  Junko has a Eu example at
http://www.rapideuphoria.com/daybdate.zip

new topic     » goto parent     » topic index » view message » categorize

3. Re: Seeking someone smarter than me...

On Mon, 13 Dec 1999 16:57:12 -0500, Brian Broker <bkb at CNW.COM> wrote:

>On Mon, 13 Dec 1999 16:27:56 -0500, Brian Jackson
><bjackson at 2FARGON.HYPERMART.NET> wrote:
>
>>Hi All,
>>
>>Does one of you college-type peoples happen to have the formula for
>>Zeller=92s Congruence Algorithm handy?  I need it very badly, but I can't
>>find it anywhere on the web, and my dog ate my old homework...
>>
>>Brian
>
>Never heard of it... but being a resourceful college-type I managed to
>scrape up two different formulas:
>
*** SNIP ***
>
>I also found some examples in FORTRAN and C but I wouldn't want to pollute
>the Eu List with them.  Junko has a Eu example at
>http://www.rapideuphoria.com/daybdate.zip

Thank you kindly. Even worse than FORTRAN, I have to write this in PL/B
(Databus) - YUK! (If you've never heard of it, you must be under 40!)

Brian

new topic     » goto parent     » topic index » view message » categorize

Search



Quick Links

User menu

Not signed in.

Misc Menu