Julian Day Numbers

David N. Smith (IBM) dnsmith at watson.ibm.com
Wed Apr 21 15:41:44 UTC 1999


At 11:45 -0400 4/16/99, J Chapman wrote:
>Does anyone have code that returns the Julian Day Number for a Gregorian
>date?

A good reference for any date computation (including Mayan, Persian, Hindu
and other obscure calendars) is the recent book:

   Calendrical Calculations, Dershowitz & Reingold,
   Cambridge University Press, 1997, 300 pp,
   ISBN 0-521-56474-3

It covers the full range of calendars and computations on them, provides
algorithms in a pseudocode and Lisp. Versions in Lisp, Mathematica, and
Java are available on the web. See:

   http://emr.cs.uiuc.edu/home/reingold/calendar-book/

This is quite a book and I certainly recommend it for anyone interested in
calendrical calculations. It sits firmly on my algorithm book shelf. (I
have no financial interest, etc.) The web site also has a large list of
pointers to other calendar sites.

BTW, the paper version costs about a third of the hardback version.

Dave
_______________________________
David N. Smith
IBM T J Watson Research Center
Hawthorne, NY
_______________________________
Any opinions or recommendations
herein are those of the author
and not of his employer.





More information about the Squeak-dev mailing list