* I pared down the answer. I'm not a big calendar calculating type of person, but I found the last paragraph confusing. I'm guessing that it's correct, but I don't think it really helps someone who doesn't know about calenders or Julian days already. I distilled David's suggestions into a couple of sentences.
* Instead of discussing julian days, I punted to an external discussion which seems clear and complete, and includes examples of calculations involving julian days. Index: perlfaq4.pod =================================================================== RCS file: /cvs/public/perlfaq/perlfaq4.pod,v retrieving revision 1.59 diff -u -d -r1.59 perlfaq4.pod --- perlfaq4.pod 19 Jan 2005 16:09:31 -0000 1.59 +++ perlfaq4.pod 31 Jan 2005 16:09:38 -0000 @@ -454,26 +454,17 @@ =head2 How can I find the Julian Day? -Use the Time::JulianDay module (part of the Time-modules bundle -available from CPAN.) +(contributed by brian d foy) -Before you immerse yourself too deeply in this, be sure to verify that -it is the I<Julian> Day you really want. Are you interested in a way -of getting serial days so that you just can tell how many days they -are apart or so that you can do also other date arithmetic? If you -are interested in performing date arithmetic, this can be done using -modules Date::Manip or Date::Calc. +You can use the Time::JulianDay module available on CPAN. Ensure that +you really want to find a Julian day, though, as many people have +different ideas about Julian days. See +http://www.hermetic.ch/cal_stud/jdn.htm for instance. -There is too many details and much confusion on this issue to cover in -this FAQ, but the term is applied (correctly) to a calendar now -supplanted by the Gregorian Calendar, with the Julian Calendar failing -to adjust properly for leap years on centennial years (among other -annoyances). The term is also used (incorrectly) to mean: [1] days in -the Gregorian Calendar; and [2] days since a particular starting time -or `epoch', usually 1970 in the Unix world and 1980 in the -MS-DOS/Windows world. If you find that it is not the first meaning -that you really want, then check out the Date::Manip and Date::Calc -modules. (Thanks to David Cassell for most of this text.) +If you need this for date arithmetic, you might also try the +Date::Manip or Date::Calc modules. If you want to calculate days +since a particular starting date, such as the unix epoch, you probably +want one of the Date::* modules. =head2 How do I find yesterday's date? -- brian d foy, [EMAIL PROTECTED]
