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Time::JulianDay(3)    User Contributed Perl Documentation   Time::JulianDay(3)

NAME
       Time::JulianDay -- Julian calendar manipulations

SYNOPSIS
	       use Time::JulianDay

	       $jd = julian_day($year, $month_1_to_12, $day)
	       $jd = local_julian_day($seconds_since_1970);
	       $jd = gm_julian_day($seconds_since_1970);
	       ($year, $month_1_to_12, $day) = inverse_julian_day($jd)
	       $dow = day_of_week($jd)

	       print (Sun,Mon,Tue,Wed,Thu,Fri,Sat)[$dow];

	       $seconds_since_jan_1_1970 = jd_secondslocal($jd,	$hour, $min, $sec)
	       $seconds_since_jan_1_1970 = jd_secondsgm($jd, $hour, $min, $sec)
	       $seconds_since_jan_1_1970 = jd_timelocal($sec,$min,$hours,$mday,$month_0_to_11,$year)
	       $seconds_since_jan_1_1970 = jd_timegm($sec,$min,$hours,$mday,$month_0_to_11,$year)

DESCRIPTION
       JulianDay is a package that manipulates dates as	number of days since
       some time a long	time ago.  It's	easy to	add and	subtract time using
       julian days...

       The day_of_week returned	by day_of_week() is 0 for Sunday, and 6	for
       Saturday	and everything else is in between.

ERRATA
       Time::JulianDay is not a	correct	implementation.	 There are two
       problems.  The first problem is that Time::JulianDay only works with
       integers.  Julian Day can be fractional to represent time within	a day.
       If you call inverse_julian_day()	with a non-integer time, it will often
       give you	an incorrect result.

       The second problem is that Julian Days start at noon rather than
       midnight.  The julian_day() function returns results that are too large
       by 0.5.

       What to do about	these problems is currently open for debate.  I'm
       tempted to leave	the current functions alone and	add a second set with
       more accurate behavior.

       There is	another	implementation in Astro::Time that may be more
       accurate.

GENESIS
       Written by David	Muir Sharnoff <cpan@dave.sharnoff.org> with help from
       previous	work by	Kurt Jaeger aka	PI
       <zrzr0111@helpdesk.rus.uni-stuttgart.de>
	    based on postings from: Ian	Miller <ian_m@cix.compulink.co.uk>;
       Gary Puckering <garyp%cognos.uucp@uunet.uu.net>	    based on Collected
       Algorithms of the ACM ?;	and the	unknown-to-me author of	Time::Local.

LICENSE
       Copyright (C) 1996-1999 David Muir Sharnoff.  License hereby granted
       for anyone to use, modify or redistribute this module at	their own
       risk.  Please feed useful changes back to cpan@dave.sharnoff.org.

perl v5.32.1			  2011-05-06		    Time::JulianDay(3)

NAME | SYNOPSIS | DESCRIPTION | ERRATA | GENESIS | LICENSE

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