IDATE(1)							   User Commands							  IDATE(1)

NAME

       idate - A Gregorian/Meladi to/from Hijri/Islamic date converter

SYNOPSIS

       idate [--gregorian yyyymmdd] [--hijri yyyymmdd] [--simple] [--umm_alqura] [--help]

DESCRIPTION

       The  idate  program  is a Gregorian to Hijri (and vice-versa) date converter.  The application uses and offers multiple calculation methods
       with not all of them agreeing at all times.  The reason for this multiplicity is due to not having one agreed upon method  and  so  various
       entities develop and advocate their calculations.

       idate  is able to comprehend and calculate both pre-epoch or pre-Hijrah, denoted as "B.H", as well as post-epoch or post-Hijrah, denoted as
       "A.H", dates.  idate also utilizes Gregorian's pre-epoch "B.C" and post-epoch "A.D" dates and notes them per  its  output.   When  entering
       pre-epoch years, negative numbers ought to be utilized.

       idate when run without any command-line options uses the host machine's current Gregorian date and converts it to Hijri.

OPTIONS

       idate  follows  the  usual  GNU	command  line syntax, with long options starting with two dashes (`-').  A summary of all options is noted
       below:

       -h, --help
	      Show summary of options

       -g, --gregorian yyyymmdd
	      Specify the Gregorian date to be converted where 'y' stands for year, 'm' for month and 'd' for day

       -hi, --hijri yyyymmdd
	      Specify the Hijri date to be converted where 'y' stands for year, 'm' for month and 'd' for day

       -s, --simple
	      Specify a simplified output mode

       -u, --umm_alqura
	      Specify to use the Umm Al-Qura calculation method (used mostly in Saudi Arabia)

BACKGROUND

       The Hijri calendar is used in most of the Arab world and is the symbolic calendar of the Islamic faithed worldwide.  This calendar is known
       as  the	"Hijri"  (based  on the word "Hijrah" - denoting migration in Arabic) to signal Prophet Mohammed's (PBUH) migration from Makkah to
       Medinah on Thursday, July 15, 622 AD (Julian) or July 19, 622 AD (Gregorian).

       The Islamic Hijri calendar is strictly lunar (ie. moon-based) with twelve lunar months which do not correspond or track their  solar  coun-
       terparts  (the Gregorian calendar is a solar or sun-based calendar).  Lunar years and thus Hijri years are, on average, about 354 days long
       resulting in a Hijri year being roughly about 11 days shorter than its Gregorian counterpart.

       There is much discussion and confusion regarding how best to track the Hijri calendar.  A great deal of that confusion is based on the fact
       that  many rely on a human moon sighting to denote the start (or end) of a month (each month of the Hijri calendar starts when a new moon's
       crescent is observed or is made visible at sunset) as opposed to using an empirical mathematic certainty.  The methods  presented  in  this
       application  and  its  underlying  ITL  library are strictly arithmetic in nature and do NOT take moon-phases into consideration (in short,
       observational approximation is not used).

LIMITATIONS

       The Umm Al-Qura option doesn't function with pre-epoch settings.

REPORTING BUGS

       Report bugs on the web using http://bugs.arabeyes.org

AUTHOR

       Written by Nadim Shaikli as part of the Arabeyes.org project.

COPYRIGHT

       idate is subject to the GNU General Public License (GPL).
       Copyright (C) 2005, Arabeyes, Nadim Shaikli.

SEE ALSO

       The ITL library (libitl) from the Islamic Tools and Libraries project.  It is the underlying requirement for idate to  function.   The  ITL
       library was created and is hosted at www.arabeyes.org.

idate								 January 05, 2005							  IDATE(1)