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datetime::format::epoch::jd(3pm) [debian man page]

DateTime::Format::Epoch::JD(3pm)			User Contributed Perl Documentation			  DateTime::Format::Epoch::JD(3pm)

NAME

       DateTime::Format::Epoch::JD - Convert DateTimes to/from Julian Days

SYNOPSIS

	 use DateTime::Format::Epoch::JD;

	 my $dt = DateTime::Format::Epoch::JD->parse_datetime( 2453244.5 );
	  # 2004-08-27T00:00:00
	 DateTime::Format::Epoch::JD->format_datetime($dt);
	  # 2453244.5

	 my $formatter = DateTime::Format::Epoch::JD->new();
	 my $dt2 = $formatter->parse_datetime( 2453244.5 );
	  # 2004-08-27T00:00:00
	 $formatter->format_datetime($dt2);
	  # 2453244.5

DESCRIPTION

       This module can convert a DateTime object (or any object that can be converted to a DateTime object) to the Julian Day number. This is the
       number of days since noon U.T.C. on January 1, 4713 B.C. (Julian calendar).

       This time scale was originally proposed by John Herschel, and is often used in astronomical calculations.

       Similar modules are:

       o   DateTime::Format::Epoch::MJD

	   Implements the "modified Julian Day", starting at midnight U.T.C., November 17, 1858.  This number is always 2,400,000.5 lower than the
	   JD, and this count only uses five digits to specify a date between 1859 and about 2130.

       o   DateTime::Format::Epoch::RJD

	   Implements the "reduced Julian Day", starting at noon U.T.C., November 16, 1858.  This number is always 2,400,000 lower than the JD.

       o   DateTime::Format::Epoch::TJD

	   Implements the "truncated Julian Day", starting at midnight U.T.C., May 24, 1968.  This number is always 2,440,000,5 lower than the JD.
	   Actually, there is another version of the TJD, defined as JD modulo 10,000.	But that one is a bit harder to implement, so you'll have
	   to do with this version of TJD.  Or don't use TJD's at all.

       o   DateTime::Format::Epoch::RataDie

	   Implements the Rata Die count, starting at January 1, 1 (Gregorian).  This count is used by DateTime::Calendar programmers.

       o   DateTime::Format::Epoch::Lilian

	   Implements the Lilian count, named after Aloysius Lilian (a 16th century physician) and first used by IBM (a 19th century punched card
	   machine manufacturer).  This counts the number of days since the adoption of the Gregorian calendar.  Only days are counted, and
	   October 15, 1584 is day 1.

METHODS

       Most of the methods are the same as those in DateTime::Format::Epoch.  The only difference is the constructor.

       o   new()

	   Constructor of the formatter/parser object. It has no parameters.

SUPPORT

       Support for this module is provided via the datetime@perl.org email list. See http://lists.perl.org/ for more details.

AUTHOR

       Eugene van der Pijll <pijll@gmx.net>

COPYRIGHT

       Copyright (c) 2004 Eugene van der Pijll.  All rights reserved.  This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

SEE ALSO

       DateTime

       datetime@perl.org mailing list

perl v5.10.1							    2007-12-03					  DateTime::Format::Epoch::JD(3pm)

Check Out this Related Man Page

Template::Plugin::DateTime::Format(3pm) 		User Contributed Perl Documentation		   Template::Plugin::DateTime::Format(3pm)

NAME

       Template::Plugin::DateTime::Format - format DateTime objects from inside TT with "DateTime::Format"-style formatters

VERSION

       version 0.02

SYNOPSIS

	  [% USE f = DateTime::Format('DateTime::Format::Strptime', { pattern => "%T" }) %]
	  [% f.format(datetime_object) %]

DESCRIPTION

       Oftentimes, you have a DateTime object that you want to render in your template.  However, the default rendering (2008-01-01T01:23:45) is
       pretty ugly.  Formatting the DateTime with a DateTime::Format object is the usual solution, but there's usually not a nice place to put the
       formatting code.

       This plugin solves that problem.  You can create a formatter object from within TT and then use that object to format DateTime objects.

   CREATING AN OBJECT
       Creating a formatter instance is done in the usual TT way:

	 [% USE varname = DateTime::Format( ... args ... ) %]

       This creates a new formatter and calls it "varname".

       The constructor takes up to three arguments.  The first argument is the name of the formatter class.  It is required, and the named class
       must follow the DateTime::Format API.  An exception will be thrown if the class cannot be loaded.

       The second argument is a reference to pass to the formatter's constructor.  If it is an array reference, the array will be dereferenced
       before being passed to "new" as @_.  Otherwise, the single reference is passed to the constructor.

       The third argument is optional and is the rest of @_ to pass to "format_datetime" after the DateTime object.  I don't know if this is
       actually allowed by the API, but I figured it might come in handy.

   FORMATTING DATES
       Once you've created the object, invoke the "format" method with the DateTime object you'd like to format.  The result of "format_datetime"
       is returned.

METHODS

   new
       Called by TT to create a new formatter.

   format($datetime)
       Formats $datetime.

AUTHOR

       Jonathan Rockway "<jrockway@cpan.org>"

COPYRIGHT AND LICENSE

       Copyright (c) 2008 Jonathan Rockway.

       This module is free software.  You may redistribute it under the same terms as perl itself.

AUTHOR

       Jonathan Rockway <jrockway@cpan.org>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2010 by Jonathan Rockway.

       This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

perl v5.14.2							    2010-12-27				   Template::Plugin::DateTime::Format(3pm)
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