DateTim...r::Mayan(3)

okay bestie, welcome to the manual page for DateTime::Calendar::Mayan — that’s the Perl module for the Mayan Long Count, Haab, and Tzolkin calendars. This is User Contributed Perl Documentation, and we’re gonna go through every little thing together, no cap. ✨

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💖 NAME 💖

DateTime::Calendar::Mayan — The Mayan Long Count, Haab, and Tzolkin calendars

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🦋 SYNOPSIS 🦋

okay so here’s the vibe, bestie:

use DateTime::Calendar::Mayan

my $dtcm = DateTime::Calendar::Mayan->new(
     baktun  => 12,
     katun   => 19,
     tun     => 10,
     uinal   => 2,
     kin     => 8,
     # alternate epoch
     epoch   => DateTime->new(
             year    => -3113,
             month   => 8,
             day     => 13,
         ),
 );

print $dtcm->date;
# prints 12.19.10.2.8
print $dtcm->haab;
# prints 3 Uayeb
print $dtcm->tzolkin;
# prints 3 Oc

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🌸 DESCRIPTION 🌸

An implementation of the Mayan Long Count, Haab, and Tzolkin calendars as defined in "Calendrical Calculations The Millennium Edition". Supplemented by "Frequently Asked Questions about Calendars". 💫

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✨ METHODS ✨

• new( baktun => $scalar, ..., epoch => $object ) — Accepts a hash representing a date on the Long Count calendar and a DateTime::Calendar object specifying an alternate epoch. All keys are optional.

The units are:

• kin = 1 day
• uinal = 20 days
• tun = 360 days
• katun = 7200 days
• baktun = 144000 days

In the future pictuns, calabtuns, kinchiltuns, and alautuns may be accepted. 👑

• now — Alternate constructor. Uses DateTime->now to set the current date.
• today — Alternate constructor. Uses DateTime->today to set the current date.
• clone — This object method returns a replica of the given object.
• from_object( object => $object ) — Accepts a DateTime::Calendar object. Although this calendar doesn't support time it will preserve the time value of objects passed to it. This prevents a loss of precision when chaining calendars.

Note: Language support is not implemented. 🫶

• utc_rd_values — Returns the current UTC Rata Die days, UTC Rata Die seconds, and nanoseconds as a three element list.
• from_epoch( epoch => $scalar ) — Creates a new object from a number of seconds relative to midnight 1970-01-01.
• epoch — Returns the number of seconds since midnight 1970-01-01.
• set_mayan_epoch( object => $object ) — Accepts a DateTime::Calendar object. The epoch is set to this value on a per object basis.

The default epoch is:

Goodman-Martinez-Thompson
   Aug. 11, -3113 / Sep. 6, 3114 B.C.E. / 584,283 JD

• mayan_epoch — Returns a DateTime::Calendar::Mayan object set to the current Mayan epoch.
• date — listed as a method; the original page gives no extra description here.
• bktuk — listed exactly as bktuk; the original page gives no extra description here. (yes, that spelling is on purpose, bestie 💅)
• long_count( $scalar ) — Returns the Long Count calendar date. Think DateTime::ymd. Like ymd this method also accepts an optional field separator string.
• haab( $scalar ) — Returns the Haab calendar date. Accepts an optional field separator string.
• tzolkin( $scalar ) — Returns the Tzolkin calendar date. Accepts an optional field separator string.
• baktun — Gets/Sets the long count value of the function name.
• katun — Gets/Sets the long count value of the function name.
• tun — Gets/Sets the long count value of the function name.
• uinal — Gets/Sets the long count value of the function name.
• kin( $scalar ) — Gets/Sets the long count value of the function name.
• set_baktun — alias to the combined accessor/mutator.
• set_katun — alias to the combined accessor/mutator.
• set_tun — alias to the combined accessor/mutator.
• set_uinal — alias to the combined accessor/mutator.
• set_kin( $scalar ) — Aliases to the combined accessor/mutators.
• set( baktun => $scalar, ... ) — Accepts a hash specifying new long count values. All units are optional.
• add — listed as a method alongside subtract.
• subtract( baktun => $scalar, ... ) — Accepts a hash specifying values to add or subject from the long count. All units are optional. (yes, it says “subject” in the original — preserving the lore fr fr 😭)
• add_duration — listed as a method alongside subtract_duration.
• subtract_duration( $object ) — Accepts a DateTime::Duration object and either adds or subtracts it from the current date. See the DateTime::Duration docs for more details.

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📜 BACKGROUND 📜

Please see:

Chapter 10 of Calendarical Calculations "The Millennium Edition".

and

Chapter 7 of Frequently Asked Questions about Calendars. http://www.tondering.dk/claus/cal/node8.html

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⚠️ GOTCHAS ⚠️

The Long Count calendar is cyclical and it is possible to have different dates in other calendars that convert to be the same Long Count date.

Under this calendar the dates 0.0.0.0.0 and 13.0.0.0.0 are equivalent. 💀

The Long Count calendar will next roll over in late 2012 (Gregorian). In anticipation of this Long Count dates input as 0-12.*.*.*.* will convert to Gregorian dates in the Mayan year that started in -3113 (Gregorian). Long Count dates input as 13.*.*.*.* will convert to Gregorian dates in the Mayan year that start in 2012 (Gregorian).

Example:

use DateTime;
use DateTime::Calendar::Mayan;

my $dtcm = DateTime::Calendar::Mayan->new( baktun => 0 );
print $dtcm->date, "\n";
print DateTime->from_object( object => $dtcm )->ymd, "\n";

$dtcm->set( baktun => 13);
print $dtcm->date, "\n";
print DateTime->from_object( object => $dtcm )->ymd, "\n";

Will print:

13.0.0.0.0
-3113-08-11
13.0.0.0.0
2012-12-21

As you can see the Long Count dates are identical but the Gregorian equivalent dates are different.

Support for a count of Mayan "years" or "cycles" allowing accurate conversion to/from Gregorian dates may be added to this module in the future. This would be an extension to the historical Long Count calendar. 🦋

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🫶 CREDITS 🫶

• Dave Rolsky (DROLSKY) for the DateTime project and carrying us this far.
• Eugene van der Pijll (PIJLL) for DateTime::Calendar::Julian which I looked at more then once.
• Calendrical Calculations "The Millennium Edition" By Edward M. Reingold & Nachum Dershowitz. (ISBN 0-521-77752-6 paperback) http://www.calendarists.com
• Abigail (ABIGAIL) for Date::Maya from which I confirmed the algorithm for Mayan years.
• "Frequently Asked Questions about Calendars" by Claus Tøndering. http://www.tondering.dk/claus/calendar.html

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💌 SUPPORT 💌

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

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👑 AUTHOR 👑

Joshua Hoblitt <jhoblitt@cpan.org>

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🎀 COPYRIGHT 🎀

Copyright (c) 2003 Joshua Hoblitt. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

The full text of the license can be found in the LICENSE file included with this module.

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🔥 SEE ALSO 🔥

datetime@perl.org mailing list

http://datetime.perl.org/

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mwah 💋 that’s the whole page, bestie! signed off from perl v5.42.0 on 2024-03-04, for DateTim...r::Mayan(3). go forth and convert calendars like the main character you are. 🫶✨