[Noisebridge-discuss] Hacker's calendar

[Leif Ryge]

On 01/03/2012 02:32 AM, Wladyslaw Zbikowski wrote:
> Are you looking for a new, more enlightened calendar to replace the
> stodgy and patriarchal old Gregorian? Considering a 13-month lunar but
> can't stand the seasonal drift? There's never been a better time to
> switch to Maya. With a convenient 20 day month, plus easy designation
> of periods when the portals between the mortal realm and the
> Underworld dissolve, it's the calendar everyone's talking about.
>
> http://modernhacker.com/mcal
>
> After this year, you may never need another calendar again!

Nice! But...

You appear to be using the glyphs of the 20 day names from the 260-day 
Tzolk'in' cycle to represent both numerals and the 19 month names of the 
Haab' cycle, and you aren't taking into account that the pseudo-month of 
Wayeb' (when those underworld portals dissolve) is not 20 days long but 
instead only "five unlucky days" (18 months of 20 days each plus 5 days 
of Wayeb' == the 365-day "vague solar year" of Haab'). Also, you're 
making the easy mistake of conflating the eighteen 20-day months of the 
Haab' cycle with the eighteen 20-day months (winal) which make up a tun 
in the Long Count; they are totally unrelated (because there is not an 
extra 5-day period like Wayeb', a tun is actually only 360 days long). 
You're also counting from one all over the place; only the Tzolk'in' day 
number should start at one (and go up to 13), everywhere else should 
start at zero.

So, as far as I can tell, your converter does not produce valid outputs 
for any input. It says today is "13.20.20 Pop 15", but I'm pretty sure 
it's actually "4 Muluk 17 K'ank'in 12.19.19.0.9".

But, thanks for causing me to learn about Maya calendar(s), and 
inspiring me to write my own converter:
https://github.com/leif/mayacal/blob/master/mayacal.py

It converts unix seconds to and from full long count dates (including 
the Tzolk'in' and Haab' dates), and produces results which match up with 
various dates I checked it against on wikipedia.

I kind of want to make your hacker calendar use those glyphs correctly 
(along with Maya numerals and the glyphs for the Haab' months) so that 
it can display accurate full long count dates for upcoming events... but 
I'm not going to do that today. Maybe next trecena.

TLDR: At midnight on December 20, 2012, the 12th B'ak'tun will come to 
an end, meaning that the date will roll over from "3 Kawak 2 K'ank'in 
12.19.19.17.19" to "4 Ajaw 3 K'ank'in 13.0.0.0.0". Probably there will 
be some parties.

~leif