@drewsonne/maya-dates

A library for interacting with and modifying both the Maya Long Count (LC) and Calendar Round (CR) dates.

Quickstart

npm install [-g] @drewsonne/maya-dates

const mayadates = require('@drewsonne/maya-dates');
// Long Count from Initial Series on east side of Stele E, Quirigua
let lc = new mayadates.factory.LongCountFactory().parse('9.17.0.0.0');
console.log(`${lc.buildFullDate()}`);

This should print 13 Ajaw 18 Kumk'u 9.17. 0. 0. 0.

Instructions

Most implementations will consist of creating a fullDate, and passing it to an operation.

Date Creation

Creating a fullDate can be done either by:

• using a factory class (LongCountFactory, CalendarRoundFactory, FullDateFactory) and calling its parse(raw_string) function, where raw_string is a LC, CR, or CR and LC combination encoded as a string. To specify missing values in a fullDate, using *. For example,

const mayadates = require('@drewsonne/maya-dates');

const wildcard = mayadates.wildcard;

const partial_lc = new mayadates.factory.LongCountFactory().parse('9.17.0.0.*');
const partial_cr = new mayadates.factory.CalendarRoundFactory().parse('13 Ajaw * Kumk\'u');
const partial_date = new mayadates.factory.FullDateFactory().parse('13 Ajaw * Kumk\'u 9.17.0.0.*');

console.log(`LC: ${partial_lc.kIn === wildcard}`);
console.log(`CR: ${partial_cr.haab.coeff === wildcard}`);
console.log(`Full Date: ${partial_date.lc.kIn === wildcard}`);

• passing explicit values into a model factory or class (getCalendarRound, LongCount, FullDate).

const mayadates = require('@drewsonne/maya-dates');

const calendarRound = mayadates.calendarRound.getCalendarRound(
    13, 'Ajaw',
    18,  mayadates.calendarRound.getHaabMonth('Kumk\'u')
);
const lc = mayadates.lc.LongCount(0, 0, 0, 17, 9);
const fullDate = new mayadates.FullDate(calendarRound, lc);

console.log(`${lc}`);
console.log(`${calendarRound}`);
console.log(`${fullDate}`);

Operations

Once a full date object has been created, you can either add an integer to a fullDate using shift(number), or filling in missing values in wildcards. The operations namespace provides operators to expand a fullDate with a wildcard into all possible values for dates matching that wildcard pattern.

Documentation

Full documentation and reference can be found at https://drewsonne.github.io/maya-dates/.