Thetkarit

Overview

This project focuses on Burmese calendar calculations and astronomy studies and is still under active development.

Most of the code in this repository is in the public domain or released under an open source license. However, some code and/or data may use different copyright terms (usually still an open source license). See Resources.

Note: Variable-date holidays are handled in two ways: Thingyan and Myanmar New Year are calculated algorithmically, while holidays such as "Deepavali" and "Eid al-Adha" use maintained date tables.

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C++

Download the latest thetkarit.zip from https://github.com/phothinmg/thetkarit/releases/latest/download/thetkarit.zip.

#include "thetkarit/bcal.hpp" // include bcal header
#include <iostream>
#include <iomanip>

/// @brief Gregorian Calendar Date to Burmese Calendar Date
int main()
{
    bcal::BcalInfo dv = bcal::day_v(2025, 2, 12).bcal_info;
    std::cout << "Sasana Year: " << std::setprecision(0) << dv.sasana_year << std::endl;
    std::cout << "Burmese Year: " << std::setprecision(0) << dv.burmese_year << std::endl;
    std::cout << "Burmese Month: " << dv.burmese_month_str << std::endl;
    std::cout << "Moon Phase: " << dv.moon_phases_str << std::endl;
    std::cout << "Fortnight Day: " << std::setprecision(0) << dv.fortnight_day << std::endl;
    std::cout << "Day in Burmese Month: " << std::setprecision(0) << dv.burmese_day << std::endl;
    std::cout << "Public Holidays: ";
    for (const auto &holiday : dv.public_holiday)
    {
        std::cout << holiday << std::endl;
    }
}

```text
Sasana Year: 2568
Burmese Year: 1386
Burmese Month: Tabodwe
Moon Phase: Waxing
Fortnight Day: 12
Day in Burmese Month: 12
Public Holidays: Union Day

Build and Run the C++ Example

Clone the repository, build it with CMake, and run the example:

git clone https://github.com/phothinmg/thetkarit.git
cd thetkarit
mkdir build
cd build
cmake ..
make
./bcal # Run the example

---

Node.js

Install

npm install thetkarit

ESM (JavaScript)

import { BurmeseCal } from "thetkarit";

const cal = new BurmeseCal();
const day = cal.dayView({
  year: 2025,
  month: 2,
  day: 12,
  lang: "English",
});

console.log("Sasana Year:", day.burmese_cal.sasana_year.id);
console.log("Burmese Year:", day.burmese_cal.burmese_year.id);
console.log("Burmese Month:", day.burmese_cal.burmese_month.str);
console.log("Moon Phase:", day.burmese_cal.moon_phase.str);
console.log("Fortnight Day:", day.burmese_cal.fortnight_day.id);
console.log("Day in Burmese Month:", day.burmese_cal.burmese_day.id);
console.log("Public Holidays:", day.burmese_cal.public_holiday.join(", "));

TypeScript

import { BurmeseCal } from "thetkarit";

const cal = new BurmeseCal();
const day = cal.dayView({
  year: 2025,
  month: 2,
  day: 12,
  lang: "English",
});

console.log("Sasana Year:", day.burmese_cal.sasana_year.id);
console.log("Burmese Year:", day.burmese_cal.burmese_year.id);
console.log("Burmese Month:", day.burmese_cal.burmese_month.str);
console.log("Moon Phase:", day.burmese_cal.moon_phase.str);
console.log("Fortnight Day:", day.burmese_cal.fortnight_day.id);
console.log("Day in Burmese Month:", day.burmese_cal.burmese_day.id);
console.log("Public Holidays:", day.burmese_cal.public_holiday.join(", "));

CommonJS

const { BurmeseCal } = require("thetkarit");

const cal = new BurmeseCal();
const day = cal.dayView({
  year: 2025,
  month: 2,
  day: 12,
  lang: "English",
});

console.log("Sasana Year:", day.burmese_cal.sasana_year.id);
console.log("Burmese Year:", day.burmese_cal.burmese_year.id);
console.log("Burmese Month:", day.burmese_cal.burmese_month.str);
console.log("Moon Phase:", day.burmese_cal.moon_phase.str);
console.log("Fortnight Day:", day.burmese_cal.fortnight_day.id);
console.log("Day in Burmese Month:", day.burmese_cal.burmese_day.id);
console.log("Public Holidays:", day.burmese_cal.public_holiday.join(", "));

---

Resources

Burmese Calendar

• The algorithm for calculating the Burmese Calendar (Myanmar Calendar) and astrological calendar days by Dr. Yan Naing Aye.

• References:

  https://cool-emerald.blogspot.com/2013/06/algorithm-program-and-calculation-of.html

  https://cool-emerald.blogspot.com/2013/12/myanmar-astrological-calendar-days.html

Julian Date and Moon Phases

• A collection of astronomy-related programs, algorithms, tutorials, and data, including an implementation of the algorithm from Meeus' Astronomical Algorithms for computing the dates of the Moon's phases, by Greg Miller (gmiller@gregmiller.net).

• Reference: https://www.celestialprogramming.com/

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