Panchangam (Wasm)


> High-Precision Vedic Astrology & Calendar Library
>
> _Powered by Swiss Ephemeris | Compiled to WebAssembly | Built for the Edge_

🌟 Why Panchangam?

Most Vedic astrology libraries rely on static lookup tables or simplified
algorithms that trade accuracy for speed. Panchangam bridges the gap between
ancient Vedic requirements and modern astronomical precision.

1. Astronomical Precision ("Drik Ganita"): We wrap the industry-standard
Swiss Ephemeris (used by NASA/JPL) to calculate planetary positions to
millisecond precision. No approximations.
2. The "Udaya Tithi" Standard: In Vedic traditions, the day doesn't start at
midnight; it starts at Sunrise. We calculate exact local sunrise times
(taking atmospheric refraction and altitude into account) to determine the
correct Tithi, Nakshatra, and Yoga for any location on Earth.
3. Wasm-First Performance: Written in Rust and compiled to
WebAssembly, this library runs with near-native performance in
Node.js, Deno, and Cloudflare Workers. It's designed for
serverless scalability.

✨ Features

- Swiss Ephemeris v2.10.03: The gold standard for planetary calculations.
- Vedic Calendar (Panchang):
- Tithi: Lunar day (1-30) with precise start and end times.
- Nakshatra: 27 Lunar mansions with start and end times.
- Yoga: 27 Luni-solar combinations.
- Karana: 11 Half-Tithis.
- Vara: Weekday based on sunrise-to-sunrise logic.
- Advanced Astronomy:
- True Ayanamsa: Support for Lahiri (Chitrapaksha), Raman,
Krishnamurti, True Chitrapaksha, and more.
- Planetary Dignity: Automatic calculation of Exalted, Debilitated, Own
Sign, Friend/Enemy status.
- Planetary War (Graha Yuddha): Detects when planets are dangerously close
(< 1°).
- Extended Muhurat: Real-time calculation of:
- Rahu Kalam, Yamaganda, Gulika (8-part day division)
- Brahma Muhurta (Pre-dawn spiritual window)
- Abhijit Muhurta (Mid-day victory period)

🚀 Usage

$3

This project is currently distributed as a source crate. Verify and build the
Wasm bindings locally.

Prerequisites:

- Rust (stable)
- Deno (v1.37+)

One-Step Build:

``bash
deno task build
`

This generates:

- ./lib/panchangam.js: The ESM entry point.
- ./lib/panchangam.wasm: The compiled Wasm binary.
- ./lib/panchangam.d.ts: Fully typed TypeScript definitions.

$3

Calculate comprehensive Panchang data including precise end times.

`typescript
import { calculate_daily_panchang, Location } from "./lib/panchangam.js";

// 1. Define Location: New Delhi (28.61 N, 77.20 E, 225m)
const delhi = new Location(28.6139, 77.2090, 225.0);

// 2. Calculate for January 1, 2024
// params: (year, month, day, location, ayanamsha_mode)
// mode 1 = Lahiri (Standard)
const result = calculate_daily_panchang(2024, 1, 1, delhi, 1);

// 3. Output Results
console.log(Sunrise: ${new Date(result.sunrise).toLocaleTimeString()});
console.log(Tithi: ${result.tithi_name});
console.log( - Ends at: ${new Date(result.tithi_end_time).toLocaleString()});
console.log(Nakshatra: ${result.nakshatra_name});
console.log(
- Ends at: ${new Date(result.nakshatra_end_time).toLocaleString()},
);
`

$3

Get precise sidereal positions and dignity status for all planets.

`typescript
import { calculate_planets, swe_julday } from "./lib/panchangam.js";

// Julian Day for calculation
const jd = swe_julday(2024, 1, 1, 12.0, 1); // Noon UT

// Calculate Sidereal positions (Mode 1 = Lahiri)
const planets = calculate_planets(jd, 1);

planets.forEach((p) => {
console.log(${p.name}: ${p.longitude.toFixed(2)}°);
console.log( Dignity: ${p.dignity}); // Exalted, Own Sign, Friend, etc.
console.log( Speed: ${p.speed.toFixed(4)}/day);
if (p.is_retrograde) console.log(" [Retrograde]");
});
`

$3

Determine auspicious and inauspicious time windows.

`typescript
// Accessed via the daily panchang result
const muhurats = result.muhurats;

console.log("--- Inauspicious Periods ---");
console.log(
Rahu Kalam: ${new Date(muhurats.rahu_kalam.start).toLocaleTimeString()} - ${
new Date(muhurats.rahu_kalam.end).toLocaleTimeString()
},
);
console.log(
Yamaganda: ${new Date(muhurats.yamaganda.start).toLocaleTimeString()} - ${
new Date(muhurats.yamaganda.end).toLocaleTimeString()
},
);

console.log("--- Auspicious Periods ---");
console.log(
Brahma Muhurta: ${
new Date(muhurats.brahma_muhurta.start).toLocaleTimeString()
},
);
console.log(
Abhijit Muhurta: ${
new Date(muhurats.abhijit_muhurta.start).toLocaleTimeString()
},
);
`

$3

Detect planetary wars where planets are within 1° of each other.

`typescript
import { check_graha_yuddha, swe_julday } from "./lib/panchangam.js";

const jd = swe_julday(2024, 1, 1, 12.0, 1);
const wars = check_graha_yuddha(jd, 1); // Mode 1 = Lahiri

if (wars.length > 0) {
console.log("Planetary War Detected!");
wars.forEach((war) => {
console.log(
${war.planet1_name} vs ${war.planet2_name} (Diff: ${
war.longitude_diff.toFixed(
4,
)
}°),
);
console.log(Winner: Planet ID ${war.winner_id} (Brighter));
});
} else {
console.log("No planetary wars currently.");
}
`

$3

Calculate the current ruling planetary periods.

`typescript
import { calculate_vimshottari } from "./lib/panchangam.js";

// Birth details
const birth_moon_long = 45.5; // Example longitude
const birth_time_ms = new Date("1990-01-01").getTime();
const current_time_ms = Date.now();

const dasha = calculate_vimshottari(
birth_moon_long,
birth_time_ms,
current_time_ms,
);

console.log(Current Mahadasha: ${dasha.mahadasha});
console.log(Current Antardasha: ${dasha.antardasha});
console.log(Current Pratyantardasha: ${dasha.pratyantardasha});
console.log(
Ends: ${new Date(dasha.pratyantardasha_end_date).toLocaleDateString()},
);
`

$3

Calculate Ascendant and House Cusps for various systems (Placidus, Whole Sign,
etc.).

`typescript
import { calculate_houses, Location } from "./lib/panchangam.js";

const jd = swe_julday(2024, 1, 1, 12.0, 1);
const loc = new Location(28.6139, 77.2090, 0.0);

// 'P' = Placidus, 'W' = Whole Sign, 'E' = Equal
// Mode 1 = Lahiri Ayanamsha (Sidereal)
const houses = calculate_houses(jd, loc.latitude, loc.longitude, "P", 1);

console.log(Ascendant: ${houses.ascendant.toFixed(2)}°);
houses.cusps.forEach((cusp, i) => {
console.log(House ${i + 1}: ${cusp.toFixed(2)}°);
});
`

🛠️ Development

$3

- src/lib.rs: Wasm entry point.
- src/vedic/: Core algorithms (Tithi, Nakshatra, Dignity, Muhurat).
- src/astronomy/: Swiss Ephemeris wrappers and solvers.
- scripts/build_npm.ts: Build script.

$3

Run the verification suite:

`bash
deno test --allow-read --allow-env
``

License

MIT