vedic_panchanga_dart 0.1.0

A Dart port of PyJHora for Vedic astrology panchanga calculations. Provides accurate calculations for Tithi, Nakshatra, Yoga, Karana, sunrise/sunset, and planetary positions.

vedic_panchanga_dart

A comprehensive Dart port of PyJHora for Vedic astrology panchanga calculations. Provides accurate calculations for traditional Hindu calendar elements and planetary positions using the Swiss Ephemeris.

Features

✨ Complete Panchanga Calculations

• 🌅 Sunrise, sunset, moonrise, moonset
• 🌙 Tithi (lunar day) - all 30 tithis
• ⭐ Nakshatra (lunar mansion) with pada - all 27 nakshatras
• 🔄 Yoga - all 27 yogas
• 📆 Karana - all 11 karanas
• ♈ Moon's Rasi (zodiac sign)

🔭 Astronomical Features

• Planetary positions (Sun, Moon, Mars, Mercury, Jupiter, Venus, Saturn, Rahu, Ketu)
• Sidereal longitude calculations
• Retrograde planet detection
• Multiple ayanamsa modes (LAHIRI, KP, RAMAN, TRUE_CITRA, etc.)

🎯 High Precision

• Based on Swiss Ephemeris for accurate planetary positions
• Supports all major ayanamsa systems
• Inverse Lagrange interpolation for precise event timings

Installation

Add this to your package's pubspec.yaml file:

dependencies:
  vedic_panchanga_dart: ^0.1.0

Then run:

dart pub get

Or for Flutter projects:

flutter pub get

Usage

Basic Example

import 'package:vedic_panchanga_dart/vedic_panchanga_dart.dart';

void main() {
  // Initialize the service with desired ayanamsa mode
  PanchangaService.initialize(ayanamsaMode: 'LAHIRI');

  // Create a place (name, latitude, longitude, timezone in hours)
  final chennai = Place('Chennai', 13.0827, 80.2707, 5.5);

  // Calculate panchanga for a specific date
  final date = DateTime(2024, 10, 28);
  final panchanga = PanchangaService.calculatePanchanga(date, chennai);

  // Print the complete panchanga
  print(panchanga);
}

Output Example

Panchanga for 2024-10-28 at Chennai
============================================
Weekday: Monday
Sunrise: 06:10:23 AM
Sunset: 05:52:14 PM
Day Length: 11.70 hours
Night Length: 12.30 hours

Tithi: Saptami (05:30 - 18:45)
Nakshatra: Rohini Pada 3 (04:20 - 19:30)
Yoga: Vyaghata (ends at 15:22)
Karana: Bava (ends at 18:45)
Rasi: Taurus (ends at 20:15)

Moonrise: 11:30:45 AM
Moonset: 10:45:22 PM
============================================

Calculate Individual Elements

import 'package:vedic_panchanga_dart/vedic_panchanga_dart.dart';

void main() {
  PanchangaService.initialize();
  
  final place = Place('Mumbai', 19.0760, 72.8777, 5.5);
  final jd = PanchangaUtils.gregorianToJd(2024, 10, 28);

  // Calculate sunrise/sunset
  final sunrise = PanchangaService.sunrise(jd, place);
  print('Sunrise: ${sunrise['timeString']}');

  // Calculate tithi
  final tithi = PanchangaService.tithi(jd, place);
  print('Tithi: ${tithi.name}');

  // Calculate nakshatra
  final nakshatra = PanchangaService.nakshatra(jd, place);
  print('Nakshatra: ${nakshatra.name} Pada ${nakshatra.pada}');

  // Get planet positions
  final planets = PanchangaService.planetPositions(jd, place);
  for (final planet in planets) {
    print(planet);
  }
}

Different Ayanamsa Modes

// Use Krishnamurti Paddhati (KP) system
PanchangaService.initialize(ayanamsaMode: 'KP');

// Use Raman ayanamsa
PanchangaService.initialize(ayanamsaMode: 'RAMAN');

// Use True Citra ayanamsa
PanchangaService.initialize(ayanamsaMode: 'TRUE_CITRA');

Available ayanamsa modes:

• LAHIRI (default) - Most commonly used in India
• KP - Krishnamurti Paddhati
• RAMAN - B.V. Raman's ayanamsa
• TRUE_CITRA - True Chitra Paksha ayanamsa
• TRUE_REVATI - True Revati ayanamsa
• ARYABHATA - Aryabhata's ayanamsa
• SURYASIDDHANTA - Surya Siddhanta ayanamsa
• And more...

JSON Export

final panchanga = PanchangaService.calculatePanchanga(date, place);
final json = panchanga.toJson();
print(json);

API Reference

PanchangaService

Main service class for all calculations.

Methods:

• initialize({String ayanamsaMode}) - Initialize with ayanamsa mode
• calculatePanchanga(DateTime date, Place place) - Get complete panchanga
• sunrise(double jd, Place place) - Calculate sunrise
• sunset(double jd, Place place) - Calculate sunset
• moonrise(double jd, Place place) - Calculate moonrise
• moonset(double jd, Place place) - Calculate moonset
• tithi(double jd, Place place) - Calculate tithi
• nakshatra(double jd, Place place) - Calculate nakshatra
• yoga(double jd, Place place) - Calculate yoga
• karana(double jd, Place place) - Calculate karana
• moonRasi(double jd, Place place) - Calculate moon's rasi
• planetPositions(double jd, Place place) - Get all planet positions
• siderealLongitude(double jdUtc, int planet) - Get planet's sidereal longitude

PanchangaUtils

Utility functions for conversions and calculations.

Methods:

• gregorianToJd(year, month, day, {hour, minute, second}) - Convert to Julian Day
• jdToGregorian(jd) - Convert from Julian Day
• norm360(degrees) - Normalize angle to 0-360
• toDms(decimalHours, {asString}) - Convert to hours:minutes:seconds
• inverseLagrange(x, y, yTarget) - Inverse Lagrange interpolation

Models

Place

• Represents geographical location with timezone

PanchangaData

• Complete panchanga information for a day

TithiInfo

• Tithi number, name, start/end times

NakshatraInfo

• Nakshatra number, name, pada, start/end times

YogaInfo

• Yoga number, name, end time

KaranaInfo

• Karana number, name, end time

RasiInfo

• Rasi number, name, end time

PlanetPosition

• Planet longitude, latitude, speed, retrograde status, rasi

Background

This package is a Dart port of the excellent PyJHora Python library by @naturalstupid. PyJHora itself is based on algorithms from PVR Narasimha Rao's JHora software, a widely respected tool in Vedic astrology.

Porting Notes

The port maintains the same calculation accuracy as PyJHora by using:

• Swiss Ephemeris (via the sweph package)
• Same interpolation algorithms
• Same ayanamsa modes and constants

Limitations

• Requires Swiss Ephemeris data files (handled automatically by the sweph package)
• Currently supports core panchanga features
• Advanced features (dashas, divisional charts, yogas) planned for future releases

Roadmap

• ❌ Vimsottari Dasha calculations
• ❌ Divisional charts (D-1 to D-144)
• ❌ Advanced yoga detection
• ❌ Ashtakavarga calculations
• ❌ Planetary aspects and relationships
• ❌ Support for other calendar systems

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the GNU Affero General Public License v3.0 (AGPL-3.0) - see the LICENSE file for details.

This license is chosen to match the original PyJHora license. The AGPL-3.0 ensures that:

• The source code must remain open
• Any modifications must also be open-sourced
• Network use counts as distribution (important for web applications)

Credits

• PyJHora by @naturalstupid - Original Python implementation
• PVR Narasimha Rao - JHora software and algorithms
• Swiss Ephemeris - Astronomical calculations
• sweph package - Dart bindings for Swiss Ephemeris

References

• PyJHora: https://github.com/naturalstupid/pyjhora
• Swiss Ephemeris: https://www.astro.com/swisseph/
• JHora: https://www.vedicastrologer.org/jh/
• Vedic Astrology: "Vedic Astrology - An Integrated Approach" by PVR Narasimha Rao

Support

If you find this package useful, please give it a ⭐ on GitHub and a 👍 on pub.dev!

For bugs and feature requests, please file an issue on GitHub.