DashaFlow

A Vedic astrology calculation engine for Python, built on the Swiss Ephemeris with Sidereal Lahiri ayanamsha. Rooted in Brihat Parashara Hora Shastra (BPHS) and B.V. Raman's Hindu Predictive Astrology.

pip install dashaflow

Quick Start

import dashaflow

# Cast a natal chart
chart = dashaflow.cast_chart("1990-04-15", "14:30", 28.6139, 77.2090, "Asia/Kolkata")

print(chart["lagna"]["sign"])              # "Leo"
print(chart["planets"]["Moon"]["nakshatra"])  # "Jyeshtha" (for this birth data)
print(chart["planets"]["Moon"]["dignity"])    # "debilitated"
maha = chart["dashas"]["maha"]
print(maha["planet"] if maha else None)       # Current Mahadasha lord (None outside the 120-year span)
print(chart["yogas"])                         # Detected yogas

# Transits
transit = dashaflow.cast_transit(
    "2026-03-29", "1990-04-15", "14:30", 28.6139, 77.2090, "Asia/Kolkata"
)
print(transit["sade_sati"])

# Compatibility (Person 1 = Male, Person 2 = Female)
compat = dashaflow.calculate_compatibility(
    "1990-04-15", "14:30", 28.61, 77.21, "Asia/Kolkata",
    "1992-08-20", "09:15", 19.07, 72.87, "Asia/Kolkata",
)
print(f"Score: {compat['total_score']}/36")

# Muhurtha (electional astrology)
muhurtha = dashaflow.check_muhurtha("marriage", "2026-11-15", "10:30", 28.61, 77.21, "Asia/Kolkata")
print(muhurtha["verdict"])  # "auspicious" / "mixed_favorable" / "mixed" / "inauspicious"

# Career analysis
career = dashaflow.analyze_career("1990-04-15", "14:30", 28.61, 77.21, "Asia/Kolkata")
print(career["career_themes"])

API

Top-Level Functions

Sub-Module Access

from dashaflow.dasha import calculate_dashas
from dashaflow.matchmaking import calculate_ashtakoot
from dashaflow.shadbala import calculate_shadbala
from dashaflow.jaimini import calculate_jaimini_karakas, calculate_arudha_padas
from dashaflow.yoga import detect_yogas, detect_kaal_sarpa
from dashaflow.ashtakavarga import calculate_ashtakavarga, calculate_sodhita_ashtakavarga
from dashaflow.vimshopaka import calculate_vimshopaka
from dashaflow.yogini import calculate_yogini_dasha
from dashaflow.chara import calculate_chara_dasha
from dashaflow.errors import DashaFlowError, InvalidInputError, EphemerisError, CalculationError
from dashaflow import schemas  # published JSON Schemas + validate()
from dashaflow.muhurtha import ACTIVITY_RULES  # the 6 supported activity keys

cast_chart() Returns

Features

• Natal Chart — Lagna, 9 grahas, whole-sign houses, nakshatras with padas, dignities
• 14 Divisional Charts — D2, D3, D4, D7, D9, D10, D12, D16, D20, D24, D27, D30, D40, D60
• Planetary Strength — Dignity (B.V. Raman), combustion (BPHS orbs), Digbala, Shadbala (6-fold), Vimshopaka (20-pt), Ishta/Kashta Phala
• BPHS Aspects — 7th for all, special aspects for Mars (4th/8th), Jupiter (5th/9th), Saturn (3rd/10th)
• Vimshottari Dasha — 5 levels (Maha → Antar → Pratyantar → Sukshma → Prana), 120-year timeline
• Yogini Dasha — 36-year Tantric cycle (Maha, Antar, Pratyantar)
• Chara Dasha — Jaimini sign periods via sign-to-lord counts (K.N. Rao method)
• 24 Yoga Detections — Pancha Mahapurusha, Gajakesari, Budhaditya, Raj Yoga, Neecha Bhanga, Parivartana, Dhana, and more
• Ashtakavarga — SAV, BAV, Prashtara (source-level bindu contributions), Sodhita reductions + Sodhya Pinda
• Jaimini — 7 Karakas, Arudha Padas (A1–A12), Upapada Lagna, Karakamsha
• Compatibility — 8 Ashtakoot kutas (36 pts) + Mahendra, Stree Deergha, Vedha, Rajju, Kuja Dosha
• Muhurtha — 6 activity types with Panchang Suddhi and marriage doshas
• Career — D10 analysis with planet-career significations and domain recommendations
• Bhava Chalit — Equal-house chart from Lagna midpoint
• Avasthas — 5 planetary age-states per BPHS
• Kaal Sarpa, Graha Yuddha, Gandanta — Dosha and junction detection

Architecture

dashaflow/
├── __init__.py         Public API (5 functions + error taxonomy)
├── _validation.py      Input validation (dates, coordinates, timezones, paths)
├── errors.py           DashaFlowError, InvalidInputError, EphemerisError, CalculationError
├── _version.py         Single-sourced package version
├── vedic_calculator.py Core engine — Swiss Ephemeris computations
├── constants.py        Zodiac, nakshatras, dignity tables, house sets
├── nakshatra.py        Nakshatra lookup from longitude
├── panchang.py         Tithi, Vara, Yoga, Karana
├── yoga.py             Yoga detections + Kaal Sarpa, Graha Yuddha, Gandanta
├── dasha.py            Vimshottari Dasha (5 levels)
├── yogini.py           Yogini Dasha (36-year cycle)
├── chara.py            Chara Dasha (Jaimini signs)
├── vimshopaka.py       Shad-Varga 20-point strength
├── dignity.py          Dignity, combustion, digbala
├── ashtakavarga.py     SAV, BAV, Prashtara, Shodhana, Sodhya Pinda
├── jaimini.py          Karakas, Arudha Padas, Upapada, Karakamsha
├── shadbala.py         Six-fold strength + Ishta/Kashta Phala
├── matchmaking.py      16-factor compatibility + Kuja Dosha
├── muhurtha.py         Electional astrology
└── career.py           D10 career analysis

Ayanamsha

All calculations use Lahiri (Chitrapaksha) — the official standard of the Indian government and the most widely used system in Vedic astrology.

Extended Ephemeris

No .se1 data files ship with the package — positions come from the analytic Moshier fallback built into pyswisseph unless you supply data files. Inside ~1800–2400 AD this is high accuracy for chart purposes and reported as metadata["ephemeris_accuracy"] == "full". Births outside that range still compute, but the chart honestly flags reduced (Moshier fallback…) (plus a log warning). For maximum historical/far-future accuracy, download .se1 files from astro.com and pass the path:

chart = dashaflow.cast_chart("1200-03-10", "12:00", 28.61, 77.21, "Asia/Kolkata",
                              ephe_path="/path/to/extended/ephemeris")

Production Use

• Thread-safety: chart and transit calculations hold a process-wide lock around all Swiss Ephemeris calls — safe to call from threaded web servers (verified by an 8-way concurrency test). The locked section is ~10 ephemeris calls (milliseconds).
• Errors: dashaflow.errors defines DashaFlowError, InvalidInputError (a ValueError, so existing handlers keep working), EphemerisError, and CalculationError. Every chart passes an output-contract gate (required keys, planet fields, SAV=337 invariant) before it is returned.
• Observability: standard logging loggers (dashaflow.vedic_calculator, …) emit debug timings; each chart's metadata carries dashaflow_version, swe_version, ephemeris, ephemeris_accuracy, and computed_at_utc.
• Determinism: pass explicit query_date / transit_date for reproducible outputs (omitted dates default to today and are debug-logged).

References

• Brihat Parashara Hora Shastra — foundational text for Vedic astrology
• Hindu Predictive Astrology — B.V. Raman
• Swiss Ephemeris — high-precision astronomical computation

Limitations & Simplifications

This engine favors a lightweight, dependency-free design over exhaustive classical detail:

• Vimshottari Dasha uses the sidereal year (365.2563 days); sub-period boundaries keep full datetime precision internally but start/end strings remain date-only.
• Kemadruma Yoga applies classical Bhanga (cancellation by kendra planet from Moon, conjunction with Moon, or Moon in kendra from Lagna) — cancelled cases are not listed.
• Raj Yoga covers conjunction + dual lordship + aspect-sambandha; exchange-based (Parivartana) Raja effects are reported separately as Parivartana Yoga.
• Neecha Bhanga covers dispositor/exaltation-lord kendra placement plus aspect-sambandha; further classical variants (e.g. vargottama, mutual debilitation aspect) are not modeled.
• Graha Yuddha winner = higher ecliptic latitude, falling back to brightness precedence (Venus > Jupiter > Mercury > Saturn > Mars) when latitudes tie or are unavailable.
• Kaal Sarpa uses absolute longitudes (not sign-only); near-misses with one planet outside are reported as Partial.
• Shadbala implements Uchcha/Saptavargaja/Ojayugma/Kendra/Drekkana + linear Dig Bala + Natonnata/Paksha/Ayana Kala Bala + speed-based Chesta Bala + fixed Naisargika Bala + midpoint-normalized Drik Bala. Hora/Masa/Varsha Bala and Shodhana reductions are omitted.
• Bhava Chalit is the equal-house system from the Lagna midpoint (not Sripati/Bhava-Sandhi).
• Vimshopaka uses the Shad-Varga scheme with Panchadha-Maitri grades; exalted/mooltrikona/own score full 20, debilitated floors at 5.
• Sodhita Ashtakavarga follows Trikona + Ekadhipatya rules with 7-planet occupancy; Sodhya Pinda = Σ reduced bindus × Rashi Gunakar.
• Chara Dasha uses sign-to-lord exclusive counts (Savya forward / Apasavya backward, own-sign lord = 12y) with dual-lord strength resolution; cycle direction from the 9th-from-Lagna rule.

License

MIT