Planetary Strengths¶

The strengths module implements four classical Jyotish strength systems. Each quantifies a planet's power from a different angle.

1. Shadbala (Six-Fold Strength)¶

Shadbala measures six independent sources of planetary power, each contributing up to 30 points. Combined, they give a total score (Rupa/Virupas) and a percentage.

`calculate_shadbala`¶

calculate_shadbala(context: ShadbalaPlanetContext) -> dict

Computes all six Balas and returns their scores.

Return keys:

Key	Description	Range
`sthana_bala`	Positional strength	0–30
`dig_bala`	Directional strength	0–30
`kala_bala`	Temporal strength	0–30
`paksha_bala`	Lunar phase strength	0–30
`chesta_bala`	Motional strength	0–30
`drishti_bala`	Aspectual strength	0–30
`total_shadbala`	Sum of all six	0–180
`shadbala_percentage`	As percentage of maximum	0–100

Individual Bala Functions¶

`calculate_sthana_bala`¶

calculate_sthana_bala(
    planet_code: str,
    rasi_number: int,
    *,
    retrograde: bool
) -> float

Positional strength based on sign placement (exaltation, own sign, moolatrikona, friend, enemy, debilitation) and retrograde status.

`calculate_dig_bala`¶

calculate_dig_bala(planet_code: str, house_number: int) -> float

Directional strength — each planet is strongest in a specific kendra house:

Planet	Strongest House
Sun, Mars	10th (south)
Moon, Venus	4th (north)
Saturn	7th (west)
Jupiter, Mercury	1st (east)

`calculate_kala_bala`¶

calculate_kala_bala(planet_code: str, *, night: bool) -> float

Temporal strength — some planets are stronger by day (night=False), others by night.

Stronger by Day	Stronger by Night
Sun, Jupiter, Venus	Moon, Mars, Saturn
Mercury (neutral)	—

`calculate_paksha_bala`¶

calculate_paksha_bala(planet_code: str, moon_phase: float) -> float

Lunar phase strength (Sukla/Krishna Paksha). The Moon and Jupiter are stronger in the bright half; Mars and Saturn in the dark half.

`calculate_chesta_bala`¶

calculate_chesta_bala(
    planet_code: str,
    *,
    retrograde: bool,
    avg_speed: float
) -> float

Motional strength — retrograde planets and planets moving faster than average receive higher scores.

`calculate_drishti_bala`¶

calculate_drishti_bala(
    other_planets: list[tuple[str, bool]]
) -> float

Aspectual strength from planets aspecting this planet. Each tuple is (planet_code, is_benefic).

2. Vimshopaka Bala (20-Point Strength)¶

Measures dignity across multiple divisional charts (vargas). The maximum score is 20 points.

`compute_vimshopaka_bala`¶

compute_vimshopaka_bala(
    planet_longitudes: dict[str, float],
    *,
    scheme: str = "shodasavarga"
) -> VimshopakaBalaReport

Schemes¶

Scheme	Vargas Used	Notes
`shadvarga`	D1, D2, D3, D9, D12, D30	6 charts
`saptavarga`	D1–D9 + D12, D30	7 charts
`dasavarga`	10 charts	Classical set
`shodasavarga`	All 16 vargas D1–D60	Most comprehensive (default)

Dignity Scores¶

Dignity	Score
`EXALTATION`	20
`MOOLATRIKONA`	18
`OWN_SIGN`	15
`GREAT_FRIEND`	12
`FRIEND`	10
`NEUTRAL`	7.5
`ENEMY`	5
`GREAT_ENEMY`	2.5
`DEBILITATION`	2

Strength Labels¶

Score Range	Label
≥ 18	PARIJATA
≥ 16	UTTAMA
≥ 13	GOPURA
≥ 10	SIMHASANA
≥ 6	PARAVATA
≥ 4	DEVALOKA
≥ 2	BHOOLOKA
< 2	NARAKA

3. Bhava Strength (House Strength)¶

Scores each bhava (house) by combining occupant planets, lord dignity, aspects, and optionally Ashtakavarga points.

`calculate_bhava_strength`¶

calculate_bhava_strength(
    context: BhavaStrengthContext,
    weights: BhavaStrengthWeights = DEFAULT_WEIGHTS
) -> BhavaStrengthSummary

Default Weights¶

Factor	Default Weight
Benefic occupant	+2.0
Malefic occupant	−2.0
Lord exalted	+3.0
Lord debilitated	−3.0
Benefic aspect	+1.0
Malefic aspect	−1.0
Ashtakavarga multiplier	0.5

4. Aspect Strength¶

Calculates the strength of planetary aspects within the natal chart.

`calculate_aspects_with_strength`¶

calculate_aspects_with_strength(
    planet_longitudes: dict[str, float]
) -> AspectStrengthReport

Aspect Types¶

Type	Orb
`CONJUNCTION`	0°
`OPPOSITION`	180°
`TRINE`	120°
`SQUARE`	90°
`SEXTILE`	60°
`SEVENTH`	210°/150° — full-sign 7th house aspect

Special Aspects¶

Certain planets cast full aspects to non-standard houses (in addition to the 7th):

Planet	Special Houses Aspected
Mars	4th and 8th
Jupiter	5th and 9th
Saturn	3rd and 10th

`AspectStrengthReport`¶

Field	Type	Description
`aspects`	`list[Aspect]`	All detected aspects
`strongest_aspect`	`Aspect \| None`	Highest-strength aspect
`total_aspects`	`int`	Count of aspects found

Planetary Strengths¶

1. Shadbala (Six-Fold Strength)¶

calculate_shadbala¶

Individual Bala Functions¶

calculate_sthana_bala¶

calculate_dig_bala¶

calculate_kala_bala¶

calculate_paksha_bala¶

calculate_chesta_bala¶

calculate_drishti_bala¶