In Parashara, a planet's sign and house are the primary tools. A planet in Libra (sign) in the 7th house (domain) is read as oriented toward relationships. The exact degree (7°15' vs 7°45') matters only for strength (combustion, aspect orbs).
In Nadi, every degree within a sign is a distinct zone, carrying its own signification. The Aries sign (0-30°) might be divided as: 0-5° = self, 5-10° = wealth, 10-15° = siblings, 15-20° = spouse/desires, 20-25° = children, 25-30° = enemies/health. A planet at 2° Aries speaks to the self; a planet at 18° Aries speaks to spouse.
This is different from Jaimini's nakshatra-based approach (nakshatras are star groups, unequal in size). It is also different from KP's sub-lord method (which divides nakshatras into 9 unequal parts). Nadi divides signs into 6 or 9 equal degree zones, depending on the text, and each zone has preset meanings.
Application: If Sun is at 7°15' Virgo, the Nadi reader looks up "Sun in 5-10° Virgo" and reads that section's interpretation (which might say "Wealth through intellectual work, peak at age 35"). The interpretation is preset in the nadi text; it is not derived from the chart's overall structure.
Strength of the method: Simplicity, specificity, and psychological richness. The interpretations in nadi texts are often poetic and detailed, resonating with clients.
Weakness: Lack of logical derivation. Why is Sun at 7° Virgo associated with "wealth through intellect, peak at 35"? The nadi text does not explain; it is presented as revealed knowledge. This makes the system hard to debug or improve.
The engine reads planetary degrees and maps them to nadi zones. You will examine your natal planets' degrees and see what the nadi system predicts for them, then cross-check against your actual life events.