Ganitha Nirnayam - A Sanskrit Astronomical & Astrological Treatise

Like Laplace's Celestial Mechanics, Ganitha Nirnayam or Mathematical Formulae is a treatise on Astro Maths to compute the longitudes of planets.

This book uses the Sidereal system.

The Western method is to find the True Anomaly of the planet and then add to it The Argument of Perihelion ( a mathematical quantity ) to arrive at a planet's longitude

Theta = v + w

The Indian method is Longitude Corrected Thrice. First the mean longitude of the planet is calculated and then three trignometric corrections are given to find the true longitude of the planet.

First the Mean longitude is reduced by a mathematical process called Manda Kriya. Mandochha refers to Aphelion. By Manda Kriya the mean longitude is reduced to Manda Sphuta, the longitude obtained after the first trignometric correction