Jyotihshastra: Astral and Mathematical Literature c4.s5.3

c4.s5.3

The Parahita system was first embodied in the Grahacāranibandhana²³⁶ of Haridatta. Traditionally the date of the inception of the system was 683; since Haridatta is already quoted as an authority of Govindasvāmin in his Prakaṭārthadīpikā, written in the first half of the ninth century, 683 is not an unreasonable date for Haridatta. The GCN versifies the mean daily motions of the planets according to the Āryapakṣa, the sines of their equations at intervals in the argument of 3;45° (he calls these tables vākyas), the śīghra anomalies necessary for first and last stations, and the mean longitudes of the planets on 20 March 355; all of the numbers are expressed by the kaṭapayādi system. In another work—probably the lost Mahāmārganibandhana—Haridatta gave bīja corrections to the mean yearly motions of the planets, to be applied to the years following 522.