Bharatiya Jyotihshastra (History of Indian Astronomy), translated by R. V. Vaidya v2.c12.s5.61

v2.c12.s5.61

A mathematician named Cakradhara, son of Vāmana, compiled this work and it has a commentary written by the author himself. In addition to this, there is a commentary on the work by Rāma, son of Madhusūdana, a resident of Pārthapura. The author has not given his date, but as he has quoted in his commentary some lines from Bhāskarācārya's Siddhānta Śiromaṇi, and Rāma, the commentator, has mentioned Śaka 1547 as the date of his commentary, the work must have been written some time between Śaka 1100 and 1500. His words, "kṣitipālamaulivilasadratna grahajñyāgraṇī cakradharaḥ" meaning "Cakradhara, the leading astronomer, and who is a jewel in the crown of kings" shows that he had the patronage of some king. The work has four chapters containing 26 verses in all. Dinakara, son of Ananta belonging to śāṇḍilya gotra wrote a commentary on it with examples in the Śaka year 1767. Yantracintāmaṇi is a kind of quadrant instrument. The observations taken with this instrument give the longitudes of the Sun and the Moon, and also the longitudes and latitudes of five planets, the desired time, and the ascendant true for that momemt, and such other things. The planetary positions and the ascendant are sāyana.