Bhaskara-I

Bhāskara I was a 7th-century Indian mathematician and astronomer who was the first to write numbers in the Hindu–Arabic decimal system with a circle for the zero, and who gave a unique and remarkable rational approximation of the sine function in his commentary on Aryabhata's work. This commentary, Āryabhaṭīyabhāṣya, written in 629, is among the oldest known prose works in Sanskrit on mathematics and astronomy to be completely extant today. He also wrote two astronomical works in the line of Aryabhata's school: the Mahābhāskarīya and the Laghubhāskarīya.