Abū al-Wafāʾ, Muḥammad ibn Muḥammad ibn Yaḥyā ibn Ismāʿīl ibn al-ʿAbbās al-Būzjānī (10 June 940 – 15 July 998) was a Persian mathematician and astronomer who worked in Baghdad. He made important innovations in spherical trigonometry, and his work on arithmetics for businessmen contains the first instance of using negative numbers in a medieval Islamic text. He is also credited with compiling the tables of sines and tangents at 15' intervals.
Thank you, Gerard of Cremona, 13Century for translating Arabic medical texts. Especially, works of Muslim Ibn Sina/Avicenna (FATHER OF MEDICINE are said to have been made by order of the emperor Frederick II .Wikipedia, the free encyclopedia