940?-1000?

Persian mathematician and astronomer who was a leader in the application of Greek geometric methodology among Muslim scholars. Al-Quhi (sometimes spelled al-Kuhi), served the Buyid dynasty, whose caliphs ordered him to make a number of astronomical observations. For this purpose, he directed the building of an observatory in Baghdad, at which he served as director following its opening in 988. He discussed geometric problems involving quadratic or cubic equations, and described a conic compass, or one with a leg of variable length, for drawing conic sections.