About Ellipse. Diameter = Major axis; Radius=Semi Major Axis. Equations same. pi r**2 and 2 pi r. Important is Deergha vritta, as planets revolve in elliptical orbits. 360/72 = 5, one unit. Tan tables of Brahma Sphuta Siddhanta gives values correcly ( Sparsa Jyakkal ). Jya mithi became Geometry, Trignon is trikona and Trikonamithi became Trignometry. Western origin of Internet is accepted but Maths & Astronomy originated from Ind !