In the early stages of my program development, I came across an unknown term Sparsa Jyakkal in Ganita NIrnayam. A 12 page table giving math values for every 5 degrees. I thought I had to create a data file for the 12 page data . It will be a killer in terms of time and it will take me one weeks work. So I wanted to crack the code of the table,. I put sine and i didnt get true values. I put cos and again the same result. So I i put tan and it clicked ! Those were The Tan tables of Brahmagupta , and he had given tan values for every 5 degrees,. Spars jya = tan x and Sparsa chapa = a tanx