const float xy0 = 5.65685;
const float xy1 = 11.3137;
const float xy2 = 16.9705;
const float xy3 = 22.6274;
const float xy4 = 28.2842;
const float xy5 = 33.9411;
const float xy6 = 39.5979;
const float xy7 = 45.2548;
const float xy8 = 50.9116;
const float xy9 = 56.5685;
Why not use arrays?