This is a basic simulation of how a trigonometric graph (sin, cos, or tan) is created from a unit circle. Coded in Python 3.6 with the Pygame library. Use the big sin, cos, tan buttons to change the ...

Xingping Sun, Strictly Positive Definite Functions on the Unit Circle, Mathematics of Computation, Vol. 74, No. 250 (Apr., 2005), pp. 709-721 ...