A program that compares the first second and fourth order approximations of the first derivative against the analytical or exact derivative

Objective: https://drive.google.com/open?id=1XkRFR0VCg4OcZN7M_g1c6aT1P5AZKEua I\'ve attached the main program file, along with the file for first order approximation, second order approximation and third order approximation.