Romberg Integration

A numerical integration that changes the base points of the trapezoid in evaluating the integral, thus giving better estimates

It is an iterative approach of numerical integration for functions, adapted from the classical Trapezoidal rule. It asks the user what termination criterion to employ, either a %relative error or number of iterations. A 1st iteration has a local truncation error of O(h^4); 2nd iteration an error of O(h^6); 3rd iteration an error of O(h^8), and so on.