Now it's time for us to demonstrate how to add a new function. The function we are going to deal with is a modified version of the original `Levy` function and is the 13^{th} version known to exist. This function is a minimization function.

The function itself, which you can find in the visual workbench source code, looks like this:

public double LevyFunction13(double[] data){double x1 = data[0];double x2 = data[1];double term1 = Math.Pow(Math.Sin(3 * Math.PI* x1), 2);double term2 = Math.Pow((x1 - 1), 2) * (1 + (Math.Pow(Math.Sin(3 * Math.PI* x2),2)));double term3 = Math.Pow((x2 - 1), 2) * (1 + (Math.Pow(Math.Sin(2 * Math.PI* x2), 2)));return term1 + term2 + term3;}

Definitely a lot of math there, right? Many times, ...