MATLAB has a built in function that will help interpolate between data points using a variety of methods (interp1). This is often used to create a finer resolution for a given set. Modify the interpolation program (interp_prog.m) to use the built-in function (interp1) to apply a "cubic" interpolation to the following set of data: x= -3:1:3 y(x) = [-1, -1, -1, 0, 1, 1 1] For a resolution of 0.2, rather than 1. Plot the original data as points and the cubic fit as a dashed line.