Converting an Isosurface to Nurbs

Hello everyody!

I'm using Matlab for my research and I have very complex mathematical surface formula that include sinus and cosine functions . I used isosurface command to figure the mathematical surface and now I have to convert the shape to NURBS. Is there any easy way to obtain NURBS using only mathematical formulas. What do you recommend to me to solve my problem?

Thanks for your interest...