ZERNFUN.m and ZERNFUN2.m compute the Zernike functions Znm(r,theta). These functions, which form an orthogonal basis on the unit circle, are used in disciplines such as astronomy, optics, optometry, and ophthalmology to characterize functions and data on a circular domain. ZERNPOL.m computes the Zernike polynomials Znm(r), which are the radial portion of the Zernike functions.
A MATLAB Digest article describing the use of the Zernike functions for analyzing optics data (using a LASIK surgery data as an example) also is available, on the File Exchange as a PDF,

and in HTML at:

https://www.mathworks.com/company/newsletters/articles/analyzing-lasik-optical-data-using-zernike-functions.html