Power Spectra for Analytic and Numerical Data
Consider a function defined by , in which you can vary the parameters , , , and . This Demonstration calculates the power spectrum of based on the method described in . In addition, the power spectrum of raw data is obtained. Power spectra represent a generalization of Fourier analysis, applicable even when the Fourier transform is not well defined.
 K. J. Beers, Numerical Methods for Chemical Engineering, Cambridge: Cambridge University Press, 2007.