HARMFIT: Sinusoidal harmonic curve fitting

Computes harmonics of a phase signal

This is the core formula of discrete Fourier transform: it simply computes the amplitude and phase shift of fundamental or harmonics of a phase signal.

Example:

t = linspace(0,2*pi);

x = 2*cos(t + pi/2) - cos(3*t) + rand(size(t));

harmfit(t,x,1:4)

returns estimations of amplitudes/phases for the first four harmonics.