Description : Implementation of Fast Fourier Transform over data imported from Excel using MATLAB.

FFT algo: You transform your data to s-domain by DFT and
Your time vector to a frequency vector by using sampling frequency.

X : time domain data Y = fft(X)

This Y vector consists of the average values of X (DFT).
Y is not equal to the values of X.

A short video explaining FFT --> click here