how can I recover original frequencies from a data table acquired from osciloscope?

Could someone help me with this issue?

Supose that I made a fake signal from:

t=0:1:1023;
w1=(t/1023)*720;
w2=(t/1023)*360;
w3=(t/1023)*180;
w4=(t/1023)*90;

v=1+10*cosd(w1)+4*cosd(w2)+2*cosd(w3);
i=2+10*cosd(w1)+4*cosd(w2)+2*cosd(w4);

How can I recover all original frequencies (720, 360, 180, 90) if I have only a data table generated by equations above ? (and I don't know the equations)

Thanks a lot for your time.

Answer 1

[Daniel kiracofe]

well, fft() function is a good start. I'm guessing if you are asking this, then you don't know much about fft() function. This little tutorial I wrote may help you: http://mechanicalvibrationc.domain.com/Making_matlab_s_fft_functio.html