Harmonic distortion of a input signal

[Gregory Ewing]

killybeard91 at gmail.com wrote:
> One more question. Function np.argmax returns max of non-complex numbers ? 
> Because FFT array of my signal is complex.

You'll want the magnitudes of the complex numbers.
Actually the squares of the magnitudes (assuming the
data from the oscilloscope represents voltages),
because you're after a ratio of powers.

-- 
Greg