Harmonics and their Magnitude values

[khanna]

Hello,
I am new to python, my problem is to find the harmonics values of the given signal after applying FFT(Fast fourier Transform) and their corresponding amplitude values.
I am able to find fundamental frequency and its magnitude value, but am not able to find next harmonics values and their magnitude values.
Let's Think F is the Fundamental Frequency , 2F, 3F, 4F are their harmonics values but am not getting logic behind to find their corresponding magnitude values in python and how to display harmonics values on the graph.


Thanks in advance.

[buran]

Hello and welcome to the forum.
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[khanna]

This is the code for FFT of a give signal x, the fundamental frequency is getting correct but am not able to find next harmonics values and their corresponding amplitude values.

nfft = len(x)
nfft2 = 2**nextpow2(nfft)
ff = fft(x, nfft2)
fff = (ff[: nfft2/2])
#xfft = np.ndarray Fs*[: (nfft2/2-1)/nfft2]
xf = np.linspace(0.0, 1.0/(2.0*T), nfft2/2)
plt.plot(xf, abs(fff))
plt.show()
idx = np.argmax(np.abs(fff))
print('Fundamental frequency :',  xf[idx])

[Larz60+]

Is this helpful? https://bl.ocks.org/fasiha/957035272009e...936a6af2eb

[khanna]

Thanks for the reply..
I want to find next 6 harmonics values and their corresponding magnitude values..
The link which was given , I referred previously but i didn't get..

Thanks in advance.