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Power spectrum VI and number of samples

Please look at the Help in the part where it is explained about the number of samples. 

It is not clear to me what happens if the number of samples is not respecting what is said in the help. 

That is I cannot understand if the results from Power Spectrum VI are reliable or not when the number of samples is not factorable as the product of small prime numbers. 

Is it used zero padding or what? In the block diagram a library is called, so I cannot figure out what it is doing. 

Thanks

 

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You can always compute a Discrete Fourier Spectrum "by hand", one frequency at a time.  Do you understand spectral analysis, and the math behind it?  Do you understand the difference between an FFT (Fast Fourier Transform) and a DFT (Discrete Fourier Transform) (hint -- it boils down to the difference between n ln n and n^2).

 

You might also look at using windowing to transform your set of data points to a (larger) set whose size is a power of two, thereby gaining the efficiency of the FFT at a small cost of the Window filter.

 

Bob Schor

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