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May 27, 2022 03:28PM
Hi, Philipp-

I admit I got a bit lost in the description about what the actual question was. Can you please rephrase it directly?

If you are wondering about a factor of 2 difference in a log-plot-based comparison, then I suspect one "power" method is actually calculating magnitude---that is, power is (magnitude)^2, and when you take the log of that, the 2 comes down on the lefthand side:
log(magnitude^2) = 2 log(magnitude).
You are migrating among many software, so it is good to make sure what is being calc'ed in each---first whether it is really power or magnitude (=amplitude), and second that log() is really the consistent base of logarithm you want.

--pt
Subject Author Posted

3dPeriodogram and 1dFFT - How exactly is the power computed? Attachments

Philipp May 27, 2022 10:36AM

Re: 3dPeriodogram and 1dFFT - How exactly is the power computed?

ptaylor May 27, 2022 03:28PM

Re: 3dPeriodogram and 1dFFT - How exactly is the power computed?

Philipp May 27, 2022 03:58PM

Re: 3dPeriodogram and 1dFFT - How exactly is the power computed?

ptaylor May 27, 2022 08:52PM

Re: 3dPeriodogram and 1dFFT - How exactly is the power computed?

Philipp May 28, 2022 03:36AM

Re: 3dPeriodogram and 1dFFT - How exactly is the power computed?

ptaylor May 28, 2022 07:11AM

Re: 3dPeriodogram and 1dFFT - How exactly is the power computed? Attachments

Philipp May 28, 2022 11:03AM

Re: 3dPeriodogram and 1dFFT - How exactly is the power computed?

ptaylor May 31, 2022 05:41PM

Re: 3dPeriodogram and 1dFFT - How exactly is the power computed?

Philipp June 01, 2022 12:24AM



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