PowerSpectrum: improve diagnostic value power spectrum api #695
+349
−132
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Why this PR?
PowerSpectrum
. The benefits of this may not be evident in this PR, but a followup one will have pathological spectra constructed directly rather than ifft'ing the spectrum only to immediately fft it again.Tradeoffs
Increased size
Keeping the high frequency spectrum around does come at a cost, namely the increased memory footprint. For a typical calibration (100 kHz sample rate) this is about 4 MB worth of data per axis for passive, 8 for active.
Downsampling and frequency exclusion ranges
There is one annoying issue with showing the frequency exclusion ranges. Exclusion ranges are applied prior to downsampling, which means that downsampling can subsequently pull a point outside the exclusion ranges into it. This is not really a bug, as this allows us to make cuts smaller than the blocking size, but it can look weird.