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We appreciate your patience as we improve our online experience.
04-24-2019 03:12 PM
Any idea how I can add a limit curve on an FFT plot? The limit I want to use is as follow:
The linear ramp is obviously the tricky part!
Ben64
04-24-2019 04:42 PM
04-25-2019 02:08 AM
04-25-2019 07:57 AM
@GerdW wrote:Well, in the end it should be just (rather) simple math involving some logarithmic functions… 😄
Not so simple, the math part might be easy but how to create the limit and integrate it with the limit testing vi is not trivial. You need to define the limit values for the frequencies f0 + n*df of the resulting FFT.
Ben64
04-25-2019 09:07 AM
Are you sure you aren't over-thinking this? Or maybe I'm under-comprehending...
Why can't limit testing be handled with a lookup table that interpolates between the small # of corner points? If needed, you can do log-weighted intepolation. Or you could go ahead and precompute the entire "curve" once you know what dF spacing is needed.
So what am I not following?
-Kevin P