Re: Can you trim a FFT?

From: "Steven G. Johnson" <stevenj@xxxxxxxxxxxx>
Date: Mon, 19 May 2008 21:32:55 -0700 (PDT)

On May 19, 6:52 am, shoo <JGBurg...@xxxxxxxxx> wrote:

I would [naively] like to know if there is a method of applying the
fft with the intention of only requiring a predetermind range of
frequency. hense no waste in the fft.

In principle, yes. What you are looking for is called a "pruned FFT"
and Google will turn up some useful references. In practice, the
savings (which are only in the log as Tim pointed out) aren't really
worth it, in my experience, unless you want only a tiny fraction of
the FFT outputs.

Regards,
Steven G. Johnson
.

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