[Tutor] fyi - re: fft
jeffpeery at yahoo.com
Thu Aug 4 22:48:31 CEST 2005
hello, thought I'd post my progress with fiddling with the FFT.
I've been using fft by taking the real part with: myFFT = abs(FFT.fft())
the returned values are the fourier coefficients starting with a0
the old thing is that the output is symmetrical about N/2 where n>N/2 is the negative frequencies. also all outputs are multiplied by N, so to get anything meaningful (at least in my case) you must divide the output by N. so to get a0 you want myFFT/float(N).
I compared several inputs with the output and I also used the output to calculate the fourier series and it all looks like it should.
thanks for those that had input.
thats all I got.
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