tir, 21 09 2010 kl. 10:31 +0200, skrev JuanPi: > Hi everybody, > > According to FFTW > http://www.fftw.org/faq/section3.html#whyscaled > > the fft is not normalized...hence ifft(fft(y)) = length(y)*y To clear things up:
The fft is not normalized, but the ifft is normalized in such a way that ifft(fft(y)) == y In FFTW, ifft is not normalized this way, so ifft in FFTW and Octave/Matlab differs, but the fft's are the same. Normally, if one talks about a normalized fft, the normalization is fft(y)/sqrt(length(y)). This gives fft and ifft the same normalization /Peter ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ Octave-dev mailing list Octave-dev@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/octave-dev
