HI all, do yo know what algorithm does MATLAB's fft function based on? I read from MATLAB's help, it is something called FFTW. Is it a radix 2 or radix 4 or anything else? Thank you.
FFT in MATLAB, do they use radix 2 or radix 4 algorithm>
Started by ●May 11, 2007
Reply by ●May 11, 20072007-05-11
A.E lover wrote:> HI all, > > do yo know what algorithm does MATLAB's fft function based on? I read > from MATLAB's help, it is something called FFTW. Is it a radix 2 or > radix 4 or anything else? > > Thank you. >fftw is open-source, you should be able to find that info in a web search (or look at the code...) -- Tim Wescott Wescott Design Services http://www.wescottdesign.com Posting from Google? See http://cfaj.freeshell.org/google/ Do you need to implement control loops in software? "Applied Control Theory for Embedded Systems" gives you just what it says. See details at http://www.wescottdesign.com/actfes/actfes.html
Reply by ●May 11, 20072007-05-11
Aloha, A.E lover wrote:> do yo know what algorithm does MATLAB's fft function based on? I read > from MATLAB's help, it is something called FFTW. Is it a radix 2 or > radix 4 or anything else?Read the algorithm part of the documentation (doc fft). The fft decides heuristically which decomposition is used and can use radix 2+4, prime-factor algo. and split-radix algo. Wishing a happy day, LOBI
Reply by ●May 11, 20072007-05-11
A.E lover wrote:> HI all, > > do yo know what algorithm does MATLAB's fft function based on? I read > from MATLAB's help, it is something called FFTW. Is it a radix 2 or > radix 4 or anything else?Mixed radix (ie neither 2 nor 4). See http://www.fftw.org/ Erik -- ----------------------------------------------------------------- Erik de Castro Lopo ----------------------------------------------------------------- "Working with Perforce in my day job makes me really appreciate just how good GNU Arch is." -- Erik de Castro Lopo
Reply by ●May 11, 20072007-05-11
See my answer to the author's duplicate post (grrr) "FFT in Matlab" to comp.soft-sys.matlab: http://groups.google.com/group/comp.soft-sys.matlab/msg/b50dd37e0603d326 Regards, Steven G. Johnson (FFTW co-author)