Talk:FFTW

message: I would like this page to mention which algorithm is used by FFTW. This could include a link to
"Category:FFT_algorithms" (I don't know how to make this link properly)
:This isn't an FFT algorithm, per se, it's an implementation of many FFT algorithms.  Also, according to the FFTW Documentation, FFTW uses a variety of algorithms depending on the length and type of input. Charles Simpson 15:33, 1 December 2006 (UTC)
replies: text: I've clarified the description of the algorithms used in FFTW in the article. (I normally don't edit this article, but since this was a simple question of fact that is well supported by published references, it seemed like WP:COI did not apply.) — Steven G. Johnson (talk) 05:27, 29 December 2009 (UTC)
thread_title: Link to Category:FFT_algorithms

message: I'd never heard of Dan Bernstein until I looked at this page. It seems to me that the mention of his "controversy" is redundant on this page. The link is to a web page of Bernstein's (i.e. not an article in a journal, or an independent web page) and having studied his library (and being well aware of FFTW), I am inclined to delete all mention of Bernstein and his library. Here are my reasons: unless someone can link in some third party sources on the controversy (i.e. not Bernstein's own material) I think the inclusion of the controversy violates NPOV. The Bernstein library hasn't been updated since 1999 and it is limited to powers of 2 lengths. Also, from reading its code, it seems to depend on providing a different function for each size of array. Great to use if your data array is a fixed size (and a power of 2) but no good if you sometimes want to pass a 256 element array and sometimes a 512 element array. FFTW in contrast, handles arbitrary sizes with a single call. Anyone else have a view? Sangwine 22:01, 12 December 2006 (UTC)
replies: text: Do not delete this valuable historical information.  The Bernstein-FFTW "controversy" was more of a cowboy feud and many records documenting it still exist on the Internet, search for them.  The facts of the feud were that Berstein's FFT code, even when you account for the out-of-order output, was faster at the time (1999) and that the FFTW guys refused to acknowledge this. Was it just academic disrespect or was it a coverup or was it just a bit too much cowboy mentality? It was probably a bit of all three.  In any case, it is important FFTW folklore.  Your comments about Bernstein's code being limited to powers of 2, while true, is completely irrelevant to this discussion.  (Requestion 16:47, 20 December 2006 (UTC)
replies: text:  The fact that djbfft only handles a few special cases is very relevant to this discussion. IMHO, some usenets posts by a disgruntled competitor don't deserve citation from the main FFTW page. Jon Harrop 11:05, 8 April 2007 (UTC)

text: I don't see what needs to be resolved.  We have Bernstein's opinion and we have Johnson's opinion. Surprisingly both opinions are more similar than they are different.  It isn't important who is right or wrong in this feud and it really isn't Wikipedia's place to decide either.  What is important is that this controversy was real and not some made up fiction.  We have two great sources of information straight from both of the horses mouths and I think this is about as resolved as it possibly can get.  We need to remember that the purpose of Wikipedia is to store a truthful record of history and sometimes parts of that history will be unflattering.  What I worry about is what happens when history is deleted?  Some of the mailing lists on the Internet that documented this event have been purged.  What happens when they are all purged and Bernsteins pages are deleted? My hope is that Wikipedia retains an accurate record. (Requestion 17:46, 22 December 2006 (UTC)
replies: text: How does the article include my opinion?  (Remember also that Wikipedia is not intended as a source of material not available elsewhere, and in fact this would be against policy.) —Steven G. Johnson 17:48, 24 December 2006 (UTC)

text: Given that (a) there are no articles for individual FFTW versions, and (b) these data applied to a long-deprecated version of FFTW (and of another library that is no longer updated), would it be prudent to shuffle these away somewhere under ==Previous versions== or ==History== or some such? → ɛɹin ♃ 15:03, 17 July 2008 (UTC)
thread_title: Bernstein "controversy"

message: It doesn't seem appropriate for the article to link to my userpage; doesn't that violate Wikipedia:Self-references to avoid? —Steven G. Johnson (talk) 00:12, 6 November 2008 (UTC)
thread_title:  link to User:Stevenj not appropriate? 

message: :FFTW ... is a software library for computing discrete Fourier transforms (DFTs), developed by Matteo Frigo and Steven G. Johnson at the MIT Laboratory for Computer Science.
Matteo Frigo was at the MIT Laboratory for Computer Science (LCS) when FFTW was first developed, but I was in the MIT Physics Department.  (I'm currently in MIT's Department of Mathematics, and Matteo has had several different positions, so there is not presently any direct association between FFTW and LCS/CSAIL.)
—Steven G. Johnson (talk) 05:28, 5 December 2008 (UTC)
thread_title:  correction 

message: I'm not sure if Wikipedia is the place for this, but I wanted to know if it would be appropriate to also add an external link showing the basic C implementation of the FFTW libraries. I have been using my implementation of FFTW for a while now at Griffith University, Australia for Signal processing and I constantly have students asking me how to implement the most basic FFT and IFFT in C. And I thought since Wikipedia is usually their first point of call when researching, could it also point them in the right direction for implementation. Something like: C Programming: The reconstruction of the Fast Fourier transform of a real signal using FFTW libraries for the most basic implementation, or something similar.
—Roger Chappel (talk) 19:48, 17 June 2011 (UTC)
thread_title:  External Links