[SciPy-dev] fftw2 and fftw3  Matt Fishburn fishburn at MIT.EDU
Thu Dec 15 13:41:36 CST 2005  Arnd Baecker wrote: > Hi, > now
also the results for the fftw2 vs. fftw3 comparison on the >
Itanium 2 are there. > There is the same problem as on the other
machines, for example:  I coded the original FFTW3 patches, but
these were my first patches to  OSS and I still don't completely
understand scipy's build  process/tradeoff philosophy.  If no
one else wants to take a look at the  FFTW stuff I guess you're
stuck with me. :)  >> I am at complete loss of what is going on
as I don't understand >> fftpack at all. >> Could an fft expert
have a look or give some guidance on >> how to explore this
further?  In a nutshell, this is what I think is going on: FFTW
plans out the  transform before execution, pushing off as much
of the execution as  possible into the planning state.  FFTW3
plans have static memory  locations for plans, whereas FFTW2
plans do not.  This allows FFTW2  plans to be much more flexible
than FFTW3 plan