11 Feb
2012
11 Feb
'12
7:46 a.m.
11.02.2012 11:52, Nicolas Rougier kirjoitti:
FFTW documentation (http://www.fftw.org/fftw2_doc/fftw_3.html) states that:
"FFTW is best at handling sizes of the form 2^a*3^b*5^c*7^d*11^e*13^f, where e+f is either 0 or 1."
But the code from fftconvolve is only using (internally) sizes that are power of two, is there a specific reason ?
The underlying library is not FFTW, so the FFTW documentation does not apply. However, IIRC, FFTPACK had factorizations for 2^a*3^b*5^c, so there might be room for similar improvement. However, one would need to check if there are some additional restrictions. -- Pauli Virtanen