FFTW is a library for computing the discrete Fourier transform (DFT) in one or more dimensions, of arbitrary input size, and of both real and complex data.
module help fftw
The manual is on the web http://www.fftw.org/
CINECA consultants can be reached through the addr: superc@cineca.it
More versions are available for portability issues. For listing all available versions:
modmap -m fftw