What is FFTW?
FFTW is a C subroutine library for computing discrete Fourier Transforms (DFTs) in one or more dimensions, of arbitrary input size, and both real and complex data. It is parallelized for parallel computing platform of both SMP machines or distributed-memory cluster systems.
FFTW version supported in different HPC system is listed at Scientific Software and Programming Tools
|module load fftw/3.3.9