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FFTW is a C subroutine library for computing the discrete Fourier transform in one or more dimensions of arbitrary input size, and of both real and complex data. FFTW v2.1.5 and FFTW v3.3 are available for the Cray XE6 system and distributed with the Cray Programming Environment.

How to use FFTW

% module load fftw

To see which versions of FFTW are available. Use

%module avail fftw

To compile and link a sequential 1D code :

% ftn test1D.f $FFTW_POST_LINK_OPTS -lfftw

To compile and link MPI 3D code :

% ftn test3D.f $FFTW_POST_LINK_OPTS -ldfftw_mpi -ldfftw

The order in which libraries are given is important.

Examples (coming soon)