This is FFTW, a collection of fast C routines to compute the Discrete Fourier Transform in one or more dimensions. `OFFICIAL' CODE: The doc/ directory contains the manual in texinfo, postscript, info, and HTML formats. Frequently asked questions and answers can be found in the FAQ/ directory in a variety of formats (including HTML). The fftw/ directory contains the source code for the complex transforms, and the rfftw/ directory contains the source code for the real transforms. Large portions of the source are automatically generated by a program in the gensrc/ directory (written in Objective Caml). You do not need this program to use FFTW, since FFTW comes with a default set of pregenerated codelets. You are, however, welcome to look at and play with the generator (see the FFTW manual for more information). The threads/ directory contains an parallel version of FFTW (for shared-memory machines) that uses threads. See the "Multi-threaded FFTW" section of the manual for more information. The mpi/ directory contains a parallel version of FFTW for transforms on machines with MPI. (This code, unlike our other two parallel transforms, supports distributed memory machines.) See the "MPI FFTW" section of the manual for more information. fortran/ contains some constant definitions for using FFTW from Fortran (see the FFTW manual), and also a small example program. Installation instructions are provided in the manual (don't worry, it is straightforward). `UNOFFICIAL' CODE (for you to play with): matlab/ contains code that allows you to call FFTW from MATLAB. The cilk/ directory contains an parallel version of FFTW written in Cilk. Cilk is a cool C-like language in which you can write spawn foo() : foo will be executed in parallel with the main thread and the cost of spawn is just a few cycles (compare this with all the mess you have to do to create a posix thread and pay 3000 cycles for it). More info on Cilk can be found at http://supertech.lcs.mit.edu/cilk/. CONTACTS -------- FFTW was written by Matteo Frigo and Steven G. Johnson. You can contact them at fftw@fftw.org. The latest version of FFTW, benchmarks, links, and other information can be found at the FFTW home page (http://www.fftw.org). You can also sign up to the fftw-announce mailing list to receive (infrequent) updates and information about new releases; to do so, go to: http://www.fftw.org/mailman/listinfo/fftw-announce