fft_openmp, a C code which demonstrates the computation of a Fast Fourier Transform (FFT) in parallel, using OpenMP.
On an Apple PowerPC G5 with two processors, the following results were observed:
| Threads | N | Time | MegaFLOPS |
|---|---|---|---|
| 1 | 33,554,432 | 32.65 | 128.4 |
| 2 | 33,554,432 | 19.87 | 211.0 |
| 4 | 33,554,432 | 19.80 | 211.7 |
In the BASH shell, the program could be run with 2 threads using the commands:
export OMP_NUM_THREADS=2
./fft_openmp
The information on this web page is distributed under the MIT license.
fft_openmp is available in a C version and a C++ version and a Fortran90 version.
dijkstra_openmp, a C code which uses OpenMP to parallelize a simple example of Dijkstra's minimum distance algorithm for graphs.
fft_serial, a C code which demonstrates the computation of a Fast Fourier Transform, and is intended as a starting point for implementing a parallel version using OpenMP.
fftpack4, a C code which implements the Fast Fourier Transform (FFT) by Paul Swarztrauber and Dick Valent, translated by Andrew Fernandes;
fftw_test, a C code which illustrates the use of the fftw() library for Fast Fourier Transforms, by Matteo Frigo and Steven Johnson.
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sftpack, a C code which implements the "slow" Fourier transform, intended as a teaching tool and comparison with the fast Fourier transform.
sgefa_openmp, a C code which solves a linear system by Gaussian elimination, using OpenMP.
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