FFTW3
Fast Fourier Transforms
C Calling Examples

This directory contains examples of the use of the FFTW3 library by a C calling program.

FFTW3 is a library of C routines which can compute the Fourier transform very efficiently.

FFTW3 can compute the discrete Fourier transform of:

• complex data;
• real data;
• even-symmetric real data (cosine transform);
• odd-symmetric real data (sine transform);

The length of the data is not required to be a power of 2. Any length of data can be processed.

The data is not restricted to 1 dimensional vectors. FFTW3 can handle data that is 2 or 3 dimensional. In fact, the program can handle data with any dimensionality.

At the SCS, FFTW3 is installed on kachina and chili.

Usage:

At the SCS, the C include file is in /usr/local/include. A sample copy is also available in this directory.

At link time, you must include the FFTW3 library. At the SCS, this library is in /usr/local/lib. An appropriate command might be

        gcc myprog.c -lfftw3
      

Related Data and Programs:

FFTW3 may be called from a FORTRAN77 program.

FFTPACK is a FORTRAN90 library of FFT routines.

FFTPACK5 is a FORTRAN90 library of FFT routines.

GROMACS, is a molecular dynamics package which uses the FFTW3 library.

GSL is the Gnu Scientific Library, which includes a number of FFT routines.

NMS is a FORTRAN90 library which includes a number of FFT routines.

Author:

Matteo Frigo and Steven Johnson

Reference:

1. William Briggs, Van Emden Henson,
   The DFT: An Owner's Manual for the Discrete Fourier Transform,
   SIAM, 1995,
   ISBN13: 978-0-898713-42-8,
   LC: QA403.5.B75.
2. Elbert Brigham,
   The Fast Fourier Transform and Its Applications,
   Prentice-Hall, 1988,
   ISBN: 0133075052,
   LC: QA403.B74.
3. http://www.fftw.org,
   the FFTW homepage.
4. Matteo Frigo and Steven Johnson,
   User Manual for FFTW,
   fftw3.pdf.

Source Code:

• fftw3.h, the FFTW3 include file.

Examples and Tests:

• fftw3_prb.c, a sample calling program.
• fftw3_prb.csh, commands to compile, link and run the sample calling program.
• fftw3_prb_output.txt, the output file.

You can go up one level to the C source codes.