See also:

• Science: Math: Numerical Analysis: Software: Fast Fourier Transforms  (7)

• CHIRP-Z transform for FFTs - Little known algorithm for calculating the FFT of a series of any length. Based upon Applied Statistics algorithms 117 and 83.
• Ernst Mayer - Fortran 90 codes for Fast Fourier Transforms and Discrete Weighted Transforms, for use in number theory research.
• Fast Fourier Transform code - By James Van Buskirk.
• FFTPK90 - Translation of fftpack and vfftpk to Fortran 95 by Simon Clarke.
• Jörgs Useful and Ugly FFT page - Code and links in Fortran and C for the Fast Fourier Transform.
• Pipelined phase-rotation FFT - By David O'Halloran. The Welchel phase-rotation FFT is a new form of the fast Fourier transform (FFT) that replaces data movement at runtime with equivalent multiplications by precomputed constants. The result is an FFT that is easy to pipeline.
• Romo's Free Software - OFFT, "Outrageously Fast Fortran Transpose", and BFFFT, "Blazingly Fast FFT, 2-Dimensional Vectorized Fast Fourier Transform" written in Fortran 90.
• A Short Demonstration Version of the FFT - Source code of a subroutine to transform (forward or inverse) a one-dimensional complex array in place.