walsh_transform, a Fortran90 code which implements versions of the Walsh and Haar transforms.
The programs, as printed in the reference, had a few typographical errors. Several programs, in particular FHT and FRT, could not be made to perform as described in the text, and hence have been omitted.
The information on this web page is distributed under the MIT license.
walsh_transform is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.
fftpack5, a Fortran90 code which implements the Fast Fourier Transform by Paul Swarztrauber and Dick Valent;
haar_transform, a Fortran90 code which computes the Haar transform of data.
sftpack, a Fortran90 code which implements the "slow" Fourier transform, intended as a teaching tool and comparison with the fast Fourier transform.
sine_transform, a Fortran90 code which demonstrates some simple properties of the discrete sine transform.
wavelet, a Fortran90 code which does some simple wavelet calculations;