I would like to suggest an addition of the fast hadamard transform to the
following package:
org.apache.commons.math.transform
The class would be called:
FastHadamardTransformer
*1. A concise description of the new feature/enhancement.*
The new feature will implement the fast hadamard transform.
*2. References to definitions and algorithms.*
Definition of the hadamard transform:
http://en.wikipedia.org/wiki/Hadamard_transform#Definition
Unfortunately, Mathworld does not provide a very detailed definition.
http://mathworld.wolfram.com/HadamardTransform.html
An elegant algorithm for the fast hadamard transform can be found here:
http://www.archive.chipcenter.com/dsp/DSP000517F1.html
*3. Some indication of why the addition/enhancement is practically useful.*
The hadamard transform has applications in signal processing and data
compression.
