Fast Walsh Transform
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A version of this applet using the native VM is available here.

Fast Walsh Transform Applet

This applet performs the Walsh transform on its inputs.

This transform is useful for computing the non-linearity of boolean functions with arbitrary numbers of inputs - an attribute of interest to designers of cyphers.

Type in the entries in the logic table of the boolean function on the left - e.g. 1 0 0 1 0 1 1 0. Put spaces, commas or carraige returns between the entries. Then hit the button to perform the transform.

The source code is available here:

The code was based on an algorithm described by Terry Ritter.

Links to Ritter's web pages

[Measuring Boolean Function Nonlinearity by Walsh Transform]
[Walsh-Hadamard Transforms - a literature survey]

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