[R] Error Correcting Codes, Simplex

[Thomas Lumley]

On Tue, 17 Oct 2006, Richard Graham wrote:

> On 10/16/06, Björn Egert <begert at ipb-halle.de> wrote:
>> On 10/8/06, Egert, Bjoern <begert at ipb-halle.de> wrote:
>>>> Hello,
>>>>
>>>>   Is there a way in R to construct an (error correcting) binary code
>>>>   e.g. for an source alphabet containing integers from 1 to say 255
>>>>   with the property that each pair of distinct codewords of length m
>>>>   is at Hamming distance exactly m/2 ?
>>>>
>>>>   I was suggested to use so called simplex codes, which should be
>>>>   fairly standard, but I haven't found a direct way via R packages
>>>>   to do so, that's why I ask whether there might be in indirect way
>>>>   to solve this problem.


The "survey" package has a function hadamard() to construct Hadamard 
matrices, which are what simplex codes come from.

 	-thomas