this is now https://trac.sagemath.org/ticket/22961


On Monday, May 8, 2017 at 3:44:12 PM UTC+1, Peter Mueller wrote:
>
> The functions and their docs in codes.bounds.* still seem to be a mess (as 
> they have been since many years now). Here a few findings from a recent 
> attempt to use them in class:
>
> (1) If the code parameters are n = length, d = minimum distance, and q = 
> size of the alphabet, there seems to be no system about the order of the 
> arguments n, q, and d in these functions. For instance plotkin_upper_bound 
> and others expect the arguments in the order n, q, d, 
> while codesize_upper_bound and others expect the arguments in the order n, 
> d, q.
>
> (2) To make the inconsistencies in (1) even worse, the docs of many of 
> these functions *do not* tell the order of the arguments; instead one has 
> to look into the source code, or figure it out with small examples.
>
> (3) Even if  there is a doc which tells about the arguments, then it may 
> contain some other nonsense.  For instance hamming_upper_bound says that q 
> is the size of a field, while this bound actually holds for any finite 
> alphabet of size q.
>
> (4) Again, there seem to be wrong bounds. For instance, 
>  codesize_upper_bound(19,10,2) yields 8, while there are easy examples of 
> size 16, and it is known that there are even codes of size 20. Looking into 
> the source code reveals that codesize_upper_bound erroneously uses the 
> Griesmer bound, which works for linear codes only.
>
> I'm not sure how to fix the mess in (1) without breaking compatibility. 
> Maybe a solution could be to enhance these functions with keyword arguments.
>
> -- Peter Mueller
>

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