Re: primpoly

[David Bateman]

address@hidden wrote:
> Hi,
>  
> the function primpoly in the octave-forge communications toolbox seems 
> to behave as follows
>  
> primpoly(M, 'all') gives all primitive polynomials over GF(2^M) with 
> order less than or equal to M. 
>  
> How does one search for primitive polynomials over GF(2^M) with orders 
> greater than M?
>  
> cheers,
>  
> Aaron.

primpoly(M,'all') returns "all" primitive polynomials of order M rather 
than all primitive polynomials less than or equal to M.. Returning all 
the primitive polynomials with an order greater than M doesn't makes 
sense to a few reasons..

1) There are an infinite number of primitive polynomials with an order 
greater than M
2) The octave code can only handle M less than or equal to 16 as bigger 
than that and the memory requirements explode
3) The code to search for the primitive polynomials is a comprehensive 
search and so as M grows it gets slower

If you want primitive polynomials with orders between N and M just call 
primpoly repeatedly

D.


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