[Gcl-devel] Re: speed for primality

[Camm Maguire]

Greetings!

BTW, any pointers to the algorithm that uses this for a primality
check?  Wondering whether a primep belongs in gcl.

Take care,

Robert Boyer <address@hidden> writes:

> Here is how to get your primality test to really fly, I suspect.  Your
> function expt-a-to-i-mod-n is the key, I believe.  At least it is for RSA
> stuff.
> 
> 'mpz_powm' in Gnu GMP implements 'expt-a-to-i-mod-n'.  GCL already uses
> GMP for *many* bignum operations.  GMP claims it is the fastest bignum
> package.
> 
> It would probably only take Camm a very little amount of time to add powm
> (and many more GMP functions) to GCL.  It's on his to-do list, I believe.
> But it may be way down, I fear.  Or, we could learn a lot by spending
> weeks trying to learn how to do it ourselves, and I suspect it will all
> seem very easy when all is said and done.  Camm has already done the
> extremely hard work, interfacing GCL's heap and GMP's heap.
> 
> cf. ~/my-partition/gcl-2.7.0/gmp3/mpz/powm.c
> 
> Bob
> 
> 
> 

-- 
Camm Maguire                                            address@hidden
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