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Re: BigInteger.modInverse() fix


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On Monday 16 December 2002 17:43, Per Bothner wrote:
> Tom Tromey wrote:
> >>>>>>"Per" == Per Bothner <per@bothner.com> writes:
> >
> > Per> Would it make sense to do:
> > Per>            rem = rem.canonicalize();
> > Per>            quot = quot.canonicalize();
> > Per> It probably doesn't matter.
> >
> > Are rem and quot guaranteed not to be small?...
>
> Not necessarirly.  I don't think canonicaliztion of small
> integers is required for correctness, just (space) effiency...

...and speed, for some numerical algorithms where modulo 2**32 is 
enough.


> > Per> Instead of allocating a BigInteger at each level of
> > Per> recursion, maybe you could modify euclidInv to:
> >
> > The code already has a FIXME about its inefficient use of memory. 
> > So I think making this change isn't a requirement for the patch. 
> > OTOH, if Mark or Raif want to do it, that would be great.

see later.


> I didn't mean it as a requirement - only a suggestion.

i'd like to spend sometime over the BigInteger code to see if/how we can 
improve its effeciency, and in the process fix the FIXME, etc.  
unfortunately it's not gonna be soon --it shouldnt be too long 
neither-- since i'd like to stabilise GNU Crypto first.

so... i'll raise my hand for this task, unless somebody else beats me to 
it.


cheers;
rsn
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