Thanks for the translation :) It makes more sense to me now!

Since finding out that the groebner basis approach is doomed, iv
actually managed to find another method which doesnt use them. Looks
like I might just get my PhD after all....

Thanks,
Dan

On Jun 25, 11:38 am, Martin Albrecht <[EMAIL PROTECTED]>
wrote:
> On Wednesday 25 June 2008, Daniel Loughran wrote:
>
> > thanks for the help dudes,
>
> > Although Im sorry Michael but I dont really understand any of your
> > last paragraph (rather Jargon heavy!) Swap? Bad Locality? FGB? F4? Are
> > you saying that I might be able to solve my problem using singular?
>
> Hi there,
>
> you are using Singular (this is what does the heavy lifting behind the
> scenes).
>
> Jargon buster:
>
> Swap: Gröbner basis computations are exponential in time and memory on
> average. Thus, if you "increase" it only slightly your memory usage might
> increase a lot, you run out of fast RAM and hit the slow swap.
>
> Locality: An algorithm which uses say 20GB of data but loads e.g. 200MB at a
> time and computes 1 minute with those has better locality than a computation
> which jumps around in those 20GB all the time. Since these 20GB don't fit in
> RAM on most computers the later has to ask Swap (harddisk) quite often which
> is ~ 100 times slower than RAM if not more.
>
> FGB: A program by Jean-Charles Faugere which implements Buchberger's algorithm
> and F4:http://fgbrs.lip6.fr/jcf/
>
> F4: An algorithm developed by Jean-Charles Faugere to compute Gröbner bases.
> It reduces several pairs at once by using linear algebra which makes it quite
> efficient but memory hungry. F4 is implemented in FGB and Magma. Singular
> (and thus Sage) has "a variant" of F4 called SlimGB which also does
> multi-reduction but without linear algebra. See I.groebner_basis? for details
> if I is your ideal.
>
> Hope that helps,
> Cheers,
> Martin
>
> --
> name: Martin Albrecht
> _pgp:http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
> _www:http://www.informatik.uni-bremen.de/~malb
> _jab: [EMAIL PROTECTED]
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