[CLN-list] multivariate factorization (ginac/ginsh)

[Joerg Arndt]

* Jens Vollinga <jensv at nikhef.nl> [Feb 21. 2010 14:00]:
> Hi Jörg,
> 
> Am 21.02.2010 08:59, schrieb Joerg Arndt:
> >[could someone please forward to ginac-devel, I am
> >  not subscribed there]
> 
> I am also reading cln-list :-)

Good!


> 
> ># but it appears to do multivariate factorization as well:
> 
> yes it does.

Note that doc should be updated accordingly.


> 
> ># The following seems to take forever:
> >
> >>t;
> >-E20^16*E4^8*E5^8*E1^16*q^4-(E10^24-E20^8*E5^16)*E4^16*E1^8+E2^24*E20^16*E5^8*q^4
> >>factor(t);
> >
> ># ctrl-C
> >  ginsh  815.46s user 3.39s system 94% cpu 14:26.22 total
> >
> >
> >Is the latter a huge-ish task or does ginac have a
> >performance issue here?
> 
> I ran the example and I get an exception! So, it seems there is a
> bug somewhere. I'll have a look at it.

Please keep me in the loop.
Also it appears sage is using ginac, so
they should be notified when this is fixed.


> 
> Regards,
> Jens


Thanks for the prompt reply!

cheers,    jj