Bill Allombert on Wed, 14 May 2008 19:53:40 +0200

[Date Prev] [Date Next] [Thread Prev] [Thread Next] [Date Index] [Thread Index]

Re: bnfinit perhaps getting stuck?

On Tue, May 13, 2008 at 03:52:12PM +0000, Phil Carmody wrote:
> I can't say I know what is going on in the internals of bnfinit, but after having a calculation need a brutal ^C-ing after running for over a week, I decided to re-run it  with debugging on.
> ... and apparently it just sits there doing variations on those last few dozen or so lines ...
> """
> It's still running, just on the offchance that it kicks into a different phase. (Logs are available on request, they'll be 10MB quite soon, and growing quickly.)
> Is the algorithm guaranteed to terminate that phase, do you know, or it it worrying that bnfinit has apparently got stuck in a loop of endless variations that it apparently can't break out of?

Your polynomial is huge by bnfinit standard. Consider that I just
finished to compute bnfinit(x^31-31) and that took 109h after I applied
various patches to speed it up. 

You are using the stable version. Due to several improvement (in
particular 2.4.0F4 and the new LLL code) I would suggest you try 
the SVN version but actually, I should rather suggest you to give
up because I do not think this can finish.

Using \g1 is generally sufficient and keep the logs readable.
You can try
grep cglob <your log> 
or if this is too verbose
grep needed <your log>
to get a measure of progress.