| Karim Belabas on Mon, 09 Jan 2006 09:37:56 +0100 |
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| Re: length (lg) overflow |
* buromano@rcn.com [2006-01-06 21:52]:
> I'm getting this message; length (lg) overflow, using Dokchitser
> computel package and can't seem to find a reference for it. I image it
> relates to vector length.
PARI is trying to create a GEN object with length > 2^24 words [ e.g. a
vector with > 16777215 components ]
This is probably a sign of an inefficiency in computeL for your kind of
inputs, rather than a problem in PARI, but I would need a specific
testcase to be sure.
Hint: type 'trap' then trigger the problem and investigate within the
break loop the current values of the variables.
> Is there any way to increase something to get around this? Are there
> serious penalties?
The easiest is to use a 64 bit machine. Another possiblity (if the
porblem indeed comes from large vectors) is to draw inspiration from
http://www.math.u-bordeaux.fr/~belabas/pari/doc/faq.html#biggerlist
Cheers,
Karim.
--
Karim Belabas Tel: (+33) (0)5 40 00 26 17
Universite Bordeaux 1 Fax: (+33) (0)5 40 00 69 50
351, cours de la Liberation http://www.math.u-bordeaux.fr/~belabas/
F-33405 Talence (France) http://pari.math.u-bordeaux.fr/ [PARI/GP]