Karim BELABAS on Mon, 1 Feb 1999 18:30:39 +0100 (MET) |
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Re: Primelimit |
> > I don't understand what you want to achieve by artificially lowering the > > number of primes available to some functions. Could you give more details ? > > If I understand Gerhard correct, some functions take primelimit not as > an advice about the number of available primes, but as a directive to > loop over these primes. > > Suppose I want to have a table of primes up to 1e9 (very easy with the > current PARI), say, to use forprime() with big primes. This may > significantly slow down the functions which loop over *all* existing > primes. I don't think there's any function like that. I'll check that. The only exception I can think of is factor(x, 0), and you can use factor(x, bound) to achieve exactly what you want [the default factor will only trial divides by the first 1000 primes or so before trying more elaborate stuff]. Karim. -- Karim Belabas email: Karim.Belabas@math.u-psud.fr Dep. de Mathematiques, Bat. 425 Universite Paris-Sud Tel: (00 33) 1 69 15 57 48 F-91405 Orsay (France) Fax: (00 33) 1 69 15 60 19 -- PARI/GP Home Page: http://hasse.mathematik.tu-muenchen.de/ntsw/pari/