| Karim Belabas on Wed, 14 Jan 2004 21:37:32 +0100 |
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| Re: Zeta function bug? |
* Andrew John Walker <ajw01@uow.edu.au> [2004-01-07 02:19]:
> On Wed, 7 Jan 2004, Karim Belabas wrote:
>> * Andrew John Walker <ajw01@uow.edu.au> [2003-12-31 03:37]:
>>> Under pari Version 2.0.17 (beta)
>>> ? zeta(4.45+292532.0*I)
>>> %4 = 0.9628325946986762532107312785 - 0.007964269348872060270684500688*I
>>>
>>> Under pari Version 2.2.7 (alpha)
>>> (13:13) gp > zeta(4.45+292532.0*I)
>>> %77 = -1.519052693065775291998804237 E84 + 3.820179262621090164984728018
>>> E84*I
>>>
>>> Which (if any) of these is correct?
>>
>> Neither. It should be
>>
>> 0.9628325946986762532107312786 - 0.007964269348872060270684500689*I
>>
>> (OK, 2.0.17 is closer :-)
>>
>> The problem is due to an overflow in a C long multiplication (when more than
>> 46340 terms need to be summed to obtain the required precision). I have fixed
>> this in CVS.
>>
>> I can update the Windows binary if this problem is too much of an annoyance.
>>
> Thanks very much Karim. I'd appreciate if the Windows version
> could be updated whenever convenient.
I have just updated the Windows binary. Sorry for the delay !
Cheers,
Karim.
--
Karim Belabas Tel: (+33) (0)1 69 15 57 48
Dep. de Mathematiques, Bat. 425 Fax: (+33) (0)1 69 15 60 19
Universite Paris-Sud http://www.math.u-psud.fr/~belabas/
F-91405 Orsay (France) http://pari.math.u-bordeaux.fr/ [PARI/GP]