Karim Belabas on Sun, 10 Nov 2013 00:33:07 +0100


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Re: Large errors for eint()


* Jeroen Demeyer [2013-11-09 23:58]:
> On 2013-11-09 23:36, Karim Belabas wrote:
> >2) For veceint1, a documentation problem: the function is implemented to
> >ensure a bound on the *absolute* error. This is inconsistent with (most)
> >other transcendental functions, but corresponds to the main application
> >for us: computing L-functions via approximate functional equation. I
> >have just fixed the documentation.
> And can you say what is the absolute bound? Knowing there is an
> absolute bound but not knowing what the bound actually is, is not
> really that useful.

Same rule as for relative errors, except it is absolute now: 10^-n, where n is
* precision(x) if input x is inexact,
* realprecision otherwise

Cheers,

    K.B.
--
Karim Belabas, IMB (UMR 5251)  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-bordeaux1.fr/~kbelabas/
F-33405 Talence (France)       http://pari.math.u-bordeaux1.fr/  [PARI/GP]
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