Re: Question on finding a Riemann Zeta function zero for high values of s

[Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>]

On Wed, Oct 22, 2025 at 11:51:39PM +0200, Cohen Henri wrote:
> 
> Sorry, should have replied to list. In integrand_h0, replace line 309
> p1=gmul(expIxy(pmd,gsqr(zn),prec), by
> p1 = gmul(pmd, mulcxI(gsqr(zn))); p1r = greal(p1);
>  if (gcmpgs(mpabs(p1r), 2*prec2nbits(prec)) > 0) p1 = p1r;
>  p1 = gmul(gexp(p1, prec),
>  
> and declare p1r as a GEN. This is not good, but works here. It is to avoid an
> overflow in gsincos when taking the exponential of A+I*B where B is huge and
> A is huge negative or positive. The condition I wrote is ridiculous, but I don't know what
> to put else.

Thanks Henri!
I pushed this commit to a new branch henri-lfunlarge_overflow for future reference.
Cheers,
Bill.