Re: (BUG?) Erroneous I+R overflow in GP/PARI Version 2.0.18 (beta)

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

>  ?  exp(2*Pi*I*((9/2)/(3/35 + 3/35*I)))-1
>    ***   overflow in I+R
>  ?  exp(2*Pi*I*((9/2)/(3/35 + 3/35*I)))
>  %1 = 0.0000000000000000000000000000 + 4.263424501275723583926909456 E71*I

This is not a bug at all, the real part of %1 is 0E74, but the
precision is only 28 digits, so 0E74 can be any number between -1E46
and 1E46, so adding 1 is not meaningful.

So two thing can be done(or not !)

%1 should be printed 0E74 + 4.263424501275723583926909456 E71*I to
insist on the accuracy. It is already the case for negative exponents

? 1.-1
%14 = 0.E-28
? 100000.-100000
%16 = 0.E-24

Secondly, 0E74+1 should return 0E74, which is correct, but will
probably not lower the number of bug reports on this topic.

Bill.