Re: random(x) for x in [2^31, 2^32)

[Karim BELABAS <Karim.Belabas@math.u-psud.fr>]

On Fri, 17 Oct 2003, Phil Carmody wrote:
> while(1,m=random(2^31);print(m))
> 4242106392
[...]
> all too high
>
>
> while(1,print(random(2^32-1)))
> 0
[...]
> all suspiciously low.
>
> 2.2.6 on x86.
>
> My alpha doesn't seem to have problems either there or at the
> 2^63..2^64-1 cutoff (assuming that 64-bits is a significant unit for an
> alpha), but it's running only 2.1.5, alas.

Diagnosed and fixed by Brian Gladman: there was a (unsigned / signed) long
confusion in mp_indep.c:randomi().

Fixed in CVS.

    Karim.
-- 
Karim Belabas                     Tel: (+33) (0)1 69 15 57 48
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