Ingo Schwarze <schwa...@usta.de> wrote:
> Alexander Nasonov wrote on Fri, Dec 20, 2019 at 08:33:40PM +0000:
> > j...@bitminer.ca wrote:
>
> >> Clarify that drand48 returns values not including 1.0.
>
> > It's not clear from the documentation whether drand48 can generate
> > a denormal number. If it can't, you can exclude 0.0 because it's
> > a denormal ;-)
>
> Looking at our code in lib/libc/stdlib/drand48.c, i conclude that
> drand48(3) does return 0.0 with a probability of 2^-48.
>
> More generally, the function returns a uniform distribution of
> numbers from the set {2^-48 * n | n integer and 0 <= n < 2^48}.
>
> Talking about loading bits into the mantissa and adjusting the
> exponent feels mildly confusing, given that the distribution is
> simply uniform over a fixed finite set. I'm not sending a patch
> because i never looked at how floating point representation works
> internally, so i would likely only make matters worse.
In which mode, the deterministic mode or the actual random mode? :)
