Re: Gnat Chat, Random Numbers in GNAT

[Keith Thompson <kst@cts.com>]

Ashley Deas Eachus <rieachus@earthlink.net> writes:
[...]
>       The second issue is that the number of possible values generated does
> not completely cover all of the representable values in [0.0 .. 1.0).
> Again the generator in gnat is much better than most in this area, but it
> only generates about 2**50 values, so there are small floating-point values
> near zero that cannot be generated.  Not a big worry, unless you are
> creating events with a very small probability of occurring.
[...]

If this is an issue, perhaps you can call Random twice for each random
number you need.  For example, if the Random function gives you a good
32-bit value, you can call it twice to construct a good 64-bit value.

(I'm probably missing some vital point here, so don't take my word for
it.)

-- 
Keith Thompson (The_Other_Keith) kst@cts.com  <http://www.ghoti.net/~kst>
San Diego Supercomputer Center           <*>  <http://www.sdsc.edu/~kst>
Welcome to the last year of the 20th century.