------- Comment #6 from fxcoudert at gcc dot gnu dot org 2007-08-10 21:28
-------
(In reply to comment #5)
> Your attempt to randomize the seeds really isn't all that good because
> there is such a limited amount of entropy in year, month, day, and hour.
I do agree. There's no way I'm adding entropy just by a bijective function :)
> I have analyzed your algorthim closely enough, so what is the effect
> on someone who actually knows how to properly seed gfortran's PRNG.
> Are there any degenerate side effects?
There shouldn't be any side effect. What I'm doing is that I'm shuffling the
bytes between user-provided and internal KISS seed so that the first bytes of
the user seed end up distributed in both parts of the KISS seed (used for MSB
and LSB of the final random numbers); same thing for the last bytes. In that
way, whether the user seed has stronger first or last elements, it will not
reflect on the quality of the MSB/LSB generated.
So, since it's just shuffling bytes (and it's a bijective operation, of
course), I don't think I'm messing with any of the properties of the generator.
--
fxcoudert at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |fxcoudert at gcc dot gnu dot
|dot org |org
Status|NEW |ASSIGNED
Last reconfirmed|2007-07-28 13:07:22 |2007-08-10 21:28:07
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32812
