On Sun, Feb 02, 2003 at 12:04:22PM +0300, Andrey A. Chernov wrote: > Yes, first value correlation is there, but old formulae have even worse > effect "The random sequences do not vary much with the seed", as source > file comments and whole discussion about old RNG bad effects shown. I.e. > for different time+PID sequence, especially increased monotonically, like > in common practice, you'l got the same random sequence with old formulae > (which can't be called "works fine" because this fine work was the main > reason for change). So, returning to old formulae is not an option. > > The real problem is not in formulae, but in srand() funclion. This simple > patch can fix first value correlation, and I plan to commit it, if we all > agree. I not find better value for NSHUFF right now, but think > that something like 10 will be enough to fight corellation completely. > Some generating picture tests needed.
Another problem (noticed by tjr) is that once the sequence hits '0' it jumps to INT_MAX and stays there forever. For example, seeding with srand(0) produces nothing but INT_MAX from rand(). It looks like a lot more validation of this PRNG is needed. Kris
msg51493/pgp00000.pgp
Description: PGP signature
