[Webkit-unassigned] [Bug 98586] Extend random precision to 53bits

bugzilla-daemon at webkit.org bugzilla-daemon at webkit.org
Sat Oct 6 11:44:10 PDT 2012


https://bugs.webkit.org/show_bug.cgi?id=98586





--- Comment #4 from Oliver Hunt <oliver at apple.com>  2012-10-06 11:44:40 PST ---

> I think it would be clearer just to shift 'a' right by 21 and then left by 32. It's not clear what you're trying to accomplish by removing bits from both values. For example, maybe you think that increases the randomness. But if each bit is random, that's not the case.


I you don't remove the overlapping bits then the likelihood of a bit in the overlapping region becomes much higher.

Here's your probability table for the overlapping region:
a  b  -> a | b
0  0          0
0  1          1
1  0          1
1  1          1

so probability of a given bit in the overlapping region being 1 is 0.75 rather than 0.5 as it should be

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.



More information about the webkit-unassigned mailing list