Re: [RFC][PATCH] Make cryptoapi non-optional?

Matt Mackall
2003-08-15T16:25:48Z

On Fri, Aug 15, 2003 at 09:30:03AM +0200, Andries Brouwer wrote:
> On Thu, Aug 14, 2003 at 06:17:13PM -0600, Val Henson wrote:
>
> > See Matt Mackall's earlier post on correlation, excerpted at the end
> > of this message. Basically, with two strings x and y, the entropy of
> > x alone or y alone is always greater than or equal to the entropy of x
> > xored with y.
> >
> > entropy(x) >= entropy(x xor y)
> > entropy(y) >= entropy(x xor y)
>
> Is this trolling? Are you serious?
> Try to put z = x xor y and apply your insight to the strings x and z.

Val left out the assumption that x and y are already perfectly
distributed, in and of themselves.

--
Matt Mackall : http://www.selenic.com : of or relating to the moon