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From: Ulrich Drepper <drepper@gmail.com>
Date: Sun, 13 Jul 2014 16:04:00 -0000
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Subject: Re: [PATCH] libstdc++: add uniform on sphere distribution
To: Paolo Carlini <paolo.carlini@oracle.com>
Cc: Ed Smith-Rowland <3dw4rd@verizon.net>, gcc-patches <gcc-patches@gcc.gnu.org>
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On Sun, Jul 13, 2014 at 11:43 AM, Paolo Carlini
<paolo.carlini@oracle.com> wrote:
> and I think: the normal distributions in x and y do have a non-trivial state
> (_M_saved, _M_saved_available) which, at any given moment, is different in x
> and y. Then the trivial inserter of x is called and the trivial extractor of
> y is called, nothing changes in y. I don't see how the following invocations
> of y(g) can produce the same sequence of numbers that would be produced by
> invocations of x(g).

Remember: we are talking about distributions, not RNGs.

The distribution has no parameters so given the same input (i.e.,
random byte sequences) it will create the same output all the time.