[Python-Dev] a note in random.shuffle.__doc__ ...

Tim Peters tim.peters at gmail.com
Tue Jun 13 02:18:43 CEST 2006

[Raymond Hettinger]
> I think the note is still useful, but the "rather small" wording
> should be replaced by something most precise (such as the
> value of n=len(x) where n! > 2**19997).

Note that I already removed it, and I'm not putting it back.  The
period of W-H was "so short" you could get into trouble, based on
period alone, with a list of only 16 elements.  The Twister is so much
more capable in respect of both period and high-dimensional
equidistribution properties that I think anyone sophisticated enough
to _understand_ an accurate warning correctly would have no need to be
warned.  Everyone else would find it a mix of confusing and scary, to
no real end.

None of this is to say it couldn't be useful to have a digestible
introduction to issues raised by use of deterministic PRNGs.  But I
don't think that one note in one docstring is actually "better than
nothing" in that regard ;-)

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