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Re: can `shuffle-vector' be moved?

From: Thierry Volpiatto
Subject: Re: can `shuffle-vector' be moved?
Date: Fri, 13 May 2011 19:13:08 +0200
User-agent: Gnus/5.110018 (No Gnus v0.18) Emacs/24.0.50 (gnu/linux)

Stefan Monnier <address@hidden> writes:

>>> I don't know where it should live, but cookie1.el doesn't seem like the
>>> right place.
>>> It should be documented in "(elisp) Vector Functions" as well.
>>> Let me know if I should do this, please.
>>> Also this loop call from Pascal Bourguignon is a nice CL alternative to
>>> `shuffle-vector', though it uses the same algorithm:
>>> (defun shuffle (vector)
>>> "Re-orders randomly the vector."
>>> (loop
>>> for i from (1-  (length vector)) downto 1
>>> do (rotatef (aref vector i) (aref vector (random i)))))
>> Nice.
>> Why is this limited to vectors? with elt it could work also with lists.
> Its algorithmic performance on lists would be poor (O(N²)).
> You want a different algorithm for lists.
Ok. Thanks.

A+ Thierry
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