[alexandria-devel] Bug in shuffle (sequences.lisp)

[Jianshi Huang]

Or

(loop for i from (- end 1) downto start
      do (rotatef (aref sequence i) (aref sequence (+ start (random (-
(1+ i) start))))))

if you want a downward version.


On Tue, Nov 8, 2011 at 6:27 PM, Jianshi Huang <jianshi.huang at gmail.com> wrote:
> (loop for i from (- end 1) downto start      do (rotatef (aref
> sequence i) (aref sequence (random (+ i 1)))))
> should be
>
> (loop for i from start below end      do (rotatef (aref sequence i)
> (aref sequence (+ i (random (- end i))))))
> otherwise the element selected won't be bound by [start, end),
>
> similar bug in the sequence typed version
> Cheers,
> --
> 黄　澗石 (Jianshi Huang)
> http://huangjs.net/
>



-- 
黄　澗石 (Jianshi Huang)
http://huangjs.net/