Re: The implementation should reward conciseness.

In APL it was (and is) well-known that the inverse of 
a permutation p can be computed as   (i.#p) p}p   
and is more efficient than /:p .  But watch this:

   p=: ?~ 1e5
   (/:p) -: (i.#p) p}p
1
   ts '/:p'
0.00611782 1.04922e6
   ts '(i.#p) p}p'
0.0112338 1.57389e6



----- Original Message -----
From: Roger Hui <[EMAIL PROTECTED]>
Date: Wednesday, November 5, 2008 0:05
Subject: Re: [Jprogramming] cut on length
To: Programming forum <[email protected]>

> It has been a long quest in APL/J to make
> x e. y  as fast as  1 x1}y1 .  The quest continues.
> 
> I must say that I like Brian Schott's solution (I.x)</.y 
> the best.  The implementation should reward concise
> solutions and I'll see if I can make that solution faster.
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