From: Dan Zwell <dzwell@...>
Date: 2007-04-30T17:01:40+09:00
Subject: Re: sorting by rand?

Peter Seebach wrote:
>> Or perhaps because I 
>> have more method calls, as I made a method Array#randomize! (that calls 
>> Array#swap! n times)
> 
> That might well do it; method lookup is comparatively expensive, I
> think.
> 
> ... Of course, the entire thing is probably silly, in that I doubt most
> programs spend much time unsorting arrays.  I was mostly just curious
> about the question of what happens if you try to provide an un-fixed
> sort key.  For sort_by, they're cached; sort { rand <=> rand } might
> be unpredictable, though.
> 

That did it--I replaced calls to swap!() with three lines of code, and 
now my algorithm is faster on arrays with as little as 40 elements!

Dan