From: Ken Bloom <kbloom@...>
Date: 2007-07-11T22:20:20+09:00
Subject: Re: Repacking an array of arrays

On Tue, 10 Jul 2007 12:00:47 +0900, Kaps Lok wrote:

> Is there an elegant (maybe a one-liner) for repacking:
> 
> [[1, 4, 7, 10, 13], [2, 5, 8, 11, 14], [3, 6, 9, 12, 15]]
> 
> to?
> 
> [[1, 4, 7], [10, 13, 2], [5, 8, 11], [14, 3, 6], [9, 12, 15]]
> 
> So rather than having 3 arrays each with 5 elements, I get five arrays
> of 3 elements each...
> 
> the only way I can see to do this is by looping the array, and creating
> new arrays.
> 
> Any help would be much appreciated.

require 'enumerator'
a=[[1, 4, 7, 10, 13], [2, 5, 8, 11, 14], [3, 6, 9, 12, 15]]
a.flatten.enum_slice(3).collect
 => [[1, 4, 7], [10, 13, 2], [5, 8, 11], [14, 3, 6], [9, 12, 15]]

-- 
Ken Bloom. PhD candidate. Linguistic Cognition Laboratory.
Department of Computer Science. Illinois Institute of Technology.
http://www.iit.edu/~kbloom1/