From: Morton Goldberg <m_goldberg@...>
Date: 2006-07-20T17:29:55+09:00
Subject: Re: how to split an array in sub arrays of the same length

Although you could use Enumerator::each_slice as others have  
suggested, it might be simpler to augment Array with a partition  
function.

class Array

def partition(n, r=[])
    raise ArgumentError if n <= 0
    if n <= size then
       r << first(n)
       last(size -  n).partition(n, r)
    else
       r << self unless empty?
       return r
    end
end

end

p [ 1, 2, 3, 4, 5, 6, 7, 8 ].partition(1) => [[1], [2], [3], [4],  
[5], [6], [7], [8]]
p [ 1, 2, 3, 4, 5, 6, 7, 8 ].partition(3) => [[1, 2, 3], [4, 5, 6],  
[7, 8]]
p [ 1, 2, 3, 4, 5, 6, 7, 8 ].partition(4) => [[1, 2, 3, 4], [5, 6, 7,  
8]]
p [ 1, 2, 3, 4, 5, 6, 7, 8 ].partition(6) => [[1, 2, 3, 4, 5, 6], [7,  
8]]
p [ 1, 2, 3, 4, 5, 6, 7, 8 ].partition(8) => [[1, 2, 3, 4, 5, 6, 7, 8]]
p [ 1, 2, 3, 4, 5, 6, 7, 8 ].partition(10) => [[1, 2, 3, 4, 5, 6, 7, 8]]
p [ 1, 2, 3, 4, 5, 6, 7, 8 ].partition(-2) =>
      untitled text:6:in `partition': ArgumentError (ArgumentError)
	     from untitled text:24

Hope this is helps.
Regards, Morton

On Jul 20, 2006, at 2:55 AM, Paolo Bacchilega wrote:

> Hi,
>
> Is there a way to split an array in sub arrays of the same length,  
> that
> is :
>
> [ 1, 2, 3, 4, 5, 6, 7, 8 ].unknown_function(3)
>
> that returns:
>
> [ [1, 2, 3], [4, 5, 6], [7, 8] ]
>
>
> thanks in advance.