From: "David A. Black" <dblack@...>
Date: 2008-05-11T03:08:48+09:00
Subject: Re: Delete every other value in an array

Hi --

On Sun, 11 May 2008, 7stud -- wrote:

> Tim Conner wrote:
>> What is the best way to delete every other value in a ruby array?
>> e.g.
>> %w(a b c d e f g h i j k)
>>
>> becomes => [a c e g i k]
>>
>> thanks
>
>
> letters = ("a".."z").to_a
> last_index = letters.length - 1
>
> results = []
>
> 0.step(last_index, 2) do |i|
>  results << letters[i]
> end
>
> letters = results
> p letters

In Ruby 1.9 you can do:

   letters.values_at(*0.step(letters.size-1,2))

using the enumerator returned from step called without a block.


David

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