From: David Gustafson <daveg@...>
Date: 2012-05-01T01:17:46+09:00
Subject: Re: delete character from array

On Mon, Apr 30, 2012 at 8:33 AM, Ok Ok <lists@ruby-forum.com> wrote:
> Yes that was exactly it. I have one more question maybe you can help me
> with. Is there a way I could delete every 3rd letter in a string?
>
> --
> Posted via http://www.ruby-forum.com/.
>

If it was an array you were talking about the index of the letter you
want to delete would be (index + 1) % 3).

In pry or irb enter:

a = (1..20).to_a
a.select{|item| (item + 1) % 3 == 0}

So by that logic:

[8] pry(main)> b = "0123456789".bytes
=> #<Enumerator: ...>
[9] pry(main)> b.select{|item| (item + 1) % 3 == 0}
=> [50, 53, 56]
[10] pry(main)> b.select{|item| (item + 1) % 3 == 0}.each {|c| puts c.chr}
2
5
8
=> [50, 53, 56]


-- 
Doubt is not a pleasant condition, but certainty is absurd.
        -- Voltaire