From: Philip Hallstrom <ruby@...>
Date: 2006-11-16T06:24:21+09:00
Subject: Re: Fully justified/center justified output

> Hi, how do I go about fully justifying/center justifying output text in ruby?
>
> I'm guessing I have to use sprintf but I can't seem to get it working 
> properly, not sure of the correct "%" characters (don't know the proper name 
> for them).

http://corelib.rubyonrails.org/classes/String.html#M001536

   str.center(integer, padstr) => new_str

If integer is greater than the length of str, returns a new String of 
length integer with str centered and padded with padstr; otherwise, 
returns str.

    "hello".center(4)         #=> "hello"
    "hello".center(20)        #=> "       hello        "
    "hello".center(20, '123') #=> "1231231hello12312312"