From: Robert Klemme <shortcutter@...>
Date: 2007-06-28T19:10:01+09:00
Subject: Re: Can i calculate the data number in array?

On 28.06.2007 10:44, Axel Etzold wrote:
> Dear Cool,
> 
> maybe this is what you want:
> 
> class Array
> 
> 
> 
>   def count
> 
>     k=Hash.new(0)
> 
>     self.each{ |x| k[x]+=1 }
> 
>     k
> 
>   end
> 
> 
> 
> end
> 
> 
> my_array = ["a", "a", "a", "b", "b", �c�, "c", "c","d", "d", "e"]
> my_array.count 
> 
> It gives you a Hash, though, and the numbers are Integers,
> not Strings, but this seems more reasonable :)

Yes, I'd agree.  Having tuples as return value is better because then 
you maintain relationship between items and item count.

Btw, thanks for leaving the inject solution to me. :-)

irb(main):005:0> a = %w{a a a b b c c c d d e}
=> ["a", "a", "a", "b", "b", "c", "c", "c", "d", "d", "e"]
irb(main):006:0> a.inject(Hash.new(0)) {|h,x| h[x]+=1; h}
=> {"a"=>3, "b"=>2, "c"=>3, "d"=>2, "e"=>1}
irb(main):007:0> a.inject(Hash.new(0)) {|h,x| h[x]+=1; h}.sort
=> [["a", 3], ["b", 2], ["c", 3], ["d", 2], ["e", 1]]

Kind regards

	robert