From: Robert Klemme <shortcutter@...>
Date: 2010-03-25T17:30:42+09:00
Subject: Re: hash problem

2010/3/25 Adam Nelreth <nelreth@gmail.com>:
> Hi
>
> I have small problem with adding data to hash table
>
> In loop I take some string and get IP address from it like this:
>
> ip =
> /(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)/.match(title)
>
> and now under ip variable I have my IP which I want to put in hash table
> and count if the same IP I will find in another step (loop)
>
> I create hash table
> test = Hash.new
> and put it in table
> test[ip] = 1
>
> But I don't know how to search table to find if the same ip is already
> in table and increase counter
>
> Could You tell me how to do this or give me just a clue how to figure
> this out ?

The usual idiom for counting is this:

counters = Hash.new 0
...
counters[ip] += 1

If you want to print sorted descending by count, you can do

counters.sort_by {|ip,cnt| -cnt}.each do |ip,cnt|
  printf "%6d %s\n", cnt, ip
end

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/