From: 7stud -- <bbxx789_05ss@...>
Date: 2008-01-23T10:48:58+09:00
Subject: Re: How to improve this code?

Jair Rillo Junior wrote:
> Hi guys,
> I am new in the Ruby world, I am coming from Java, and I would like to
> "think " in Ruby instead Java.
> 
> I did a code to read a CSV file (separated by comma), organize the
> values and print the output.
> 
> Basically the CSV looks like this:
> bla@bla.com,value1
> bla@bla.com,value2
> bla@bla.com,value3
> bla@bla.com,value4
> ruby@ruby.br,value1
> ruby@ruby.br,value2
> 
> the output should be in two lines
> bla@bla.com,value1,value2,value3,value4
> ruby@ruby.br,value1,value
> 
> My initial thought was store the values into a Hash object, where the
> KEY is the email (column a) and the value is an Array containing the
> values (column b).
> Going through all lines, test if the email address already exists in the
> Hash, if so update the Array, otherwise create a new entry into the
> Hash.
> 
> The code following below:
> 
> h = Hash.new
> File.open("Sector_brand.csv").each_line do |lines|
>   values = lines.split(",")
>   email = values[0]
>   content = values[1]
>   if h.key?(email)
>     l = h[email]
>     l.push content
>     h[email] = l
>   else
>     l = [content]
>     h[email] = l
>   end
> end
> 
> I didn't put the code to print the Hash. Also I didn't create the code
> above in a class because it is just a test.
> 
> Well guys, does anyone could see my code and give comments? How the code
> above could be improved?
> 
> Thanks in advice.
> 
> Junior

Try this:

h = Hash.new do |hash, key|
  hash[key] = []
end

IO.foreach('data.txt') do |line|
  data = line.chomp.split(',')
  h[data[0]] << data[1]
end

p h

--output:--
{"ruby@ruby.br"=>["value1", "value2"], "bla@bla.com"=>["value1", 
"value2", "value3", "value4"]}
-- 
Posted via http://www.ruby-forum.com/.