From: andrew_queisser@... (andrew queisser)
Date: 2002-09-10T07:32:38+09:00
Subject: How best to histogram words?

I want to count the occurrence of specific words. In the past I've
used a hash as shown below. Is there a better way? I don't know which
words will occur, otherwise I'd just preinitialize the hash to all
zeros.

Thanks, Andrew

foo = Hash.new
bar = Hash.new
while l = gets
  l.split.each { |w|
    # option 1: try to increment cell, catch error
    begin
      foo[w] += 1
    rescue NameError
      foo[w] = 1
    end

    # option 2: initialize on first use
    bar[w] = 0 if !bar[w]
    bar[w] += 1
  }
end
puts foo
puts bar