# usage: cat accumulated_number_data.ltsv | ruby calc_delta.rb

calc_delta.rb

#!/usr/bin/env ruby
# usage: cat accumulated_number_data.ltsv | ruby calc_delta.rb

class LtsvDataLine
  attr_accessor :data

  def initialize(line)
    @data = Hash.new
    line.split("\t").each{|packet|
      @data[packet.split(":")[0]] = packet.split(":")[1]
    }
  end

  def to_s
    s = ""
    @data.sort.each{|key, value|
      s = s + "#{key}:#{value}\t"
    }
    s
  end
end

previous_line = nil
while gets
  if previous_line.nil? then
    # do nothing

  else
    current_line = LtsvDataLine.new($_.chomp)
    current_line.data.each{|key, value|
      if key!="date" then
        if previous_line.data[key].nil? then
          current_line.data.delete(key)
        else
          current_line.data[key] = value.to_i - previous_line.data[key].to_i
        end
      end
    }
    puts sprintf("date:%s\t%s", current_line.data.delete("date"), current_line.to_s )
  end
  previous_line = LtsvDataLine.new($_.chomp)
end