usage: ruby ltsv2csv.rb --file hoge.ltsv

ltsv2csv.rb

#!/usr/bin/ruby
require 'optparse'

separator = ","
source = false

ARGV.clone.options do |opts|
  opts.banner = "Usage: #{$0} [options]"
  opts.on('-f', '--file=/path/to/file', String, 'Source file'){|v|
    source = v
  }
  opts.on('-t', '--tab', 'Use tab for separator'){
    separator = "\t"
  }
  opts.on('-h', '--help', 'Show this help message.'){ puts opts; exit }

  opts.order! { |o| file ||= o } rescue retry
end

io = source ? open(source, 'r') : STDIN
labels = Array.new();
rows = Array.new();

while ltsv = io.gets
  row = Array.new();
  ltsv.chomp.split("\t").each do |data|
    if labels.index(data.split(":")[0]) == nil then
      labels << data.split(":")[0]
    end
    row[labels.index(data.split(":")[0])] = data.split(":")[1]
  end
  rows << row.join(separator)
end

puts labels.join(separator)
puts rows