gistfile1.rb

class Output <
  Struct.new(:name, :price)
end

unless ARGV.length == 1
  puts "Wrong number of Arguments"
  puts "Usage: ruby #{File.basename(__FILE__)} InputFile.tsv"
  exit
end

# get the input filename from the command line
input_file = ARGV[0]

# define an array to hold the Output records
arr = Array.new

#make header indices global
name_index = ""
price_index = ""

#open file
f = File.open(input_file, "r")


#loop through file
f.each_with_index { |line, i|

  #get indeces on first line
  if(i==0) then
    headers = line.split("\t")

    #strip newline character off last column
    last_index =  headers.length - 1
    headers[last_index] = headers.last.strip

    #get indexes
    name_index = headers.index("Name")
    price_index = headers.index("Price")
  end

  #skip first line and lines beginning with a hash
  next if i == 0
  if line[0] == "#"
    words = line.split("\t")
    puts "WARNING: #{words[name_index]} this line should be skipped #{words[price_index]}"
    next
  end

  words = line.split("\t")
  p = Output.new
  p.name = words[name_index]
  p.price = words[price_index].to_f
  arr.push(p)
}

# sort the data by the price field
arr.sort! { |a,b| a.price <=> b.price }

# print out all the sorted records
arr.each { |p|
  puts p.name + "\t" + p.price.to_s + "\n"
}