#!/usr/bin/env ruby
# encoding: UTF-8

require 'uri'
require 'open-uri'
require 'nokogiri'

class Btc_Balance
  def convert_btc_unit(balance)
    final = balance/100000000.0
    return final
  end

  def get_balance(addr)
    url = "https://blockchain.info/q/addressbalance/" << addr
    data = URI.parse(url).read
    doc = Nokogiri::HTML(data) 
    balance = doc.search('//html/body/p').text
    return balance 
  end         
end

  def main 
   btc_account = Btc_Balance.new
   addr = "your BTC address"
   balance = btc_account.get_balance(addr)
   final_balance = btc_account.convert_btc_unit(balance.to_i)
   puts "%.8f" % final_balance << " BTC" 
  end

main