usd2rs.rb

#! /usr/bin/env ruby

# usd2rs AMOUNT - convert from US dollars to Indian Rupees
# Prints out Rupees in Lakhs & Crores as necessary

require 'open-uri'
LAKH, CRORE = 100_000, 10_000_000
dollars = (ARGV[0] || begin; printf "Dollars? "; gets.chomp; end).
          gsub(/,/, '').
          to_i
rate = open("http://www.google.com/finance/converter?a=1&from=USD&to=INR").
  read.
  scan(/class=bld>(\d*[.]?\d*)/)[0][0].to_f
rupees = dollars * rate
puts "(1 USD = Rs. #{rate})"
if rupees < LAKH
  puts "Rs. #{rupees}"
elsif rupees >= CRORE
  puts "Rs. #{rupees/CRORE} crores"
else
  puts "RS. #{rupees/LAKH} lakhs"
end