meta_eot.rb

class Eot

  attr_accessor :date, :lat, :lng, :attributes
   
  def initialize attributes
    @attributes = []		 
    attributes.each_key do |k|
      self.send("#{k}=", attributes[k])
      @attributes << attributes[k]
    end   
  end
		
  def self.new_method name
    send(:define_method, name) {yield}
  end
end	

require 'date'
params = {:date => DateTime.now.to_time.utc.to_datetime.to_s,
          :time => DateTime.now.to_time.utc.to_datetime.day_fraction,
          :lat => 41.5,
          :lng => -88.930
         }
								
eot = Eot.new(params)

ajd = Eot.new_method("ajd") {DateTime.parse(eot.attributes[0]).ajd.to_f + eot.attributes[1]}
jd = Eot.new_method("jd") {DateTime.parse(eot.attributes[0]).jd.to_f}
p ajd.call
p jd.call