Ruby | Date ajd() method Last Updated : 09 Jan, 2020 Comments Improve Suggest changes Like Article Like Report Date#ajd() is a Date class method which returns the astronomical Julian day number. Syntax: Date.ajd() Parameter: Date values Return: the astronomical Julian day number. Example #1 : Ruby 1=1 # Ruby code for Date.ajd() method # loading date require 'date' # declaring Date a = Date.new(2019, 1, 1) # declaring Date b = Date.jd(2452004) # declaring Date c = Date.ordinal(2019, 12) # Date puts "Date a : #{a}\n\n" puts "Date b : #{b}\n\n" puts "Date c : #{c}\n\n\n\n" # ajd form puts "Date a ajd form : #{a.ajd}\n\n" puts "Date b ajd form : #{b.ajd}\n\n" puts "Date c ajd form : #{c.ajd}\n\n" Output : Date a : 2019-01-01 Date b : 2001-04-04 Date c : 2019-01-12 Date a ajd form : 4916969/2 Date b ajd form : 4904007/2 Date c ajd form : 4916991/2 Example #2 : Ruby # Ruby code for Date.ajd() method # loading date require 'date' # declaring Date a = Date.parse('2019-01-01') # declaring Date b = Date.strptime('03-12-2019', '%d-%m-%Y') # declaring Date c = Date.commercial(2019, 5, 6) # Date puts "Date a : #{a}\n\n" puts "Date b : #{b}\n\n" puts "Date c : #{c}\n\n\n\n" # ajd form puts "Date a ajd form : #{a.ajd}\n\n" puts "Date b ajd form : #{b.ajd}\n\n" puts "Date c ajd form : #{c.ajd}\n\n" Output : Date a : 2019-01-01 Date b : 2019-12-03 Date c : 2019-02-02 Date a ajd form : 4916969/2 Date b ajd form : 4917641/2 Date c ajd form : 4917033/2 Comment More infoAdvertise with us Next Article Ruby For Beginners K Kirti_Mangal Follow Improve Article Tags : Ruby Ruby-Methods Ruby Date-class Similar Reads Ruby Programming Language Ruby is a dynamic, reflective, object-oriented, general-purpose programming language. 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Technically in encap 2 min read Ruby MixinsBefore studying about Ruby Mixins, we should have the knowledge about Object Oriented Concepts. If we don't, go through Object Oriented Concepts in Ruby . When a class can inherit features from more than one parent class, the class is supposed to have multiple inheritance. But Ruby does not support 3 min read Instance Variables in RubyThere are four different types of variables in Ruby- Local variables, Instance variables, Class variables and Global variables. An instance variable in ruby has a name starting with @ symbol, and its content is restricted to whatever the object itself refers to. Two separate objects, even though the 3 min read Data Abstraction in RubyThe idea of representing significant details and hiding details of functionality is called data abstraction. The interface and the implementation are isolated by this programming technique. Data abstraction is one of the object oriented programming features as well. 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