Ruby | Date << function Last Updated : 09 Jan, 2020 Comments Improve Suggest changes Like Article Like Report Date#<<() is a Date class method which returns the date object pointing 'n' (numeric value argument) months before self. Syntax: Date.<<() Parameter: Date values Return: date object pointing n months before self. The argument n should be a numeric value. Example #1 : Ruby 1=1 # Ruby code for Date.<<() 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" # << form puts "Date a << form : #{a << Rational(3, 2)}\n\n" puts "Date b << form : #{b << Rational(10, 2)}\n\n" puts "Date c << form : #{c << Rational(10, 4)}\n\n" Output : Date a : 2019-01-01 Date b : 2001-04-04 Date c : 2019-01-12 Date a << form : 2018-11-01 Date b << form : 2000-11-04 Date c << form : 2018-10-12 Example #2 : Ruby # Ruby code for Date.<<() 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" # << form puts "Date a << form : #{a << Rational(3, 2)}\n\n" puts "Date b << form : #{b << Rational(10, 2)}\n\n" puts "Date c << form : #{c << Rational(10, 4)}\n\n" Output : Date a : 2019-01-01 Date b : 2019-12-03 Date c : 2019-02-02 Date a << form : 2018-11-01 Date b << form : 2019-07-03 Date c << form : 2018-11-02 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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It helps us to get the current time and date according to our system configurations. It also gives us the components of a date and time and also to format time and date. The date is the day of a month or year that is represented by a nu 3 min read OOP ConceptsObject-Oriented Programming in Ruby | Set 1When we say object-oriented programming, we mean that our code is centered on objects. Objects are real-life instances that are classified into various types. Let’s take an example to understand this better. If we consider a rose as an object, then the class of the rose will be flower. A class is li 9 min read Object Oriented Programming in Ruby | Set-2Prerequisite: Object Oriented Programming in Ruby | Set-1 Inheritance Inheritance is one of the solid fundamental characteristics of object-oriented programming. sometimes we might need certain features of a class to be replicated into another class. Instead of creating that attribute again, we can 8 min read Ruby | Class & ObjectRuby is an ideal object-oriented programming language. The features of an object-oriented programming language include data encapsulation, polymorphism, inheritance, data abstraction, operator overloading etc. In object-oriented programming classes and objects plays an important role. A class is a b 4 min read Private Classes in RubyThe concept of private, protected and public methods in Ruby is a bit different than it other languages like Java. In Ruby, it is all about which class the person is calling, as classes are objects in ruby. Private Class When a constant is declared private in Ruby, it means this constant can never b 3 min read Freezing Objects | RubyAny object can be frozen by invoking Object#freeze. 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There are m 3 min read Ruby | ConstructorsA constructor is a special method of the class that gets automatically invoked whenever an instance of the class is created. Like methods, a constructor may also contain a group of instructions or a method that will execute at the time of object creation. Important points to remember about Construct 2 min read Ruby | Access ControlAccess control is a very important part of the object-oriented programming language which is used to restrict the visibility of methods and member fields to protect data from the accidental modification. In terms of access control, Ruby is different from all other Object Oriented Programming languag 8 min read Ruby | EncapsulationEncapsulation is defined as the wrapping up of data under a single unit. It is the mechanism that binds together code and the data it manipulates. In a different way, encapsulation is a protective shield that prevents the data from being accessed by the code outside this shield. 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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Here, error means an unwanted or unexpected event, which occurs during the execution of a program, i.e. at run time, that disrupts the normal flow of the program's instructions. So these types of 6 min read Catch and Throw Exception In RubyAn exception is an object of class Exception or a child of that class. Exceptions occurs when the program reaches a state in its execution that's not defined. Now the program does not know what to do so it raises an exception. This can be done automatically by Ruby or manually. Catch and Throw is si 3 min read Raising Exceptions in RubyAn exception is an unwanted or unexpected event, which occurs during the execution of a program i.e at runtime, that disrupts the normal flow of the program’s instructions. As we know, the code enclosed between begin and end block is totally secured for handling Exceptions and the rescue block tells 4 min read Ruby | Exception Handling in Threads | Set - 1Threads can also contain exceptions. 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Ruby regex can 3 min read Ruby Search and Replacesub and gsub string methods that use regular expressions, and their in-place variants are sub! and gsub!. The sub & sub! replaces the first occurrence of the pattern and gsub & gsub! replaces all occurrences. All of these methods perform a search-and-replace operation using a Regexp pattern. sub! an 2 min read Ruby ClassesRuby | Float ClassIn Ruby, Float class is a subclass of Numeric class. The objects of the Float class represents real numbers using the native architecture's double- precision floating-point representation. Public Instance Methods Arithmetic Operations: This method perform various arithmetic operations on float. Addi 7 min read Ruby | Integer ClassIn Ruby, Integer class is the basis for the two concrete classes that hold whole numbers. These concrete classes are Bignum and Fixnum. Fixnum holds integer values that are shown in the native machine word, whereas Bignum holds the integer value outside the range of Fixnum. 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Class Methods 1. mkdir : This method is used to create a new directo 3 min read Ruby | MatchData ClassIn Ruby, all the pattern matching is done with the help of special variable $~. All the pattern matches will set the $~ to a MatchData that contains the information about the match. The MatchData objects are returned by the Regexp#match and Regexp.last_match methods. The MatchData objects enclosed a 4 min read Ruby ModuleRuby | ModuleA Module is a collection of methods, constants, and class variables. Modules are defined as a class, but with the module keyword not with class keyword. Important Points about Modules: You cannot inherit modules or you can't create a subclass of a module. Objects cannot be created from a module. Mod 4 min read Ruby | Comparable ModuleIn Ruby, the mixin of Comparable is used by the class whose objects may be ordered. The class must be defined using an operator which compare the receiver against another object. It will return -1, 0, and 1 depending upon the receiver. If the receiver is less than another object, then it returns -1, 3 min read Ruby | Math ModuleIn Ruby, Modules are defined as a collection of methods, classes, and constants together. Math module consists of the module methods for basic trigonometric and transcendental functions. Module ConstantsNameDescriptionEDefine the value of base of natural logarithm e.PIDefine the value of π. Example: 4 min read Include v/s Extend in RubyInclude is used to importing module code. Ruby will throw an error when we try to access the methods of import module with the class directly because it gets imported as a subclass for the superclass. So, the only way is to access it through the instance of the class. Extend is also used to importin 2 min read Like