The "Math" Object Type - The Math Container

This section provides a quick description and a tutorial example script on the 'Math' built-in object type. There is only one default 'Math' object called 'Math' that holds all math properties and functions.

The "Math" object type is a special built-in object type, that is used by the host environment to create a single "Math" object as a container for many mathematics related properties and functions. It has the following main features:

Here is a tutorial example script showing some of the those features:

// Math_Object_Type.js
// Copyright (c) 2013 by Dr. Herong Yang, herongyang.com

   // Creating your own "Math" objects is not allowed
   // var myObject = new Math();

   // Checking this object
   println("\nAbout this \"Math\":");
   println("   Type = "+(typeof Math));
   println("   Instance Of Object: "+(Math instanceof Object));
   println("   Instance Of Function: "+(Math instanceof Function));
   println("   Instance Of Math: "+(Math instanceof Math));
   println("   toString(): "+Math.toString());

   println("\n\"Math\" value properties:");
      println("   Math.E = "+Math.E);
      println("   Math.PI = "+Math.PI);
      println("   Math.SQRT2 = "+Math.SQRT2);

   println("\nCalling \"Math\" function properties - methods:");
      println("   Math.sqrt(2) = "+Math.sqrt(2));
      println("   Math.sin(Math.PI) = "+Math.sin(Math.PI));
      println("   Math.abs(-17.78) = "+Math.abs(-17.78));
      println("   Math.ceil(-17.78) = "+Math.ceil(-17.78));
      println("   Math.floor(-17.78) = "+Math.floor(-17.78));
      println("   Math.round(-17.78) = "+Math.round(-17.78));
      println("   Math.random() = "+Math.random());

If you run this script with "jrunscript", you will get:

About this "Math":
   Type = object
   Instance Of Object: true
   Instance Of Function: false
   Instance Of Math: false
   toString(): [object Math]

"Math" value properties:
   Math.E = 2.718281828459045
   Math.PI = 3.141592653589793
   Math.SQRT2 = 1.4142135623730951

Calling "Math" function properties - methods:
   Math.sqrt(2) = 1.4142135623730951
   Math.sin(Math.PI) = 1.2246467991473532e-16
   Math.abs(-17.78) = 17.78
   Math.ceil(-17.78) = -17
   Math.floor(-17.78) = -18
   Math.round(-17.78) = -18
   Math.random() = 0.4715524330340368

Now we know how to use the "Math" object.

Read other "Math" related chapters to see more tutorial examples.

Table of Contents

 About This Book

 Introduction to JavaScript

 ECMAScript Language Specification and JavaScript Dialects

 Data Types, Variables and Expressions

 Flow Control Statements

 Creating, Accessing, and Manipulating Arrays

 Defining and Calling Functions

 Web Browser Supporting JavaScript

 Server-Side and Client-Side Web Scripting

 Introduction to Objects

 Defining Your Own Object Types

 Inheritance of Properties and Methods through the Prototype Object Chain

 'jrunscript' - JavaScript Shell Command from JDK

 Using Functions as "Function" Objects

Introduction to Built-in Object Types

 Overview of Built-in Object Types

 The "Object" Object Type - The Root Object Type

 The "Global" Object Type - The Invisible Global Container

 Global Properties and Functions Defined in ECMAScript

 Global Properties and Functions Provided by "jrunscript"

 The "Function" Object Type - Functions Are Objects

 The "Array" Object Type - Arrays Are Objects

 The "String" Object Type - Not Equal to String Primitive Type

 The "Boolean" Object Type - Wrapping Boolean Values into Objects

 The "Number" Object Type - Not Equal to Number Primitive Type

 The "Date" Object Type - Managing Dates and Times

 The "RegExp" Object Type - Regular Expression Patterns

 The "Error" Object Type - Runtime Exceptions

The "Math" Object Type - The Math Container

 W3C's Document Object Model (DOM) Specifications

 References

 PDF Printing Version