The Math
object contains static properties and methods for mathematically dealing with numbers or providing mathematical constants (Math.PI;
). This object is built into JavaScript, as opposed to being based on a Math()
constructor that creates math instances.
It might seem odd that Math
starts with a capitalized letter since you do not instantiate an instance of a Math
object. Do not be thrown off by this. Simply be aware that JavaScript sets this object up for you.
Math
Properties and Methods
The Math
object has the following properties and methods:
Properties (Math.PI;
):
Methods (Math.random();
):
abs()
acos()
asin()
atan()
atan2()
ceil()
cos()
exp()
floor()
log()
max()
min()
pow()
random()
round()
sin()
sqrt()
tan()
Math
Is Not a Constructor Function
The Math
object is unlike the other built-in objects that are instantiated. Math
is a one-off object created to house static properties and methods, ready to be used when dealing with numbers. Just remember, there is no way to create an instance of Math
, as there is no constructor.
Math
Has Constants You Cannot Augment or Mutate
Many of the Math
properties are constants that cannot be mutated. Since this is a departure from the mutable nature of JavaScript, these properties are in all caps (Math.PI;
). Do not confuse these property constants for constructor functions due to the capitalization of their first letter. They are simply object properties that cannot be changed.
User-defined constants are not possible in JavaScript 1.5, ECMA-262, Edition 3.
Conclusion
You should now have a few new tools that you can use for any math related tasks with JavaScript.
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