JavaScript Math Object
The JavaScript Math object allows you to perform mathematical tasks on numbers.
Example:
Math.sin()
Math.sin(x) returns the sine (a value between -1 and 1) of the angle x (given in radians).
If you want to use degrees instead of radians, you have to convert degrees to radians:
Angle in radians = Angle in degrees x PI / 180.
Example:
Math.min() and Math.max()
Math.min() and Math.max() can be used to find the lowest or highest value in a list of arguments:
Example:
Math Constructor
Unlike other global objects, the Math object has no constructor. Methods and properties are static.
All methods and properties (constants) can be used without creating a Math object first.
Math Object Methods
Method Description
abs(x) Returns the absolute value of x
acos(x) Returns the arccosine of x, in radians
asin(x) Returns the arcsine of x, in radians
atan(x) Returns the between -PI/2 arctangent of x as a numeric value
and PI/2 radians
atan2(y, x) Returns the arctangent of the quotient of its arguments
ceil(x) Returns the value of x rounded up to its nearest integer
cos(x) Returns the cosine of x (x is in radians)
exp(x) Returns the value of Ex
floor(x) Returns the value of x rounded down to its nearest integer
log(x) Returns the natural logarithm (base E) of x
max(x, y, z, ..., n) Returns the number with the highest value
min(x, y, z, ..., n) Returns the number with the lowest value
pow(x, y) Returns the value of x to the power of y
random() Returns a random number between 0 and 1
round(x) Returns the value of x rounded to its nearest integer
sin(x) Returns the sine of x (x is in radians)
sqrt(x) Returns the square root of x
tan(x) Returns the tangent of an angle
JavaScript Random
Math.random()
Math.random() returns a random number between 0 (inclusive), and 1 (exclusive):
Math.random() always returns a number lower than 1.
Example:
JavaScript Random Integers
Math.random() used with Math.floor() can be used to return random integers.
Example:
JavaScript Booleans
A JavaScript Boolean represents one of two values: true or false.
Boolean Values
Very often, in programming, you will need a data type that can only have one of two values, like
YES / NO
ON / OFF
TRUE / FALSE
For this, JavaScript has a Boolean data type. It can only take the values true or false.
The Boolean() Function
You can use the Boolean() function to find out if an expression (or a variable) is true:
Example:
Comparisons and Conditions
The chapter JS Comparisons gives a full overview of comparison operators.
The chapter JS Conditions gives a full overview of conditional statements.
The Boolean value of an expression is the basis for all JavaScript comparisons and conditions.
Booleans Can be Objects
Normally JavaScript booleans are primitive values created from literals:
var x = false;
But booleans can also be defined as objects with the keyword new:
var y = new Boolean(false);
Example:
Note:- Do not create Boolean objects. It slows down execution speed.
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