Property/method

Description

Math.E

Math.LN10

Math.LN2

Math.LOG2E

Math.LOG10E

Math.PI

Math.SQRT1_2

Math.SQRT2

These are some useful math constants, all read-only. Here are their values:

    > Math.E;   
    2.718281828459045   
    > Math.LN10;   
    2.302585092994046   
    > Math.LN2;   
    0.6931471805599453   
    > Math.LOG2E;   
    1.4426950408889634   
    > Math.LOG10E;   
    0.4342944819032518   
    > Math.PI;   
    3.141592653589793   
    > Math.SQRT1_2;   
    0.7071067811865476   
    > Math.SQRT2;   
    1.4142135623730951   

Math.acos(x)

Math.asin(x)

Math.atan(x)

Math.atan2(y, x)

Math.cos(x)

Math.sin(x)

Math.tan(x)

Trigonometric functions

Math.round(x)

Math.floor(x)

Math.ceil(x)

round() gives you the nearest integer, ceil() rounds up, and floor() rounds down:

    > Math.round(5.5);   
    6   
    > Math.floor(5.5);   
    5   
    > Math.ceil(5.1);   
    6   

Math.max(num1, num2, num3, ...)

Math.min(num1, num2, num3, ...)

max() returns the largest and min() returns the smallest of the numbers passed to them as arguments. If at least one of the input parameters is NaN, the result is also NaN:

    > Math.max(4.5, 101, Math.PI);   
    101   
    > Math.min(4.5, 101, Math.PI);   
    3.141592653589793   

Math.abs(x)

Absolute value:

    > Math.abs(-101);   
    101   
    > Math.abs(101);   
    101   

Math.exp(x)

Exponential function: Math.E to the power of x:

    > Math.exp(1) === Math.E;   
    true   

Math.log(x)

Natural logarithm of x:

    > Math.log(10) === Math.LN10;   
    true

Math.sqrt(x)

Square root of x:

    > Math.sqrt(9);   
    3   
    > Math.sqrt(2) === Math.SQRT2;   
    true   

Math.pow(x, y)

x to the power of y:

    > Math.pow(3, 2);   
    9   

Math.random()

Random number between 0 and 1 (including 0).

    > Math.random();   
    0.8279076443185321   
    For an random integer in a range,
     say between 10 and 100:   
    > Math.round(Math.random() * 90   + 10);   
    79