JavaScript: The Definitive Guide, 6th Edition

Name

Math — mathematical functions and constants

Synopsis

Math.constant
Math.function()

Constants

Math.E

The constant e, the base of the natural logarithm.

Math.LN10

The natural logarithm of 10.

Math.LN2

The natural logarithm of 2.

Math.LOG10E

The base-10 logarithm of e.

Math.LOG2E

The base-2 logarithm of e.

Math.PI

The constant π.

Math.SQRT1_2

The number 1 divided by the square root of 2.

Math.SQRT2

The square root of 2.

Static Functions

Math.abs()

Computes an absolute value.

Math.acos()

Computes an arccosine.

Math.asin()

Computes an arcsine.

Math.atan()

Computes an arctangent.

Math.atan2()

Computes the angle from the X axis to a point.

Math.ceil()

Rounds a number up.

Math.cos()

Computes a cosine.

Math.exp()

Computes a power of e.

Math.floor()

Rounds a number down.

Math.log()

Computes a natural logarithm.

Math.max()

Returns the larger of two numbers.

Math.min()

Returns the smaller of two numbers.

Math.pow()

Computes x ^y

Math.random()

Computes a random number.

Math.round()

Rounds to the nearest integer.

Math.sin()

Computes a sine.

Math.sqrt()

Computes a square root.

Math.tan()

Computes a tangent.

Description

Math is an object that defines properties that refer to useful mathematical functions and constants. These functions and constants are invoked with syntax like this:

y = Math.sin(x);
area = radius * radius * Math.PI;

Math is not a class of objects as Date and String are. There is no Math() constructor, and functions like Math.sin() are simply functions, not methods that operate on an object.

See Also

Number