Math.cbrt()

This is an experimental technology, part of the Harmony (ECMAScript 6) proposal.
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future version of browsers as the spec changes.

Summary

The Math.cbrt() function returns the cube root of a number, that is

Math.cbrt(x)=x3=the uniqueysuch thaty3=x\mathtt{Math.cbrt(x)} = \sqrt[3]{x} = \text{the unique} \; y \; \text{such that} \; y^3 = x

Syntax

Math.cbrt(x)

Parameters

x
A number.

Description

Because cbrt is a static method of Math, you always use it as Math.cbrt(), rather than as a method of a Math object you created (Math is not a constructor).

Examples

Example: Using Math.cbrt()

Math.cbrt(-1); // -1
Math.cbrt(0);  // 0
Math.cbrt(1);  // 1

Math.cbrt(2);  // 1.2599210498948734

Polyfill

For all x0x \geq 0, have x3=x1/3\sqrt[3]{x} = x^{1/3} so this can be emulated by the following function:

function cbrt(x) {
    var y = Math.pow(Math.abs(x), 1/3);
    return x < 0 ? -y : y;
}

Specifications

Specification Status Comment
ECMAScript Language Specification 6th Edition (ECMA-262) Draft Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support Not supported 25 (25) Not supported Not supported Not supported
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support Not supported Not supported 25.0 (25) Not supported Not supported Not supported

 

Document Tags and Contributors

Contributors to this page: fred.wang, fscholz
Last updated by: fred.wang,