Nuestros voluntarios aún no han traducido este artículo al Español. Únete a nosotros y ayúdanos a traducirlo
The Math.sign()
function returns the sign of a number, indicating whether the number is positive, negative or zero.
Syntax
Math.sign(x)
Parameters
x
- A number.
Return value
A number representing the sign of the given argument. If the argument is a positive number, negative number, positive zero or negative zero, the function will return 1
, -1
, 0
or -0
respectively. Otherwise, NaN
is returned.
Description
Because sign()
is a static method of Math
, you always use it as Math.sign()
, rather than as a method of a Math
object you created (Math
is not a constructor).
This function has 5 kinds of return values, 1
, -1
, 0
, -0
, NaN
, which represent "positive number", "negative number", "positive zero", "negative zero" and NaN
respectively.
The argument passed to this function will be converted to x
type implicitly.
Examples
Using Math.sign()
Math.sign(3); // 1 Math.sign(-3); // -1 Math.sign('-3'); // -1 Math.sign(0); // 0 Math.sign(-0); // -0 Math.sign(NaN); // NaN Math.sign('foo'); // NaN Math.sign(); // NaN
Polyfill
Math.sign = Math.sign || function(x) { x = +x; // convert to a number if (x === 0 || isNaN(x)) { return Number(x); } return x > 0 ? 1 : -1; }
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Math.sign' in that specification. |
Standard | Initial definition. |
ECMAScript 2017 Draft (ECMA-262) The definition of 'Math.sign' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | 38 | 25 (25) | No support | 25 | No support |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | No support | No support | 25.0 (25) | No support | No support | No support |