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The Number.POSITIVE_INFINITY
property represents the positive Infinity value.
You do not have to create a Number
object to access this static property (use Number.POSITIVE_INFINITY
).
Property attributes of Number.POSITIVE_INFINITY |
|
---|---|
Writable | no |
Enumerable | no |
Configurable | no |
Description
The value of Number.POSITIVE_INFINITY
is the same as the value of the global object's Infinity
property.
This value behaves slightly differently than mathematical infinity:
- Any positive value, including
POSITIVE_INFINITY
, multiplied byPOSITIVE_INFINITY
isPOSITIVE_INFINITY
. - Any negative value, including
NEGATIVE_INFINITY
, multiplied byPOSITIVE_INFINITY
isNEGATIVE_INFINITY
. - Zero multiplied by
POSITIVE_INFINITY
isNaN
. NaN
multiplied byPOSITIVE_INFINITY
isNaN
.POSITIVE_INFINITY
, divided by any negative value exceptNEGATIVE_INFINITY
, isNEGATIVE_INFINITY
.POSITIVE_INFINITY
, divided by any positive value exceptPOSITIVE_INFINITY
, isPOSITIVE_INFINITY
.POSITIVE_INFINITY
, divided by eitherNEGATIVE_INFINITY
orPOSITIVE_INFINITY
, isNaN
.- Any number divided by
POSITIVE_INFINITY
is Zero.
You might use the Number.POSITIVE_INFINITY
property to indicate an error condition that returns a finite number in case of success. Note, however, that isFinite
would be more appropriate in such a case.
Examples
Using POSITIVE_INFINITY
In the following example, the variable bigNumber
is assigned a value that is larger than the maximum value. When the if
statement executes, bigNumber
has the value Infinity
, so bigNumber
is set to a more manageable value before continuing.
var bigNumber = Number.MAX_VALUE * 2; if (bigNumber == Number.POSITIVE_INFINITY) { bigNumber = returnFinite(); }
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 1st Edition (ECMA-262) | Standard | Initial definition. Implemented in JavaScript 1.1. |
ECMAScript 5.1 (ECMA-262) The definition of 'Number.POSITIVE_INFINITY' in that specification. |
Standard | |
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Number.POSITIVE_INFINITY' in that specification. |
Standard | |
ECMAScript 2017 Draft (ECMA-262) The definition of 'Number.POSITIVE_INFINITY' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |