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The Math.PI
property represents the ratio of the circumference of a circle to its diameter, approximately 3.14159:
Property attributes of Math.PI |
|
---|---|
Writable | no |
Enumerable | no |
Configurable | no |
Description
Because PI
is a static property of Math
, you always use it as Math.PI
, rather than as a property of a Math
object you created (Math
is not a constructor).
Examples
Using Math.PI
The following function uses Math.PI
to calculate the circumference of a circle with a passed radius.
function calculateCircumference(radius) { return 2 * Math.PI * radius; } calculateCircumference(1); // 6.283185307179586
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 1st Edition (ECMA-262) | Standard | Initial definition. Implemented in JavaScript 1.0. |
ECMAScript 5.1 (ECMA-262) The definition of 'Math.PI' in that specification. |
Standard | |
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Math.PI' in that specification. |
Standard | |
ECMAScript 2017 Draft (ECMA-262) The definition of 'Math.PI' 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) |