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Math.SQRT2

Math.SQRT2

Math.SQRT2属性表示 2 的平方根,约为 1.414:

Math.SQRT2 =2≈1.414\ mathtt {\ mi {Math.SQRT2}} = \ sqrt {2} \ approx 1.414

| Math.SQRT2的属性特性 |

|:----|

| Writable | no |

| Enumerable | no |

| Configurable | no |

描述

由于 SQRT2 是 Math 的静态属性,所以应该像这样使用:Math.SQRT2,而不是作为你创建的Math实例的属性(Math不是构造函数)。

示例

使用Math.SQRT2

下面的函数返回 2 的平方根:

function getRoot2() { return Math.SQRT2; } getRoot2( // 1.4142135623730951

规范

SpecificationStatusComment
ECMAScript 1st Edition (ECMA-262)StandardInitial definition. Implemented in JavaScript 1.0.
ECMAScript 5.1 (ECMA-262)The definition of 'Math.SQRT2' in that specification.Standard
ECMAScript 2015 (6th Edition, ECMA-262)The definition of 'Math.SQRT2' in that specification.Standard
ECMAScript Latest Draft (ECMA-262)The definition of 'Math.SQRT2' in that specification.Draft

浏览器兼容性

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