Math.LN2

Math.LN2

Math.LN2属性表示 2 的自然对数,约为 0.693:

Math.LN2=ln(2)≈0.693\mathtt{\mi{Math.LN2}} = \ln(2) \approx 0.693

| Math.LN2属性的属性特性 |

|:----|

| Writable | no |

| Enumerable | no |

| Configurable | no |

描述

由于LN2Math 的静态属性,所以应该像这样使用:Math.LN2,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.LN2

下面的函数返回 2 的自然对数:

function getNatLog2() { return Math.LN2; } getNatLog2( // 0.6931471805599453

规范

SpecificationStatusComment
ECMAScript 1st Edition (ECMA-262)StandardInitial definition. Implemented in JavaScript 1.0.
ECMAScript 5.1 (ECMA-262)The definition of 'Math.LN2' in that specification.Standard
ECMAScript 2015 (6th Edition, ECMA-262)The definition of 'Math.LN2' in that specification.Standard
ECMAScript Latest Draft (ECMA-262)The definition of 'Math.LN2' in that specification.Draft

浏览器兼容性

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Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)