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Math.LOG2E

Math.LOG2E

Math.LOG2E属性表示以 2 为底数,e 的对数,约为 1.442:

Math.LOG2E=log2(e)≈1.442\mathtt{\mi{Math.LOG2E}} = \log_2(e) \approx 1.442

| Math.LOG2E属性的属性特性 |

|:----|

| Writable | no |

| Enumerable | no |

| Configurable | no |

描述

由于LOG2EMath 的静态属性,所以应该像这样使用:Math.LOG2E,而不是作为你创建的 Math对象的属性(Math不是一个构造函数)。

示例

使用Math.LOG2E

下面的函数返回以 2 为底数,E 的对数:

function getLog2e() { return Math.LOG2E; } getLog2e( // 1.4426950408889634

规范

SpecificationStatusComment
ECMAScript 1st Edition (ECMA-262)StandardInitial definition. Implemented in JavaScript 1.0.
ECMAScript 5.1 (ECMA-262)The definition of 'Math.LOG2E' in that specification.Standard
ECMAScript 2015 (6th Edition, ECMA-262)The definition of 'Math.LOG2E' in that specification.Standard
ECMAScript Latest Draft (ECMA-262)The definition of 'Math.LOG2E' in that specification.Draft

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