Math.log2() - JavaScript 编辑

概述

Math.log2() 函数返回一个数字以 2 为底的对数.

语法

Math.log2(x)

参数

x

任意数字.

描述

如果传入的参数小于 0, 则返回 NaN.

示例

Math.log2(2)     // 1
Math.log2(1024)  // 10
Math.log2(1)     // 0
Math.log2(0)     // -Infinity
Math.log2(-2)    // NaN
Math.log2("1024")// 10
Math.log2("foo") // NaN

规范

Specification	Status	Comment
ECMAScript 2015 (6th Edition, ECMA-262) Math.log2	Standard	Initial definition.

浏览器兼容性

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

• Desktop
• Mobile

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari
Basic support	未实现	25 (25)	未实现	未实现	未实现

Feature	Android	Chrome for Android	Firefox Mobile (Gecko)	IE Mobile	Opera Mobile	Safari Mobile
Basic support	未实现	未实现	25.0 (25)	未实现	未实现	未实现

相关链接

• Math 对象.