Math.log10() function returns the base 10 logarithm of a number, that is

x > 0 , Math.log10 ( x ) = log 10 ( x ) = the unique y such that 10 y = x \forall x > 0, \mathtt{\operatorname{Math.log10}(x)} = \log_10(x) = \text{the unique} \; y \; \text{such that} \; 10^y = x

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

句法

Math.log10(x)
					

参数

x

A number.

返回值

The base 10 logarithm of the given number. If the number is negative, NaN 被返回。

描述

If the value of x is less than 0, the return value is always NaN .

因为 log10() is a static method of Math , you always use it as Math.log10() , rather than as a method of a Math object you created ( Math is not a constructor).

This function is the equivalent of Math.log(x) / Math.log(10).  For log10(e) use the constant Math.LOG10E which is 1 / Math.LN10 .

范例

使用 Math.log10()

Math.log10(2);      // 0.3010299956639812
Math.log10(1);      // 0
Math.log10(0);      // -Infinity
Math.log10(-2);     // NaN
Math.log10(100000); // 5
					

Polyfill

This can be emulated with the following function:

Math.log10 = Math.log10 || function(x) {
  return Math.log(x) * Math.LOG10E;
};
					

规范

规范
ECMAScript (ECMA-262)
The definition of 'Math.log10' in that specification.

浏览器兼容性

更新 GitHub 上的兼容性数据
Desktop Mobile Server
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet Node.js
log10 Chrome 38 Edge 12 Firefox 25 IE No Opera 25 Safari 8 WebView Android 38 Chrome Android 38 Firefox Android 25 Opera Android 25 Safari iOS 8 Samsung Internet Android 3.0 nodejs 0.12

图例

完整支持

完整支持

不支持

不支持

另请参阅

元数据

  • 最后修改: