如何在javascript中将数组的每个成员乘以标量？-HowdoImultiplyeachmemberofanarraybyascalarinjavascript?

9  

Fast-forward to 2016, when support for ECMAScript 6 is getting better:

快进到2016年，当ECMAScript 6的支持越来越好时：

If you use babeljs or TypeScript in your project to cross-compile your code to ES5 or you don't need to support old browsers and Internet Explorer (Edge has support), you can use ES6 arrow functions:

如果在项目中使用babeljs或TypeScript将代码交叉编译为ES5，或者您不需要支持旧浏览器和Internet Explorer（Edge支持），则可以使用ES6箭头函数：

var a = [1, 2, 3];

var b = a.map(x => x * 5);
//            ^^^^^^^^^^

console.log(b);   // [5, 10, 15]

Arrow functions are a syntactic sugar for an inline function with lexical this binding:

箭头函数是内联函数的语法糖，具有词法结合：

// ES6
array2 = array.map(x => x * 5);

// ES5
array2 = array.map((function (x) { return x * 5; }).bind(this));

4  

Ecmascript 2016 (ES7) defines SIMD mathematics which allow to do multiplications like the one you desire faster and easier. However, as of today there is very little browser support for SIMD (only Firefox nightly builds support this) [1], [2]. This is how it will look like:

Ecmascript 2016（ES7）定义了SIMD数学，它允许像你想要的那样快速和简单地进行乘法运算。但是，到目前为止，浏览器对SIMD的支持很少（只有Firefox夜间构建支持这一点）[1]，[2]。这是它的样子：

var a = SIMD.Float32x4(1, 2, 3);
var b = SIMD.Float32x4(5, 5, 5);
SIMD.Float32x4.mul(a, b);  // Float32x4[5, 10, 15]

Until there will be widespread support for SIMD you'd have to resort to using map

在对SIMD提供广泛支持之前，您不得不求助于使用地图

var a = [1, 2, 3].map(function(x) { return x * 5; });

which is nicely supported by all modern browsers [3].

所有现代浏览器都很好地支持[3]。

2  

You can use .map but you also have to create a new variable to throw the new values in:

您可以使用.map，但您还必须创建一个新变量以将新值抛出：

var a = [1,2,3];

var b = a.map(function(x){
    return x * 5;
});

alert(b);

1  

var a, i, ii, term;

a = [1,2,3];
term = 5;

for (i=0, ii=a.length; i