创建多维数组Javascript中的矩阵 [英] Creating multidimensional arrays & matrices in Javascript

问题描述

尝试创建给定数字的函数mCreate()会返回多维数组(矩阵):

Trying to create a function mCreate() that given a set a numbers returns a multidimensional array (matrix):

mCreate(2, 2, 2)    
//   [[[0, 0], [0, 0]], [[0, 0], [0, 0]]]

当此函数仅处理2个深度级别时，即:mCreate(2, 2) //[[0, 0], [0, 0]]我知道要进行2个级别，您可以使用2个嵌套的for loops，但是我遇到的问题是如何处理第n个参数

When this functions handles just 2 levels of depth ie: mCreate(2, 2) //[[0, 0], [0, 0]] I know to do 2 levels, you can use 2 nested for loops but the problem I'm having is how to handle an n'th number of arguments.

使用递归是否可以更好地解决此问题，否则在给定参数数量的情况下，如何动态确定需要使用的嵌套for loops数量?

Would this problem be better approached with recursion, otherwise how can I dynamically determine the number of nested for loops I'm going to need given the number of arguments?

ps:最有效的方法很棒，但不是必不可少的

ps: the most performant way would be great but not essential

重新编辑-使用Benchmark.js检查性能之后，结果如下:

RE-EDIT - After using Benchmark.js to check perf the results were as follows:

BenLesh x 82,043 ops/sec ±2.56% (83 runs sampled)
Phil-P x 205,852 ops/sec ±2.01% (81 runs sampled)
Brian x 252,508 ops/sec ±1.17% (89 runs sampled)
Rick-H x 287,988 ops/sec ±1.25% (82 runs sampled)
Rodney-R x 97,930 ops/sec ±1.67% (81 runs sampled)
Fastest is Rick-H

@briancavalier也提出了一个很好的解决方案 JSbin :

@briancavalier also came up with a good solution JSbin:

const mCreate = (...sizes) => (initialValue) => _mCreate(sizes, initialValue, sizes.length-1, 0)

const _mCreate = (sizes, initialValue, len, index) =>
    Array.from({ length: sizes[index] }, () => 
        index === len ? initialValue : _mCreate(sizes, initialValue, len, index+1))
mCreate(2, 2, 2)(0)

推荐答案

一个简单的递归答案是这样的(在ES2015中):

One simple recursive answer is this (in ES2015):

const mCreate = (...sizes) => 
    Array.from({ length: sizes[0] }, () => 
        sizes.length === 1 ? 0 : mCreate(...sizes.slice(1)));

此处有JS Bin

我想我会用一个高阶函数添加初始化器:

I think I'd add the initializer in with a higher order function though:

const mCreate = (...sizes) => (initialValue) => 
    Array.from({ length: sizes[0] }, () => 
        sizes.length === 1 ? initialValue : mCreate(...sizes.slice(1))(initialValue));

可以像这样使用:

mCreate(2, 2, 2)('hi'); 
// [[["hi", "hi"], ["hi", "hi"]], [["hi", "hi"], ["hi", "hi"]]]

相应的JSBin

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