使用 lodash 将数组映射到对象答案

【问题标题】：Mapping an array to a object with lodash使用 lodash 将数组映射到对象
【发布时间】：2018-11-08 15:40:05
【问题描述】：

我有这个数组：

[ [ '2018-05-28T21:51:00Z',
    0.00000858,
    0.00000857,
    0.00000860,
    0.00000855,
    12511.81490226 ],
  [ '2018-05-28T21:52:00Z',
    0.00000853,
    0.00000850,
    0.00000856,
    0.00000847,
    12687.20140187 ],
  [ '2018-05-28T21:53:00Z',
    0.00000848,
    0.00000847,
    0.00000850,
    0.00000846,
    12708.9320888 ]
]

我需要把它改成这样：

{ 
    T: [ '2018-05-28T21:51:00Z', '2018-05-28T21:52:00Z', '2018-05-28T21:53:00Z' ],
    O: [ 0.00000858, 0.00000853, 0.00000848],
    C: [ 0.00000857, 0.00000850, 0.00000847],
    H: [ 0.00000860, 0.00000856, 0.00000850],
    L: [ 0.00000855, 0.00000847, 0.00000846],
    V: [ 12511.81490226, 12687.20140187, 12708.9320888 ]
}

这是预定义的位置，第一个值总是'T'，第二个值总是'O'等等。

像这样尝试使用 lodash

_.zipObject(['T', 'O', 'H', 'L', 'C'], s.values)

但结果并非预期。有什么建议吗？

【问题讨论】：

标签： javascript arrays node.js lodash

【解决方案1】：

不需要库，您可以使用纯 Javascript 轻松完成此操作：

const input=[['2018-05-28T21:51:00Z',0.00000858,0.00000857,0.00000860,0.00000855,12511.81490226],['2018-05-28T21:52:00Z',0.00000853,0.00000850,0.00000856,0.00000847,12687.20140187],['2018-05-28T21:53:00Z',0.00000848,0.00000847,0.00000850,0.00000846,12708.9320888]]
const keys = ['T', 'O', 'C', 'H', 'L', 'V'];
const arrs = input.reduce((accum, item) => {
  keys.forEach((key, i) => accum[key].push(item[i]));
  return accum;
}, keys.reduce((a, key) => { a[key] = []; return a }, {}));
console.log(arrs);

【讨论】：

【解决方案2】：

您可以这样做：

const trans  = data[0].map((col, i) => data.map(row => row[i]));

_.zipObject(['T', 'O', 'H', 'L', 'C'], trans)

data 是您的初始数组。

【讨论】：

【解决方案3】：

您只需使用 zip 和 zipobject 即可：

var input = [ [ '2018-05-28T21:51:00Z',
    0.00000858,
    0.00000857,
    0.00000860,
    0.00000855,
    12511.81490226 ],
  [ '2018-05-28T21:52:00Z',
    0.00000853,
    0.00000850,
    0.00000856,
    0.00000847,
    12687.20140187 ],
  [ '2018-05-28T21:53:00Z',
    0.00000848,
    0.00000847,
    0.00000850,
    0.00000846,
    12708.9320888 ]
];

var output = _.zipObject(['T', 'O', 'H', 'L', 'C'], _.zip.apply(_, input));

&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/1.2.1/lodash.min.js"&gt;&lt;/script&gt;

【讨论】：