Chartjs-How to access array inside object without keys

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1👍

✅

You can do it as two calls to map():

const labels = myArr.chart.map(el => el[0]);
const data = myArr.chart.map(el => el[1]);

1👍

This seems to me like an invented problem.

If your data points are just x and y values, there’s nothing wrong with saying the first array element is x and the second is y.

There are some people who would argue and say you should make it an Object with properties like xValue and yValue.

However, any upsides or downsides in either case would be marginal. You could imagine someone saying the Object version is more readable. The Object version is harder to optimize by the javascript runtime (V8 at least): https://v8.dev/blog/elements-kinds

Unless you have measured it, and it matters, it doesn’t matter.

1👍

You can use .reduce() in as follows:

const myArr = {
  "chart":[
     [
        1627776011000,
        28
     ],
     [
        1627776371000,
        38
     ],
     [
        1627776731000,
        48
     ]
    ]
};

const [labels, data] = myArr.chart.reduce((acc,cur) => [
    [...acc[0], cur[0]],
    [...acc[1],cur[1]]],
[[],[]]);
console.log( labels, data );

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