Javascript映射数组的每个第n个元素

Question

I just started to learn Javascript by my own and faced quite complex task.

I have array where are 18 labels and another 1d array where are all of the values. The label index place match every nth element in array.

Eg if label index is 0 so then the first element and 19th element belongs to label 1 and 2th and 20th element belongs to label in index 2 .

I wrote this script that create an Object and append the values from correct index, but is there better ways to map values between two arrays?

var labelArrLenght = 18;

var i = 0, sampleArr = [];
while (i < 6642) {
  sampleArr.push(i);
  i++;
};

var i = 0, myObj = {};
while (i < labelArrLenght) {
  myObj[i] = {label:`dummyLabel${i}`, data:[]};
  i++
};

var step1 = sampleArr.length / labelArrLenght;
var stepCounter = 0;

for (var i = 0; i < step1; i++) {
  for (var b = 0; b < labelArrLenght; b++) {
    myObj[b]['data'].push(sampleArr[stepCounter]);
    stepCounter++;
  };
};

Answer 1

You could take a single loop approach and get the index with the remainder operator % .

 var labelArrLenght = 18, sampleArr = [], myObj = {}; for (let i = 0; i < 90; i++) sampleArr.push(i); for (let i = 0; i < labelArrLenght ; i++) myObj[i] = { label: `dummyLabel${i}`, data: [] }; for (var i = 0; i < sampleArr.length; i++) myObj[i % labelArrLenght].data.push(sampleArr[i]); console.log(myObj);

 .as-console-wrapper { max-height: 100% !important; top: 0; }