How to create multiple array from single array?-CodePudding

I have a situation where I get the data in an array and I have to convert that to multiple arrays... Like Matrix.

const array = [1,2,3,4,5,6,7,8,9]

the output should be:

[[1,3],[2,4],[5,7],[6,8],[9]]

this is what I have so far:

let i = 0;
const add = [];
while (i < list.length) {
  add.push([list[i], list[i   2]]);
  i = i   1;
}
return add;

CodePudding user response：

Maybe try this one?

let i = 0;
const list = [1,2,3,4,5,6,7,8,9]
const add = [];
let newarr =[]
while (i < list.length) {
  add.push([list[i], list[i   2]]);
  add.push([list[i 1],list[i 3]])
  i  =4;
}
//remove undefined item from the array
newarr = add.map(arr=>arr.filter(item =>item != undefined)).filter(item=>item!="")


console.log(newarr)

CodePudding user response：

const array = [1,2,3,4,5,6,7,8,9];
const visitedIndex = [];
const newArray = [];
array.forEach((element, i) => {
  if (!visitedIndex.includes(i)) {
    if (array[i 2]) {
      newArray.push([array[i], array[i 2]])
    } else {
      newArray.push([array[i]])
    }
    visitedIndex.push(i);
    visitedIndex.push(i 2);
  };

});

CodePudding user response：

Lodash chunk if you don't mind.

Or you can use recursive approach in vanila js.

const array = [1,2,3,4,5,6,7,8,9];

const chunk = (arr, n) => arr.length ? [arr.slice(0, n), ...chunk(arr.slice(n), n)] : [];

console.log(chunk(array, 2));

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