How can I split an array into chunks but have it fill each array by going one by one

Question

I\'m using this function to create chunks of an array:

function chunkArray(myArray, chunk_size) {
    let results = [];
    while (myArray.length) {
                


        

Answer 1

You can use the following code:

function chunkArray(myArray, chunk_size) {
    let results = new Array(chunk_size);
    for(let i = 0; i < chunk_size; i++) {
        results[i] = []
    }
    // append arrays rounding-robin into results arrays.
    myArray.forEach( (element, index) => { results[index % chunk_size].push(element) });
    return results;
}

const array = [1,2,3,4,5,6];
const result = chunkArray(array, 3)
console.log(result)

Answer 2

You could use the remainder of the index with the wanted size for the index and push the value.

var array = [1, 2, 3, 4, 5, 6],
    size = 3,
    result = array.reduce((r, v, i) => {
        var j = i % size;
        r[j] = r[j] || [];
        r[j].push(v);
        return r;
    }, []);

console.log(result);

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

Answer 3

I'd do something like this:

function chunkArray(src, chunkSize ) {
  const chunks = Math.ceil( src.length / chunkSize );
  const chunked = [];

  for (let i = 0; i < src.length; ++i) {
    const c       = i % chunks;
    const x       = chunked[c] || (chunked[c]=[]);
    x[ x.length ] = src[i];
  }

  return chunked;
}