How can I split an array into chunks but have it f

问题:

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

function chunkArray(myArray, chunk_size) {
    let results = [];
    while (myArray.length) {
        results.push(myArray.splice(0, chunk_size));
    }
    return results;
}

However, if we assume that the original array is [1, 2, 3, 4, 5, 6] and I'm chunking it into 3 parts, I'll end up with this:

[
    [1, 2],
    [3, 4],
    [5, 6]
]

But, I'd instead like it to chunk into the arrays jumping between the three, ex:

[
    [1, 4],
    [2, 5],
    [3, 6]
]

What would be the best way to do this?

回答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)

回答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);

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回答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;
}