javascript - Get size of dimensions in array

Question

How to get the dimensions given a multidimensional array?
Edit: it could be of 1, 2, or 3 dimensions but each sub-array has the same length.

i.e. for

var a = [[1,1,1], [1,1,1]]

would be [2,3]

Answer 1

const dimensions = [ arr.length, arr[0].length ];

This works, if you know length of the inner arrays never change.

---

If the dimension of the inner arrays aren't static (jagged array), you could combine Array.reduce and Math.max to calculate the largest dimension:

const dimensions = [
    arr.length,
    arr.reduce((x, y) => Math.max(x, y.length), 0)
];