Javascript – Get size of dimensions in array

javascriptmultidimensional-array

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]

Best Answer

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)
];