How to convert simple array into two-dimensional array (matrix) with Javascript

Question

Imagine I have an array:

A = Array(1, 2, 3, 4, 5, 6, 7, 8, 9);

And I want it to convert into 2-dimensional array (matrix of N x M), for ins

Answer 1

function matrixify(array, n, m) {
    var result = [];
    for (var i = 0; i < n; i++) {
        result[i] = array.splice(0, m);
    }
    return result;
}
a = matrixify(a, 3, 3);