How to sum elements at the same index in array of arrays into a single array?

Question

Let\'s say that I have an array of arrays, like so:

[
  [0, 1, 3],
  [2, 4, 6],
  [5, 5, 7],
  [10, 0, 3]
]

How do I generate a new array t

Answer 1

One-liner in ES6, with map and reduce

var a = [ [0, 1, 3], [2, 4, 6], [5, 5, 7], [10, 0, 3] ];

var sum = a[0].map((_, i) => a.reduce((p, _, j) => p + a[j][i], 0));

document.write(sum);