Filter subarrays in an array

Question

I must be losing my mind. Suppose I have an array of arrays. I want to filter the subarrays and end up with an array of filtered subarrays. Say my filter is "greater than 3". So

let nested = [[1,2],[3,4],[5,6]]
 // [[],[4][5,6]]

After some underscore jiggery-pokery failed, I tried regular for loops.

for (var i = 0; i < nested.length; i++){
  for (var j = 0; j < nested[i].length; j++){
    if (nested[i][j] <= 3){
      (nested[i]).splice(j, 1)
    }
  }
}

But this only removes the 1 from the first subarray. I would have thought that splice mutates the underlying array, and the length will be updated to account for that, but maybe not? Or maybe something else entirely is going wrong. Probably obvious; not seeing it. Any fancy or simple help gratefully accepted.

Answer 1

This might do it;

var nested = [[1,2],[3,4],[5,6]],
     limit = 3,
    result = nested.map(a => a.filter(e => e > limit ));
console.log(result);

Answer 2

If you don't have ES6 :

var nested = [[1,2],[3,4],[5,6]];

nested.map(
  function(x) {
    return x.filter(
      function(y){
        return y > 3
      }
    )
  }
)