reversing array elements

reverseArray.js

// in a new array
var reverseArray = function (old_array) {
  var new_array = [];
  for (i=0; i<=old_array.length-1; i++) {
    new_array[old_array.length-1 - i] = old_array[i];  
  }
  return new_array;
}

// in the same array
var reverseArrayInPlace = function (old_array) {
  var left = "";
  var right = "";
  for (i=0; i<=Math.floor((old_array.length-1)/2); i++) {
    left = old_array[i];
    right = old_array[old_array.length - 1 - i];
    old_array[i] = right;
    old_array[old_array.length - 1 - i] = left;
  }
}