here is a array in javascripthow to sort by aand outputvar arr=a1a2a3;

To sort the array by the 'a' property, you can use the sort() method along with a comparison function that compares the 'a' property of each object:

arr.sort(function(obj1, obj2){
  return obj1.a - obj2.a;
});

console.log(arr);
// Output: [{'a':1},{'a':2},{'a':3}]

This will sort the array in ascending order based on the 'a' property.

If you want to sort the array in descending order, you can simply reverse the comparison:

arr.sort(function(obj1, obj2){
  return obj2.a - obj1.a;
});

console.log(arr);
// Output: [{'a':3},{'a':2},{'a':1}]