how to sum property values of arrays created by reduce

Question

This is my code :

var array = 
  [
    {
      id: "BG",
      qty: 100
    }, 
    {
      id: "BG",
      qty: 35
    }, 
    {
      id: "JP",
      qty: 75
    },
    {
      id: "JP",
      qty: 50
    }
 ];


var result = array.reduce((obj, cur) => (obj[cur.id] = [...(obj[cur.id] || []), cur], obj), {})
console.log(result);

What I would like to do is group the array into sub arrays based on the ID's which the array.reduce does. But now I want to sum the total of the qty.

So I'm expecting values the total qty for BG to be = 35 and the total qty for JP to be 125, and then I want to be able to run math conditions on those numbers

Could you not have used the information you received from the question you asked an hour ago to decipher the solution? — code
– code, Commented Nov 15, 2022 at 23:00

IT goldman · Accepted Answer · 2022-11-15 23:01:16Z

1

It really have been asked before, but by the time I'd search for it I could also write it. It's not that long.

var array = [{
    id: "BG",
    qty: 100
  },
  {
    id: "BG",
    qty: 35
  },
  {
    id: "JP",
    qty: 75
  },
  {
    id: "JP",
    qty: 50
  }
];

var result = Object.values(array.reduce(function(agg, item) {
  agg[item.id] = agg[item.id] || {
    id: item.id,
    qty: 0
  }
  agg[item.id].qty += item.qty;
  return agg;
}, {}));

console.log(result);

answered Nov 15, 2022 at 23:01

IT goldman

20.4k2 gold badges18 silver badges34 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

how to sum property values of arrays created by reduce

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related