Using for..in to iterate object and reduce to iterate array

var data = [{costOfAirtickets: 2500, costOfHotel: 1200},{costOfAirtickets: 1500, costOfHotel: 1000}];

var result = [data.reduce((acc, n) => {
  for (var prop in n) {
    if (acc.hasOwnProperty(prop)) acc[prop] += n[prop];
    else acc[prop] = n[prop];
  }
  return acc;
}, {})]
console.log(result)

Try:

sum += parseInt($scope.logs[i].intTime);

Instead of:

sum += $scope.logs[i].intTime;

EDIT: I would recommend you have a look at reduce function, which is the javascript way of looping on your array in this case: https://www.w3schools.com/jsref/jsref_reduce.asp

EDIT2: You initialize $scope.logs.intTime to "". This first value stays in your array and generates NaN. I suggest you initialize your array like this:

$scope.logs = [];

Your question is more general javascriptthan angular

You can sum element of array by using the Array.reduce function

You can sum on a specific status by filtering first

Ie

const sum = this.data.filter(item => item.status === 'settled')
                     .reduce((acc, item) => acc + Number(item.claimed_value), 0);

Note that as said in comment you received a string and not a numberso you must convert it at first (see the Number() function in thereduceclosure)) otherwise the+` operator will just concatenate the string

Use Array#Reduce:

// Array of numbers
var array = [1,2,3,4,5];
var sum = array.reduce((acc, cur) => acc + cur, 0);
console.log(sum)

// Array of strings
var toNumber = ['1','2','3','4','5'];
var sumNumber = toNumber.reduce((acc, cur) => acc + Number(cur), 0)
console.log(sumNumber);

In component declare :-

public total;

this.total= this.adherant.reduce((prev,next)=>prev+next.mont,0);

Use it like {{total}} in template

In your current implementation you basically iterate over all items within the items array and return the objects mediaShare property.

this.totalCount = this.items.map((item)=> item.mediaShare); // => ["123", "345", ...]

What you actually want to do is to get the sum of all these values. Considering the values inside totalCount are now a collection of strings that seem to hold a numeric value, you can do the following:

this.totalCount = this.items.map((item)=> Number.parseInt(item.mediaShare)).reduce((acc, curr) => acc + curr, 0); // Or `parseFloat`, if your values might be of type float

Read up on Array.prototype.reduce to learn how it behaves.

Arrays in JavaScript/TypeScript also have these kind of methods. You can again filter with you condition and then use reduce aggregation function to sum the items.

Copyconst sum = receiptItems.filter(item => item.tax === '25.00')
                        .reduce((sum, current) => sum + current.total, 0);

item.tax === '25.00' - this part you must adjust with your logic

Here you go:

const data={
    2:{3:"3514.80", 4:"7259.32"},
    5:{6:"864941.86", 7:"1076976.54"},
    8:{"":"14145.69"},
    9:{10:"223835.02", 11:"60978.31", 12:"5554.92"}
}

const result = Object.values(data).map(items => Object.values(items).map(val => Number(val)).reduce((a,b) => a + b, 0))

console.log(result)

The correct way of using JavaScript's reduce function (which is also valid for TypeScript) would be:

const response = {
  "carts": {
    "value": [
      {
        "Amt": 40
      },
      {
        "Amt": 20.25
      },
      {
        "Amt": 10.30
      }
    ]
  }
};

const total = response.carts.value.reduce((sum, item) => sum + item.Amt, 0);

console.log(total);

Note that if you want to support IE8 you have to include a polyfill (like that on MDN's page).