sum of values from objects code example

Example 1: javascript object total

function sum( obj ) {
  var sum = 0;
  for( var el in obj ) {
    if( obj.hasOwnProperty( el ) ) {
      sum += parseFloat( obj[el] );
    }
  }
  return sum;
}
    
var sample = { a: 1 , b: 2 , c:3 };
var summed = sum( sample );
console.log( "sum: "+summed );

Example 2: javascript sum of number in object array

run.addEventListener("click", function () {
    let sum = people.reduce(function (a, b) { // function(previousValue, currentValue)
      return {
        age: a.age + b.age, //select age in object array
      };
    });
    console.log(sum); //output sum of ages
  });