Calculate average

Подсчет среднего для значений объектов в массиве

by Vallek

JavaScript

let array = [
    {name: "Bob", age: 25},
    {name: "Alice", age: 17},
    {name: "David", age: 30}
]

// Стрелочные функции
let items = array.map(cur => cur.age);
let average = arr => arr.reduce( ( acc, cur ) => acc + cur, 0 ) / arr.length;
let result = average(items);
console.log(result);

// Без стрелочных
items2 = array.map(
	function(cur) {
		return cur.age;
	}
)
average = function(arr){
	return arr.reduce(function(acc, cur){
		return acc + cur
	}, 0) / arr.length;
}
let result2 = average(items2);
console.log(result2);

// Для старых браузеров
let items3 = [];
for (i = 0; i < array.length; i++) {
	age = array[i].age;
	items3.push(age);
}
	
let sum = 0;
for (var i = 0; i < items3.length; i++ ){
    sum += parseInt( items3[i], 10 );
}
let result3 = sum/items3.length;
console.log(result3);