add the sum of all values into array to variable code example

Example 1: sum of all numbers in an array javascript

const arrSum = arr => arr.reduce((a,b) => a + b, 0)

Example 2: javascript sum array values

function getArraySum(a){
    var total=0;
    for(var i in a) { 
        total += a[i];
    }
    return total;
}

var payChecks = [123,155,134, 205, 105]; 
var weeklyPay= getArraySum(payChecks); //sums up to 722

Example 3: Write a function that takes an array of number values and returns the sum.

function amountTotal(amount) {
        var total = 0;
        for (i = 0; i < amount.length; ++i) {
             total += amount[i]; // add each element in an array to total
        }
        return total;// return sum of elements in array
}