JavaScript sum of array and object; Through this tutorial, i am going to show you how calculate sum of array values and sum array of objects by key using for loop, map, and reduce() method
JavaScript Sum Array and Array Of Object
Use the following ways and method to calculate sum array of objects by key in javaScript; As shown below:
- Sum of Array in JavaScript
- Sum of Array javaScript Reduce
- JavaScript Sum Array Values using Map() method
- JavaScript Sum of Array of Objects
- JavaScript Sum of Array of Objects Reduce
Sum of Array in JavaScript
Let’s see the following example for sum of array in javascript using for loop; as shown below:
var numArr = [10, 20, 30, 40] // sums to value = 100 var sum = 0; for (var i = 0; i < numArr.length; i++) { sum += numArr[i] } document.write( "javascript- Sum of the array value is :- " + sum );
Result of the above code is :- 100
Sum of Array javaScript Reduce
To calculate sum of array using reduce() method in javaScript; as shown below:
var numArr = [10, 20, 30, 40] // sums to value = 100 var sum = numArr.reduce(function(a, b){return a+b;}) document.write( "javascript- Sum of the array value is :- " + sum );
Result of the above code is: 150
JavaScript Sum Array Values using Map() method
To find sum of array values using map() method in javaScript; as shown below:
var numArr = [10, 20, 30, 40] // sums to value = 100 var sum = 0; numArr.map(function(x){sum+=x}) document.write( "javascript- Sum of the array value is :- " + sum );
Result of the above code is:- 105
JavaScript Sum of Array of Objects
To find sum array of objects by key using for loop in JavaScript; as shown below:
var numArr = [ { name: 'a', num: 50}, { name: 'b', num: 50}, { name: 'c', num: 75}, { name: 'd', num: 35}, { name: 'e', num: 25 }, ]; var sum = 0; for (var i = 0; i < numArr.length; i++) { sum += numArr[i].num } document.write( "javascript- Sum of the array value is :- " + sum );
JavaScript Sum of Array of Objects Reduce
Using javaScript reduce() method, you can find sum array of objects by key; as shown below:
var numArr = [ { name: 'a', num: 50}, { name: 'b', num: 50}, { name: 'c', num: 75}, { name: 'd', num: 35}, { name: 'e', num: 25 }, { name: 'f', num: 40 }, ]; var sum = numArr.reduce(function (total, currentValue) { return total + currentValue.num; }, 0); document.write( "javascript- Sum of the array value is :- " + sum );
Result of the above code is:- 275