JavaScript: Calculate the sum of values in an array

JavaScript Math: Exercise-17 with Solution

Write a JavaScript function to calculate the sum of values in an array.

Test Data :
console.log(sum([1,2,3]));
console.log(sum([100,-200,3]));
console.log(sum([1,2,'a',3]));
Output :
6
-97
6

Visual Presentation:

Sample Solution:

JavaScript Code:

// Define a function named sum that calculates the sum of an array of numbers.
function sum(input){
    // Check if the input is an array, if not, return false.
    if (toString.call(input) !== "[object Array]")
        return false;
      
    var total = 0;
    // Iterate through the input array and sum the numeric elements.
    for(var i = 0; i < input.length; i++) {
        // If the element is not a number, skip to the next element.
        if(isNaN(input[i])){
            continue;
        }
        // Add the numeric value of the element to the total.
        total += Number(input[i]);
    }
    // Return the total sum.
    return total;
}

// Output the sum of the numbers in the array [1, 2, 3] to the console.
console.log(sum([1, 2, 3]));
// Output the sum of the numbers in the array [100, -200, 3] to the console.
console.log(sum([100, -200, 3]));
// Output the sum of the numbers in the array [1, 2, 'a', 3] to the console.
console.log(sum([1, 2, 'a', 3]));

Output:

6
-97
6

Flowchart:

Live Demo:

See the Pen javascript-math-exercise-17 by w3resource (@w3resource) on CodePen.

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