Using JavaScript to Multiply All Elements in an Array

In JavaScript, we can multiply all elements in an array easily by making use of a for loop. We simply loop through all elements in the array and multiply them together.

Here is some simple code to do this:

var array_of_numbers = [9,3,2,4];
var total = array_of_numbers[0];
for( var i=1; i<array_of_numbers.length; i++ ){
  total = total * array_of_numbers[i];
};

Let’s put our code above in a function so we can make it really easy to multiply all elements of an array.

function multiplyArray(arr){
  var total = arr[0];
  for( var i=1; i<arr.length; i++ ){
    total = total * arr[i];
  }
  return total;
};

In the above function multiplyArray, as you can see it takes only one parameter, arr, which is the array you want to multiply all elements of.

Finally, let’s see our function in action with an example:

function multiplyArray(arr){
  var total = arr[0];
  for( var i=1; i<arr.length; i++ ){
    total = total * arr[i];
  }
  return total;
};

var array_of_numbers = [9,3,2,4];

console.log(multiplyArray(array_of_numbers));

#Output:
216

When working with arrays of numbers, the ability to summarize the array and get certain statistics easily is valuable.

One such statistic is the product of all numbers in an array.

We can get the product of all numbers in an array easily in JavaScript. To get the product of numbers in an array, we can use a for loop and multiply each number by the cumulative product up to that point.

Here again is our function to multiply all elements of an array:

function multiplyArray(arr){
  var total = arr[0];
  for( var i=1; i<arr.length; i++ ){
    total = total * arr[i];
  }
  return total;
};

Hopefully this article has been useful for you to learn how to use JavaScript to multiply all elements in an array.