Suppose, we have an array of arrays of Integers like this −
const arr = [ [1, 2, 3], [4, 5, 6] ];
We are required to write a JavaScript function that takes in one such array of arrays. The function should calculate the average for each subarray separately and then return the sum of all the averages.
Therefore, for the above array the output should be −
2 + 5 = 7
Example
The code for this will be −
const arr = [
[1, 2, 3],
[4, 5, 6]
];
const sumAverage = (arr = []) => {
const average = arr.reduce((acc, val) => {
const total = val.reduce((total, num) => total += num, 0);
return acc += total / val.length;
}, 0);
return Math.round(average);
};
console.log(sumAverage(arr));Output
And the output in the console will be −
7