title | tags |
---|---|
weightedAverage |
math,array,intermediate |
Returns the weighted average of two or more numbers.
- Use
Array.prototype.reduce()
to create the weighted sum of the values and the sum of the weights. - Divide them with each other to get the weighted average.
const weightedAverage = (nums, weights) => {
const [sum, weightSum] = weights.reduce(
(acc, w, i) => {
acc[0] = acc[0] + nums[i] * w;
acc[1] = acc[1] + w;
return acc;
},
[0, 0]
);
return sum / weightSum;
};
weightedAverage([1, 2, 3], [0.6,0.2,0.3]); // 1.72727