Aggregating object values of JavaScript arrays?

Question

In JavaScript, given n number of arrays as input in this format: (n=2)

array1:
[{x: 1, y: 5},{x: 2, y: 3},{x: 3, y: 6}]

array2:
[{x: 1, y: 2},{x: 2, y: 6},{         


        

Answer 1

Benchmark Example

Note that the mixed code is faster followed by loops followed by native/underscore.

function createOutput(arr1, arr2, arr3 /*, ... */) {
    return Array.prototype.reduce.call(arguments, function (prev, curr) {
        return prev.map(function(val, index) {
            return {
                x: val.x,
                y: val.y + curr[index].y
            }
        });
    });
}

Assumes arrays are sorted and contain all values of x in order 1..n with no gaps.

Kind of requires ES5. This can be swapped out for _ which gives this kind of functionality in a cross browser manner.

With underscore it is

function createOutput() {
    return _.reduce(arguments, function (memo, arr) {
        return _.map(memo, function(val, index) {
            return { x: val.x, y: val.y + arr[index].y };
        });
    });
}