Coordinate sorting example

coordinates.js

var zip = function(array1, array2) {
    return array1.map(function(v, i) {
        return {x: v,
                y: array2[i]};
    });
};

var xs = [8,7,6,5];
var ys = [4,3,2,1];

var coordinates = zip(xs, ys);
console.log(coordinates);

var compareCoordinates = function(c1, c2) {
    return c1.x - c2.x;
};

var sortedCoordinates = coordinates.sort(compareCoordinates);
console.log(sortedCoordinates);