Enough with the `if (a > b) { } else if (a < b) { } else { }` stuff, OK? If you've got numbers, you can sort with a one-liner as follows...

one-liner-array-sorts.js

var arr = [10, 5, 6, 1, -2, 28];

function ascending(a, b){
    return ( (a - b) / Math.abs(a - b) ) || 0;
}

function descending(a, b){
    return ( (b - a) / Math.abs(b - a) ) || 0;
}

arr.sort(ascending);
// [-2,1,5,6,10,28]

arr.sort(descending);
// [28,10,6,5,1,-2]