There are 2 ways of doing AngularJs filters, one in the HTML using {{}} and one in actual JS files...
You can solve you problem by using :
{{ Expression | orderBy : expression : reverse}}
if you use it in the HTML or use something like:
$filter('orderBy')(yourArray, yourExpression, reverse)
The reverse is optional at the end, it accepts a boolean and if it's true, it will reverse the Array for you, very handy way to reverse your Array...