You need the ease or you want to make the expression. Because if what you are looking for is an easy way to ease(omg, how this sounds :))) you can check this out. It's "name your own price", so you can download it free, and then pay the author if you feel like they made your life easier(i think this script will). Plus, this script is not binary encrypted, so you can also see the code. Maybe you can find your answer(or maybe more than what you are looking for) in his code. I have seen it, very clean and well commented.