Pos for a derma panel

So this is out of curiosity, what would be like the exact center of your screens position? I am just wondering because find an exact place for the derma panel is easy yes, but it is just a little more work to find an exact place. So my question is what would be a good pos for a derma panel being exactly in the middle?

local panelw = 640
local panelh = 480

dermaframe:SetSize( panelw, panelh )
-- you can call dermapanel:Center() to center it
-- or you can do this math shit
dermaframe:SetPos( (ScrW() - panelw) / 2, (ScrH() - panelh) / 2 )
-- ScrW() grabs the window's width and ScrH() grabs its height
-- If you're only trying to center the window then don't do this math shit, just call dermaframe:Center()

Thank you very much timz9. I didn’t think about setting the pos dependent on the users screen. Thanks again very much!