After Effects: centering Layer by Expression

Question

Iam trying zo position a Layer by expression. I need exacly the center of the Layer.

w=thisComp.width; //x
h=thisComp.height;//y
w2=w/2;
h2=h/2;
??

Answer 1

Ok i think i got it!

var w=thisComp.width;
var h=thisComp.height;
var w2=w/2;
var h2=h/2;
[w2,h2]