[FMX]Function random movement

programming flash
1

I have the following clipEvent on a movieclip called square:

onClipEvent (enterFrame) {
xmove = (xpos-this._x)/5;
this._x += xmove;
}

And the following framecode in the same keyframe as square:

_root.square.xpos = Math.round(Math.random()*550);

Now I want to use this information in a function so I can control more than just one clip.

How should this function look like?