trajectory help

[darksauce]

just a quick post. u know the cannon rite? when the player types in the angle, the cannon automatically points to the desired angle. But i want it so that the cannon kinda eases/motion-tweens its direction to the given angle. How would this be programmed?

by the way, the wind display does not seem to work. i applied the code to the arrow but it remains static. the code:

onClipEvent (load) {
arrow._rotation = Math.atan2(wind.y, wind.x) / Math.PI * 180;
}

but it still doesnt seem to point in the right direction, no matter where i place it in the stage. help plz