Why would this work in F6, AS1 but not F7, AS2?

I have the following code which "scoots" a MC to a location with elasticity:

Code:

---

slideY = function(mc, dest) {
        mc.onEnterFrame = function() {
                this._Y = slideMc(this, "_Y", dest, .4, .6);
                if (Math.round(this._Y) == [dest]) {
                        trace("slideY done");
                        this.onEnterFrame = undefined;
                }
        };
}
slideMc = function(mc, property, destination, inertia, friction) {
        yspeed = ((puppy._y-destination)*inertia)+(yspeed*friction);
        mc[property] -= yspeed;
        return (mc[property]);
}

---

However this will work fine if I export the swf as Flash 6, ActionScript 1.0, but it will not work as Flash 7, ActionScript 2.0.

Why is this?

This line :

Code:

---

yspeed = ((puppy._y-destination)*inertia)+(yspeed*friction);

---

yspeed traced NAN

You init the variable yspeed there but also use it instantly, that messes it up i guess.

You're exactly right. Initializing the yspeed vairaible beforehand solves the problem in v7, AS2.

Thanks so much.

no problem :D