Simple easing without extrenal API

import fl.transitions.*;
import fl.transitions.easing.*;
 
//More info
//http://livedocs.adobe.com/flash/9.0/ActionScriptLangRefV3/fl/transitions/easing/package-detail.html
 
stage.frameRate = 31;
 
var box:Sprite = new Sprite();
box.graphics.beginFill(Math.random() * 0xFFFFFF);
box.graphics.drawRect(0, 0, 100, 350);
box.graphics.endFill();
box.x = 50;
box.y = 10;
addChild(box);
 
var startValue:Number = box.x;
var finishValue:Number = 400;
var duration:Number = 3;
var myTween:Tween = new Tween(box, "x", Strong.easeOut, startValue, finishValue, duration, true);
myTween.looping = true;