ActionScript 2.0 Language Reference - Adobe Help and Support

The rotate() method alters the a, b, c, and d properties of the Matrix object. In matrix
notation this is shown as follows:
Availability: ActionScript 1.0; Flash Player 8
Parameters
angle:Number - The rotation angle in radians.
Example
The following example shows how the rotate() method rotates rectangleMc 30° clockwise.
Applying myMatrix to rectangleMc resets its _x value, leaving you to reset it to 100
manually.
import flash.geom.Matrix;
import flash.geom.Transform;
var myMatrix:Matrix = new Matrix();
trace(myMatrix.toString()); // (a=1, b=0, c=0, d=1, tx=0, ty=0)
var degrees:Number = 30;
var radians:Number = (degrees/180) * Math.PI;
myMatrix.rotate(radians);
trace(myMatrix.toString()); // (a=0.866025403784439, b=0.5, c=-0.5,
d=0.866025403784439, tx=0, ty=0)
var rectangleMc:MovieClip = createRectangle(20, 80, 0xFF0000);
trace(rectangleMc._x); // 0
rectangleMc._x = 100;
trace(rectangleMc._x); // 100
var rectangleTrans:Transform = new Transform(rectangleMc);
rectangleTrans.matrix = myMatrix;
trace(rectangleMc._x); // 0
rectangleMc._x = 100;
trace(rectangleMc._x); // 100
788 ActionScript classes