Adobe Extending Flash Professional CS5 - Manual (Page 366)

344 EXTENDING FLASH PROFESSIONAL
Matrix object
Last updated 5/2/2011
Usage
matrix.ty
Description
Property; a floating-point value that specifies the y-axis location of a symbol’s registration point or the center of a
shape. It defines the y translation of the transformation.
You can move an object by setting the matrix.tx and matrix.ty properties.
Example
See the
matrix.tx example.