Alpha Fading with Actionscript

I’ve been trying to put together a function that I can reference through various symbols in a movie to fade their alpha properties. So far all I’ve found is code that forces me to reference the specific symbol in the function, however I have to do this to a BUNCH of symbols over different periods within my timeline, part of which will be triggered by a loaded movie.

Does anyone have a function that will fade up or down that can sit on the _root. and be referenced by any symbol whenever needed?

If this doesn’t make sense, please let me know, I will clarify!

Thanks in advance;
.mahchevoi