Using fda - bruto

Dear All,

I would like to use the "fda"-function in combination with 
"method=bruto" in the mda library. But all my attempts failed. I tried 
several syntaxes but only got nonsense or a computer-crash. So I don't 
know, if I'm totally on the wrong trip or if it's bug. Can anyone give 
me a working syntax example for a simple data-package like "iris"?

Thanks in advance for any hint!

ciao,

Ulrich Marckmann