auxiliary classes; may contain either a Parameter or NULL, resp. a matrix or NULL cf. J. Chambers, "green book".
"OptionalParameter" is a virtual Class: No objects may be created from it;
"OptionalMatrix" is a class generated by setClassUnion() so may contain NULL or any matrix
No methods defined with class "OptionalParameter" in the signature.
Thomas Stabla statho3@web.de,
Florian Camphausen fcampi@gmx.de,
Peter Ruckdeschel peter.ruckdeschel@uni-oldenburg.de,
Matthias Kohl Matthias.Kohl@stamats.de
Parameter-class, AbscontDistribution-class