Class unions in package distr defined for internal
purposes; these are OptionalNumeric,
All of these classes are virtual: No objects may be created from them.
Peter Ruckdeschel peter.ruckdeschel@uni-oldenburg.de
These classes are used internally to make available methods or to allow slots of classes to be filled with varying types. In particular
"OptionalNumeric": may contain objects of class "numeric"
or "NULL"; it is used e.g. for slot nuisance of class
"ParamFamParameter", as it may or may not be present but if so
it has to be numeric.
numeric-class,