DexiFunction is a base RC class for representing DEXi aggregation and discretization functions in R.
evaluate(x)A silent wrapper around value(x); it returns NULL when
value(x) fails with an error.
value(x)Return the function value for arguments x, where arguments are
a numeric vector of length equal to att$inputs.
Additionally, arguments of a DexiTabularFunctions$value() must be integer numbers,
and the argument of DexiDiscretizeFunctions$value() must be a single number.
verify()Check the correctnes of this function object and its fields.
Result: error() or TRUE.
DEXi functions are generally associated with aggregate attributes. For some aggregate attribute att,
att$funct defines the mapping from values of att$inputs to values of att.
DexiFunction is a base class that defines fields and methods common to all functions:
method value(x): returns the function value for arguments x. Arguments are
assumed to be a numeric vector of length equal to att$inputs.
method evaluate(x) is a silent wrapper around value(x); it returns NULL when
value(x) fails with an error.
DEXiR implements two other function classes derived from DexiFunction:
DexiTabularFunction and DexiDiscretizeFunction.