A function value table
(object of class "fv", see fv.object)
is a convenient way of storing and plotting
several different estimates of the same function.
The default behaviour of plot(x) for a function value table
x is determined by a formula
associated with x called its plot formula.
See plot.fv for explanation about these formulae.
The function formula.fv is a method for the generic command
formula. It extracts the plot formula associated with
the object.
The function formula<- is generic. It changes the formula
associated with an object.
The function formula<-.fv is the method for formula<-
for the class "fv". It changes the plot formula associated with
the object.