This function is an S Version 3 generic (see Methods);
method functions can be written to handle specific
S Version 3 classes of data. Classes that already
have methods for this function include
data.frame,
bdFrame,
formula,
lm,
bdLm, and
terms.
formula(object) as.formula(object)
~ operator),
or an object that defines such an expression, such as a fitted model
or a
terms object.
"formula", essentially just the call to
~.
The
as.formula function differs only in that it will preserve
the full class attribute of an object that inherits from class
"formula".
sqrt(skips) ~ . #or, equivalently formula(sqrt(skips) ~ .) formula(fuel.fit) # find the formula