R中的签名是什么意思？

Question

HI I was reading this doc and it says

rules-class

coerce signature(from = "rules", to = "data.frame"); represents the set of rules as a data.frame

Does this mean I can write code this?

coerce(object_of_rules_class, from = 'rules', to = 'data.frame')

What does signature mean - some simple example please? Thanks-

Answer 1

I believe the best definition is provided in "How S4 Methods Work" by J. Chambers, p.2 : a signature is "a named list of classes, with the names corresponding to the formal arguments of the function". That is to say, it specifies the classes of the arguments.

If I understood it correctly, the code you mentioned means the function will coerce the passed argument (an object of class 'rules') into an object of class 'data.frame' before actually being used by the function.