Question

You can check to see whether an R object is NULL with the _________ function. (a) is.null() (b) is.nullobj() (c) null() (d) as.nullobj() I got this question in homework. The origin of the question is Functions topic in portion Control Structures, Functions, Scoping Rules, Loop Functions and Debugging of R Programming Select the correct answer from above options

Answer 1

Right answer is (a) is.null() To elaborate: It is sometimes useful to allow an argument to take the NULL value, which might indicate that the function should take some specific action.