MCQs R Vectors 5

1. What is the output of the following R code?
x <- c("a", "b")
as.numeric(x)

c) NA NA (Warning message: NAs introduced by coercion)

TRUE TRUE

1 2

NAN

2. How can one define ‘undefined value’ in R Language?

NaN

Inf

Und

Sup

3. Which of the describe R Language best

Paid

Free

Available for free trial only

Testing

4. How one can define ‘infinity’ in R Language?

NaN

Inf

Sup

Und

5. Identify the wrong statement:

Windows versions of R have other optional help systems also

The help.search( ) (or ??) command allows searching for help in various ways

R is case insensitive as are most UNIX based packages, so A and a are the same symbols and would refer to same variables

$R is used to start the R Program

6. ________ operator is used to create integer sequences.

–

;

7. The following command can be used to print an object “x” in R?

print x

printf(x)

print(x)

cout(x)

8. What is the output of the following R code?
y <- 0:5
vector(y)
y[3]

Error in vectory(y): invalid ‘mode’ argument

9. If a command is incomplete at the end of a line, R will give a different prompt, by default it is _____

–

10. What is the output of the following R code?

r <- 0:10 r[2]

R Frequently Asked Questions