R Programming Practice Test 2

1. What will be the output of the following R function?

Sys.time()

Tomorrow date and time

Present date and time

Some date

Yesterday date and time

2. Files containing R scripts ends with extension ____________

.SP

.Rp

3. The open source _________ software is available for Unix, Linux, and Windows platforms.

Rserve

Dserve

BServe

CServe

4. Point out the correct statement?

Number Inf represents infinity in R

The value NaN represents undefined value

“raw” objects are commonly used directly in data analysis

NaN can also be thought of as a missing value

5. The longer programs are called ____________

Structures

Data

Files

Scripts

6. What will be the output of the following R code?

> x <- c("a", "b", "c")
> as.logical(x)

6 8 9

a b c

0 1 2

NA NA NA

7. Modification in Dundas BI is done ______________

Directly

Indirectly

Need access to Server

Not known

8. Numbers in R are generally treated as _______ precision real numbers.

double

single

real

imaginary

9. What will be the output of the following R function?

cat("Everybody", "is", "a", “warrior”,sep="*")

Everybody", "is", “a” , "warrior

Everybody*is*a*warrior

“Everybody", "is", “a” , "warrior”

“Everybody*is*a*warrior”

10. In the expression x <- 4 in R, what is the class of 'x' as determined by the `class()' function?

Word

Numeric

Integer

Character