R Programming Practice Test 5

1. CRAN package ecosystem has more than ______ packages.

6000

8000

5000

4000

2. What are the different types of sorting algorithms available in R language?

Bubble

Selection

Merge

All sorts

3. R has ________ statements that provide explicit looping.

4. What will be the output of the following R code snippet?

 > paste("a", "b", se = ":")

"a+b"

"a=b"

"a b :"

none of the mentioned

5. Point out the correct statement?

Functions are often used to encapsulate a sequence of expressions that need to be executed numerous times

Functions are also often written when code must be shared with others or the public

Writing functions is a core activity of an R programmer

All of the mentioned

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

> f <- function(num = 1) {
+        hello <- "Hello, world!\n"
+        for(i in seq_len(num)) {
+                cat(hello)
+         }
+         chars <- nchar(hello) * num
+         chars
+ }
> f()

Hello, world!
[1] 15

Hello, world!
[1] 14

Error

Hello, world!
[1] 16

7. Two vectors M and N are defined as M <- c(3, 2, 4) and N <- c(1, 2). What will be the output of vector Z that is defined as Z <- M*N.

Z <- (3, 2, 4)

Z <- (3, 6, 4)

Z <- (3, 4, 4)

Z <- (3, 4, 5)

8. Which of the following is valid syntax for if else statement in R?

if(<condition>) {
          ## do something
}
elseif {
          ## do something else
}

if(<condition>) {
          ##& do something
}
else {
          ##@ do something else
}

if(<condition>) {
          ## do something
}
else {
          ## do something else
}

if(<condition>) {
          ## do something
}
else if {
          ## do something else
}

9. What is the memory limit in R for 64 bit system?

16TB

9TB

10TB

8 TB

10. Which of the following code will print NULL?

> args(paste)

> args(pastebin)

> arg(bin)

> arg(paste)