Free Printable The Basics of R

Worksheets

The Basics of R

Total questions: 21

Worksheet time: 8mins

Name

Class

Date

What is this an icon of?

slack.png

R Project

R engine

R Studio

What extension will an R script have?

.Rscript

.Rproj

.Rmd

Which key autocompletes the existing object or function name when you start typing in R?

"->"

Shift

Tab

Escape

Which of the following is an absolute local path?

C:/users/me/Desktop/DigitalMethods/data/SAFI_clean.csv

data/SAFI_clean.csv

https://ndownloader.figshare.com/files/11492171

here/SAFI_clean.csv

Which command below will create a new object called interviews?

interviews <- c(1,2,3)

interviews[interviews =="yes"]

create.dir(interviews)

interviews <- NULL

What does .Rproj extension denote?

It is the file extension for Rmarkdown document.

It designates an R working directory for R session and makes starting new research projects in R easier.

It is a file that needs to be active for R to work.

It is the file extension for R script.

What does getwd() do in R?

Displays the path to your current working directory

Lists the contents of the current directory

Sets the working space to the current directory

Sets the path to the current directory

What is the data type of the 'interviews' object: interviews <- c(1, "a", TRUE, "TRUE")

Logical

Numeric

Character

Complex

What will the following command rooms[!is.na(rooms)] do?

Eliminate all missing values from the rooms object

Extract and display those elements of rooms which contain missing values

Create a new rooms object without missing values

Display those elements of rooms object which are not missing values (NAs).

10.

Which of the following are good names for your digital objects in R?

My_beautiful_object

My.beautiful.object

My beautiful object

My#Beautif$lobj8ct

MyBeautifulObject

11.

How will R interpret the following statement? 'round()'

As a Subset of an Object called 'round'

As a Vector

As a Function

As a "Plot a Circle" command

12.

How do you install the tidyverse package in R?

install.packages(tidyverse)

install.tidyverse()

library(tidyverse)

install.packages("tidyverse")

13.

What does the following code do: read_csv("data/SAFI_clean.csv")

Creates SAFI_clean.csv spreadsheet in the data folder

Loads SAFI_clean.csv to R Studio with ephemeral output in the console

Deletes the SAFI_clean.csv in the data folder

Creates a new object called SAFI_clean in R Studio environment

14.

If I execute the expression x <- 4 in R, what will be the output of running `class(x)' ?

numeric

-4

"4"

15.

What is the class of the object defined by x <- c(4, TRUE)?

numeric

logical

integer

a vector containing values "4", "TRUE"

16.

If I have two vectors x <- c(1,3, 5) and y <- c(3, 2, 10), what is produced by the expression c(x, y)?

a 3 by 2 numeric matrix

a vector with three elements, containing the numbers 4,5,15

a vector with six elements containing the numbers 1,3,5,3,2,10

a vector with two elements 9, 15

17.

A key property of vectors in R is that

elements of a vector all must be of the same class

vectors can be two-dimensional

each element can be of different class

vectors can contain both logical and either numeric or character values

18.

Suppose I have a vector x <- 1:4 and a vector y <- 2. What is produced by the expression x * y?

a numeric vector with elements 3, 4, 5, 6.

a numeric vector with elements 1,4,2

a numeric vector with elements 1,2,3,4,2

a numeric vector with elements 2, 4, 6, 8.

19.

Suppose you have a vector x <- 1:4 and a vector y <- 2:3. What is produced by the expression x+y ?

3,5,5,7

1,2,3,4,2,3

1,4,2,3

2,8,3,12

20.

If an incomplete command is executed, R console will show the following prompt:

21.