R

Question 1

Rules for naming objects in R

Answer 1

• Names can include letters, numbers, periods (.), and underscores(_)
• They must begin with a letter or a period. If period it can’t be followed by digit.
• Reserved words like if, else, TRUE, FALSE, NA, etc., can’t be used. To find out
  about reserved word in R, you can type
  > ?reserved

Question 2

What does the # do in R?

Answer 2

It is a naming method to add comments are lines in code to explain, notes, descriptions that are not executed as part of the program.

Question 3

What is a function?

Question 4

Functions generic syntax

Answer 4

function_name (argument1,…,argument = defaultt…)

Question 5

What does ? do

Answer 5

if you need help on info about a function

Question 6

Basic data types of R

Answer 6

Numeric data (double, integer)
String data (character)
Logical data (logical)

Question 7

&

Answer 7

Logical operator AND
returns TRUE if both conditions are TRUE, otherwise returns FALSE.

Question 8

|

Answer 8

Logical Operator for OR
Returns true if at least one of the conditions is TRUE, or otherwise returns FALSE.

Question 9

!

Answer 9

NOT negates the logical value of a condition.

Question 10

Precedence in logical operator

Answer 10

1) NOT 2) AND 3) OR

Question 11

Vectors

Answer 11

fundamental data structure that allows you to STORE A SEQUENCE OF ELEMENTS OF THE SAME DATA TYPE.

Question 12

c()

Answer 12

function combine to create a vector by combining elements of the same type.

Question 13

Types of vectors

Answer 13

Numeric vectors: Contains numeric values (integers or decimals).
Character Vectors: Holds text or strings.
Logical Vectors: Consists of TRUE or FALSE values.

Question 14

What happens when you compare a vector and an atomic value using operator like > < ==?

Answer 14

Each element within the vector is INDIVIDUALLY compared to the atomic value

Question 15

length()

Answer 15

determine the number of elements in an object

Question 16

Subsetting

Answer 16

Element extraction from a vector. Allows you to extract specific elements or subsets of elements from a vector based on different conditions or indices.

Question 17

name [index/indices]

Answer 17

subsetting

Question 18

which()

Answer 18

indexes of TRUE’s of the vector in its argument

Question 19

tidyverse

Answer 19

A library that consists of a set of R packages tailored for data science tasks

Question 20

Data.frame()

Answer 20

Data Frame in Base R used to store tabular data like spreadsheets. Like matrices, they have rows and columns. Unlike matrices, they can store
different classes of objects in each column.