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Arithmetic with R

In its most basic form, R can be used as a simple calculator. Consider the following arithmetic operators:

• Addition: +
• Subtraction: -
• Multiplication: *
• Division: /
• Exponentiation: ^
• Modulo: %%

The last two might need some explaining:

• The ^ operator raises the number to its left to the power of the number to its right: for example 3^2 is 9.
• The modulo returns the remainder of the division of the number to the left by the number on its right, for example 5 modulo 3 or 5 %% 3 is 2.

With this knowledge, follow the instructions to complete the exercise.

Instructions

100 XP

Instructions

100 XP

• Type 2^5 in the editor to calculate 2 to the power 5.
• Type 28 %% 6 to calculate 28 modulo 6.
• Submit the answer and have a look at the R output in the console.
• Note how the # symbol is used to add comments on the R code. 

Variable assignment

A basic concept in (statistical) programming is called a variable.

A variable allows you to store a value (e.g. 4) or an object (e.g. a function description) in R. You can then later use this variable's name to easily access the value or the object that is stored within this variable.

You can assign a value 4 to a variable my_var with the command

my_var <- 4

Instructions

100 XP

Over to you: complete the code in the editor such that it assigns the value 42 to the variable x in the editor. Submit the answer. Notice that when you ask R to print x, the value 42 appears.

• script.R

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# Assign the value 42 to x

x <- 

 

# Print out the value of the variable x

x

• R Console

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