About the structure of variables

Variables are everywhere, let’s understand a bit more about their structures in the R programming language.

Hello! In this post I am going to briefly write about the structure of variables

A variable is a quantity, quality or property that you can measure.

But what is it in practice?

Everytime we create an object, we are also creating a kind of variable

In fact, it’s good to remember that:

\(\color{blue}{\text{"Everything that exists in R is an object."}}\) ~John M. Chambers

So basically we will be dealing with variables all the time!

To understand the 4 main types of variables, you should create the following objects in your workspace:

• logical <- TRUE
• character <- "text"
• numeric <- 1
• factor <- as.factor(c(“I”, “Am”, “a”, “factor”))

Each object is interpreted in a different way by the language, let’s use the function class() to understand how each variable behaves:

class()

Type in the following after creating the objects:

class(logical)
class(character)
class(numeric)
class(factor)

You should have the following answers:

[1] "logical"
[1] "character"
[1] "numeric"
[1] "factor"

Each object belongs to a different class, therefore should be treated as such.

What each of these structures means?

logical

• logical (ou lógica): Boolean/binary , it’s always TRUE or FALSE

character

• character (or string): simple text, including symbols and numbers inside of quotation marks "text", "this is a text", "th1s 1s 4ls0 a t3xt".

numeric

• numeric (numérico): Literally numbers. Mathematic operators can be used here.

Remembering that in truth programming languages are just fancy calculators:

• + add
• - subtract
• * multiply
• / divide
• ^ exponentiation

factor

• factor: Numbers or strings (text) ORDERED somehow:

This is a factor:

as.factor(c("I", "am", "a", "factor"))

This is also a factor:

as.factor(c(1, 2, 3, 4))

The word ORDER is the most important one here to define factors

These are the main 4 structures that will appear in your analyses!

Thank you for your time!

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