# Vector, Array, List and Data Frame in R

Vector, Array, List and Data Frame are 4 basic data types defined in R. Knowing the differences between them will help you use R more efficiently.

1. Vector

All elements must be of the same type.

For example, the following code create two vectors.

name <- c("Mike", "Lucy", "John")
age <- c(20, 25, 30)

2. Array & Matrix

Matrix is a special kind of vector. A matrix is a vector with two additional attributes: the number of rows and the number of columns.

> x <- matrix(c(1,2,3,4), nrow=2, ncol=2)
> x
[,1] [,2]
[1,]    1    3
[2,]    2    4

Similar to matrix, but arrays can have more than two dimensions.

3. List

List can contain elements of different types.

> y <- list(name="Mike", gender="M", company="ProgramCreek")
> y
\$name
[1] "Mike"
\$gender
[1] "M"
\$company
[1] "ProgramCreek"

4. Date Frame

A data frame is used for storing data tables. It is a list of vectors of equal length.

For example, you can create a date frame by using the following code:

> name <- c("Mike", "Lucy", "John")
> age <- c(20, 25, 30)
> student <- c(TRUE, FALSE, TRUE)
> df = data.frame(name, age, student)
> df
name age student
1 Mike  20    TRUE
2 Lucy  25   FALSE
3 John  30    TRUE
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• Stephen Boesch

• mimi

“matrix is a special kind of vector.” this statement is not correct.
matrix is ​​a larger category than vector. It is a kind of inclusive relationship.

• renceokgobja

Thanks for that. Makes sense now

• Krishna Praveen

if you want it the second way you have to add another argument “byrow=TRUE” .By default r takes column wise

• renceokgobja

x <- matrix(c(1,2,3,4), nrow=2, ncol=2)
gives

> x
[,1] [,2]
[1,] 1 3
[2,] 2 4

Why can’t it be

> x
[,1] [,2]
[1,] 1 2
[2,] 3 4

Does R implicitly assign columns first?

• gamebusterz

Clear and short explanation. Thanks