## Vectors

Vectors are defined as a sequence of data elements of a certain data type. Below are 3 different types of vectors as examples

### Numeric Vectors

Num_Vec <- c(3,6,9)

[1] 3.2 6.0 9.0

### Logical Vectors

Log_Vec <- c(“TRUE”, “TRUE”, “FALSE”)

[1] "TRUE" "TRUE" "FALSE"

### Character Vectors

Char_Vec <- c(“Steve”, “Sarah”, “Tim”)

[1] "Steve" "Sarah" "Tim"

## Data Frames

A data frame is a named list of vectors where the length of each vector is must be the same.

df <- data.frame(Num_Vec, Log_Vec, Char_Vec)

```
## Num_Vec Log_Vec Char_Vec
## 1 3 TRUE Steve
## 2 6 TRUE Sarah
## 3 9 FALSE Tim
```

## List

A list is a vector of data structures

mylist <- list(Num = Num_Vec,

Logic = Log_Vec,

Char = Char_Vec)

```
## $Num
## [1] 3 6 9
##
## $Logic
## [1] "TRUE" "TRUE" "FALSE"
##
## $Char
## [1] "Steve" "Sarah" "Tim"
```

## Matrix

Matrix is two-dimensional data structures where all data types must be the same.

Below is an example of a matrix where we set the number of data elements to 20 where we have 5 columns each with 4 rows of data.

mat <- matrix(1:20, 4,5)

```
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 5 9 13 17
## [2,] 2 6 10 14 18
## [3,] 3 7 11 15 19
## [4,] 4 8 12 16 20
```