Contents

Apart from the regular arithmetic, logical and relational operators, R has some miscellaneous operators. In this tutorial you will learn about the *miscellaneous operators* in R with examples.

## Miscellaneous Operators in R

In R, miscellaneous operators are used for special purposes like data frame column selection, generating sequences, model formula, matrix multiplication, etc. Following symbols are used as miscellaneous operators in R programming language:

Operator Symbols |
Operation |
Example |
---|---|---|

`$` |
Data frame column selection | `df$name` |

`$` |
Named list selection | `lst$name` |

`:` |
Sequence generation | `1:5` |

`%in%` |
Element belongs to a vector | `5 %in% x` |

`%*%` |
Matrix Multiplication | `A %*% B` |

`~` |
Model formula | `x ~ y` |

## Examples of miscellaneous Operators in R

### Data frame column selection (`$`

)

The `$`

operator is used to access the column of a data frame or named list. To know more about data frames in R check our post data frames in R.

```
## trees is a built-in data frame
data("trees")
# To access the Girth column of trees
trees$Girth
```

```
[1] 8.3 8.6 8.8 10.5 10.7 10.8 11.0 11.0 11.1 11.2 11.3 11.4 11.4 11.7 12.0
[16] 12.9 12.9 13.3 13.7 13.8 14.0 14.2 14.5 16.0 16.3 17.3 17.5 17.9 18.0 18.0
[31] 20.6
```

Note that to access the variables of data frame directly with the names you can use the `attach()`

function.

Using `attach()`

function the data frame is attached to the R search path and the variables in the data frame can be accessed by simply giving their names.

```
attach(trees)
Girth
```

```
[1] 8.3 8.6 8.8 10.5 10.7 10.8 11.0 11.0 11.1 11.2 11.3 11.4 11.4 11.7 12.0
[16] 12.9 12.9 13.3 13.7 13.8 14.0 14.2 14.5 16.0 16.3 17.3 17.5 17.9 18.0 18.0
[31] 20.6
```

### Named list selection (`$`

)

The `$`

operator is used to access components of named list. To know more about lists in R check our post lists in R.

```
mylist <-list(Number =10:14,
Fruit =c("Apple","Orange","Banana") )
```

The elements of component `Number`

from the list `mylist`

can be accessed using `mylist$Number`

.

```
# to access the elements of component Number
mylist$Number
```

`[1] 10 11 12 13 14`

The elements of component `Fruit`

from the list `mylist`

can be accessed using `mylist$Fruit`

.

```
# to access the elements of component Fruit
mylist$Fruit
```

`[1] "Apple" "Orange" "Banana"`

### Sequence Operator (`:`

)

The sequence operator `:`

is used to generate regular sequence.

```
# generate sequence from 1 to 5
1:5
```

`[1] 1 2 3 4 5`

```
# generate sequence from 8 to 4
8:4
```

`[1] 8 7 6 5 4`

To know more about sequence operator and examples of sequence operator check our post about Generating vectors using `:`

operator

### Examples of `%in%`

operator

The `%in%`

is a binary operator, which returns a logical vector indicating if there is a match or not for it left operand.

```
a <- 6
b <- c(4,6,16,6)
a %in% b
```

`[1] TRUE`

`b %in% a`

`[1] FALSE TRUE FALSE TRUE`

### Example of `%*%`

Operator

The operator `%*%`

is used for actual matrix multiplication of two matrices, if they are conformable.

`A <- matrix(c(1, 2, 3, 4), nrow = 2)`

To get the matrix multiplication of `A`

with `A`

use below code:

`A %*% A # Matrix Multiplication`

```
[,1] [,2]
[1,] 7 15
[2,] 10 22
```

To know more about matrix in R and various functions related to matrices check our post matrix in R.

The operator `*`

perform element-wise matrix multiplication whereas the operator `%*%`

perform actual matrix multiplication.

### Example of `~`

operator

The `~`

(tilde) operator is used to separate the left- and right-hand sides in a model formula.

```
x <- c(12, 10, 8, 16, 6)
y <- c(15, 8, 11, 14, 7)
```

To fit a linear regression model of `y`

on `x`

, we use `~`

operator in `lm()`

function to specify the model formula.

```
model <- lm(y ~ x)
model
```

```
Call:
lm(formula = y ~ x)
Coefficients:
(Intercept) x
3.6216 0.7095
```

## Endnote

In this tutorial you learned about some miscellaneous operators used in R and how to use these operators in R.

To learn more about other operators in R, please refer to the following tutorials:

Assignment operators in R

Arithmetic operators in R

Relational operators in R

Logical operators in R

Precendence of Operators in R

Operators in R

Hopefully you enjoyed learning this tutorial on miscellaneous operators in R. Hope the content is more than sufficient to understand miscellaneous operators in R.