*25*

You can use one of the following methods to subset a data frame by factor levels in R:

**Method 1: Subset by One Factor Level**

#subset rows where team is equal to 'B'df_sub =='B', ]

**Method 2: Subset by Multiple Factor Levels**

#subset rows where team is equal to 'A' or 'C' df_sub %in%c('A', 'C'), ]

The following examples show how to use each of these methods in practice with the following data frame in R:

#create data frame df frame(team=factor(c('A', 'A', 'B', 'B', 'B', 'C')), points=c(22, 35, 19, 15, 29, 23)) #view data frame df team points 1 A 22 2 A 35 3 B 19 4 B 15 5 B 29 6 C 23

**Method 1: Subset by One Factor Level**

The following code shows how to create a new data frame that subsets by the rows where the value in the **team** column is equal to â€˜Bâ€™:

#subset rows where team is equal to 'B' df_sub == 'B', ] #view updated data frame df_subteam points 3 B 19 4 B 15 5 B 29

Notice that the new data frame only contains rows where the value in the **team** column is equal to â€˜Bâ€™.

**Example 2: Subset by Multiple Factor Levels**

The following code shows how to create a new data frame that subsets by the rows where the value in the **team** column is equal to â€˜Aâ€™ or â€˜Câ€™:

#subset rows where team is equal to 'A' or 'C' df_sub %in% c('A', 'C'), ] #view updated data frame df_subteam points 1 A 22 2 A 35 6 C 23

Notice that the new data frame only contains rows where the value in the **team** column is equal to â€˜Aâ€™ or â€˜Câ€™.

Using this syntax, you can include as many factor levels as youâ€™d like in the vector following the** %in%** operator to subset by even more factor levels.

**Related:** How to Use %in% Operator in R (With Examples)

**Additional Resources**

The following tutorials explain how to perform other common tasks in R:

How to Convert Factor to Numeric in R

How to Convert Factor to Character in R

How to Reorder Factor Levels in R