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You can use the following basic syntax to select all elements that are not in a list of values in R:

!(data %in% c(value1, value2, value3, ...))

The following examples show how to use this syntax in practice.

**Example 1: How to Use “NOT IN” with Vectors**

The following code shows how to select all values in a vector in R that are not in a certain list of values:

#define numeric vector num_data #display all values in vector not equal to 3 or 4 num_data[!(num_data %in% c(3, 4))] [1] 1 2 5 5 6

All values that are **not equal** to 3 or 4 are shown in the output.

Note that we can use the same syntax to select all elements in a vector that are not in a certain list of characters:

#define vector of character data char_data #display all elements in vector not equal to 'A', or 'C' char_data[!(char_data %in% c('A', 'C'))] [1] "B" "B" "D" "D" "D"

All values that are **not equal** to ‘A’ or ‘C’ are shown in the output.

**Example 2: How to Use “NOT IN” with Data Frames**

The following code shows how to select all rows in a data frame in R in which a certain column is not equal to certain values:

#create data frame df frame(team=c('A', 'A', 'B', 'B', 'C', 'C', 'D'), points=c(77, 81, 89, 83, 99, 92, 97), assists=c(19, 22, 29, 15, 32, 39, 14)) #view data frame df team points assists 1 A 77 19 2 A 81 22 3 B 89 29 4 B 83 15 5 C 99 32 6 C 92 39 7 D 97 14 #select all rows where team is not equal to 'A' or 'B' subset(df, !(team %in% c('A', 'B'))) team points assists 5 C 99 32 6 C 92 39 7 D 97 14

Notice that all rows that do not have an ‘A’ or ‘B’ in the team column are returned.

We can also use similar syntax to select all rows in which a certain column is not equal to certain numeric values:

#create data frame df frame(team=c('A', 'A', 'B', 'B', 'C', 'C', 'D'), points=c(77, 81, 89, 83, 99, 92, 97), assists=c(19, 22, 29, 15, 32, 39, 14)) #view data frame df team points assists 1 A 77 19 2 A 81 22 3 B 89 29 4 B 83 15 5 C 99 32 6 C 92 39 7 D 97 14 #select all rows where team is not equal to 'A' or 'B' subset(df, !(points %in% c(89, 99))) team points assists 1 A 77 19 2 A 81 22 4 B 83 15 6 C 92 39 7 D 97 14

Notice that all rows that are not equal to 89 or 99 in the points column are returned.

**Additional Resources**

How to Use %in% Operator in R

How to Subset a Data Frame in R

How to Subset Lists in R