How to Select Columns by Name Using dplyr


You can use the following methods to select columns of a data frame by name in R using the dplyr package:

Method 1: Select Specific Columns by Name

df %>% select(var1, var3)

Method 2: Select a Range of Columns by Name

df %>% select(var1:var3)

Method 3: Select All Columns Except Certain Columns

df %>% select(-c(var1, var3))

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

#create data frame
df <- data.frame(points=c(1, 5, 4, 5, 5, 7, 8),
                 rebounds=c(10, 3, 3, 2, 6, 7, 12),
                 assists=c(5, 5, 7, 6, 7, 9, 15),
                 blocks=c(1, 1, 0, 4, 3, 2, 10))

#view data frame
df

  points rebounds assists blocks
1      1       10       5      1
2      5        3       5      1
3      4        3       7      0
4      5        2       6      4
5      5        6       7      3
6      7        7       9      2
7      8       12      15     10

Example 1: Select Specific Columns by Name

We can use the following code to select only the points and assists columns:

library(dplyr)

#select only points and assists columns
df %>% select(points, assists)

  points assists
1      1       5
2      5       5
3      4       7
4      5       6
5      5       7
6      7       9
7      8      15

Notice that only the points and assists columns are returned.

Example 2: Select a Range of Columns by Name

We can use the following code to select all columns between the names points and assists.

library(dplyr)

#select all columns between points and assists
df %>% select(points:assists)

  points rebounds assists
1      1       10       5
2      5        3       5
3      4        3       7
4      5        2       6
5      5        6       7
6      7        7       9
7      8       12      15

A range of columns is returned, starting with the points column and ending with the assists column.

Example 3: Select All Columns Except Certain Columns

We can use the following code to select all columns except the points and assists columns.

library(dplyr)

#select all columns except points and assists columns
df %>% select(-c(points, assists))

  rebounds blocks
1       10      1
2        3      1
3        3      0
4        2      4
5        6      3
6        7      2
7       12     10

All of the columns are returned except the points and assists columns.

Note: You can find the complete documentation for the select function in dplyr here.

Additional Resources

The following tutorials explain how to perform other common operations in dplyr:

How to Select Columns by Index Using dplyr
How to Select the First Row by Group Using dplyr

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