How to Select Columns Containing a Specific String in R


You can use the following functions from the dplyr package in R to select columns that contain a specific string:

Method 1: Select Columns that Contain One Specific String

df %>%
  select(matches("string1"))

Method 2: Select Columns that Contain One of Several Strings

df %>%
  select(matches("string1|string2|string3"))

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

#create data frame
df <- data.frame(mavs=c(12, 10, 14, 19, 22, 25, 29),
                 cavs=c(22, 41, 14, 15, 15, 19, 22),
                 hornets=c(8, 8, 12, 14, 15, 13, 12),
                 spurs=c(10, 12, 12, 16, 22, 28, 30),
                 nets=c(9, 7, 10, 22, 28, 23, 25))

#view data frame
df

  mavs cavs hornets spurs nets
1   12   22       8    10    9
2   10   41       8    12    7
3   14   14      12    12   10
4   19   15      14    16   22
5   22   15      15    22   28
6   25   19      13    28   23
7   29   22      12    30   25

Example 1: Select Columns that Contain One Specific String

The following code shows how to use the matches() function to select only the columns that contain the string “avs” somewhere in their name:

library(dplyr)

#select all columns that contain "avs" in the name
df %>%
  select(matches("avs"))

  mavs cavs
1   12   22
2   10   41
3   14   14
4   19   15
5   22   15
6   25   19
7   29   22

Only the columns that contain “avs” in the name are returned.

In this case, “mavs” and “cavs” are the only columns that are returned.

Example 2: Select Columns that Contain One of Several Strings

The following code shows how to use the matches() function to select only the columns that contain “avs” or “ets” somewhere in their name:

library(dplyr)

#select all columns that contain "avs" or "ets" in the name
df %>%
  select(matches("avs|ets"))

  mavs cavs hornets nets
1   12   22       8    9
2   10   41       8    7
3   14   14      12   10
4   19   15      14   22
5   22   15      15   28
6   25   19      13   23
7   29   22      12   25

Only the columns that contain “avs” or “ets” in the name are returned.

Note that the vertical bar ( | ) is the “OR” operator in R.

Feel free to chain together as many of these “OR” operators as you’d like to select columns that contain one of several different strings.

Additional Resources

The following tutorials explain how to perform other common tasks using dplyr:

How to Select Columns by Name Using dplyr
How to Select Columns by Index Using dplyr
How to Use select_if with Multiple Conditions in dplyr

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