You can use the following basic syntax in dplyr to select data frame columns by index position:
#select columns in specific index positions df %>% select(1, 4, 5) #exclude columns in specific index positions df %>% select(-c(1,2))
The following examples show how to use this syntax in practice with the following data frame:
#create data frame df frame(team=c('A', 'B', 'C', 'D', 'E'), points=c(99, 90, 86, 88, 95), assists=c(33, 28, 31, 39, 34), rebounds=c(30, 28, 24, 24, 28), blocks=c(14, 19, 22, 18, 15)) #view data frame df team points assists rebounds blocks 1 A 99 33 30 14 2 B 90 28 28 19 3 C 86 31 24 22 4 D 88 39 24 18 5 E 95 34 28 15
Example 1: Select Columns in Specific Index Positions
The following code shows how to select columns in specific index positions:
library(dplyr) #select columns in position 1, 4, and 5 df %>% select(1, 4, 5) team rebounds blocks 1 A 30 14 2 B 28 19 3 C 24 22 4 D 24 18 5 E 28 15
Example 2: Select Columns in Range
The following code shows how to select columns in a range:
library(dplyr) #select columns in position 2 through 4 df %>% select(2:4) points assists rebounds 1 99 33 30 2 90 28 28 3 86 31 24 4 88 39 24 5 95 34 28
Example 3: Exclude Specific Columns
The following code shows how to exclude specific columns based on index position:
library(dplyr) #select all columns except those in position 1 and 2 df %>% select(-c(1, 2)) assists rebounds blocks 1 33 30 14 2 28 28 19 3 31 24 22 4 39 24 18 5 34 28 15
Notice that the first and second column are excluded.
Additional Resources
The following tutorials explain how to perform other common functions in dplyr:
How to Select Columns by Name Using dplyr
How to Filter Rows that Contain a Certain String Using dplyr
How to Select the First Row by Group Using dplyr
How to Replace NA with Zero in dplyr