Choose Specific Columns of a Data Frame in R Programming – select() Function
Last Updated :
19 Jun, 2020
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select() function in R Language is used to choose whether a column of the data frame is selected or not.
Syntax: select(x, expr)
Parameters:
x: Data frame
expr: condition for selection
Example 1:
# R program to select specific columns # Loading library library(dplyr) # Create a data frame d <- data.frame( name = c("Abhi", "Bhavesh", "Chaman", "Dimri"), age = c(7, 5, 9, 16), ht = c(46, NA, NA, 69), school = c("yes", "yes", "no", "no") ) # startswith() function to print only ht data select(d, starts_with("ht")) # -startswith() function to # print everything except ht data select(d, -starts_with("ht")) |
Output:
ht
1 46
2 NA
3 NA
4 69
name age school
1 Abhi 7 yes
2 Bhavesh 5 yes
3 Chaman 9 no
4 Dimri 16 no
Example 2:
# R program to select specific columns # Loading library library(dplyr) # Create a data frame d <- data.frame( name = c("Abhi", "Bhavesh", "Chaman", "Dimri"), age = c(7, 5, 9, 16), ht = c(46, NA, NA, 69), school = c("yes", "yes", "no", "no") ) # Printing column 1 to 2 select(d, 1:2) # Printing data of column heading containing 'a' select(d, contains("a")) # Printing data of column heading which matches 'na' select(d, matches("na")) |
Output:
name age
1 Abhi 7
2 Bhavesh 5
3 Chaman 9
4 Dimri 16
name age
1 Abhi 7
2 Bhavesh 5
3 Chaman 9
4 Dimri 16
name
1 Abhi
2 Bhavesh
3 Chaman
4 Dimri
