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How to get list of all columns except one or more columns from an R data frame?


Sometimes, we want to use some columns of an R data frame for analysis, therefore, it is better to get a list of all the columns that we need. In this way, we don't have to worry about the column operations, if required because we will be having only necessary columns. To get the list of all columns except one or more columns can be done with the help of single square brackets.

Example

Consider the below data frame −

set.seed(100) x1 <-LETTERS[1:20] x2 <-sample(1:100,20) x3 <-sample(1:10,20,replace=TRUE) x4 <-rnorm(20) df <-data.frame(x1,x2,x3,x4) df

Output

   x1  x2  x3  x4 1 A 74 2 -0.69001432 2 B 89 3 -0.22179423 3 C 78 4 0.18290768 4 D 23 4 0.41732329 5 E 86 4 1.06540233 6 F 70 5 0.97020202 7 G 4 7 -0.10162924 8 H 55 9 1.40320349 9 I 95 4 -1.77677563 10 J 7 2 0.62286739 11 K 91 6 -0.52228335 12 L 93 7 1.32223096 13 M 43 1 -0.36344033 14 N 82 6 1.31906574 15 O 61 9 0.04377907 16 P 12 9 -1.87865588 17 Q 51 9 -0.44706218 18 R 72 6 -1.73859795 19 S 18 8 0.17886485 20 T 25 7 1.89746570

Example

df[,1] [1] A B C D E F G H I J K L M N O P Q R S T Levels: A B C D E F G H I J K L M N O P Q R S T df[,1:3]

Output

x1 x2 x3 1 A 74 2 2 B 89 3 3 C 78 4 4 D 23 4 5 E 86 4 6 F 70 5 7 G 4 7 8 H 55 9 9 I 95 4 10 J 7 2 11 K 91 6 12 L 93 7 13 M 43 1 14 N 82 6 15 O 61 9 16 P 12 9 17 Q 51 9 18 R 72 6 19 S 18 8 20 T 25 7

Example

df[,c(2,4)]

Output

df[,c(2,4)]

Example

   x2    x4 1 74 -0.69001432 2 89 -0.22179423 3 78 0.18290768 4 23 0.41732329 5 86 1.06540233 6 70 0.97020202 7 4 -0.10162924 8 55 1.40320349 9 95 -1.77677563 10 7 0.62286739 11 91 -0.52228335 12 93 1.32223096 13 43 -0.36344033 14 82 1.31906574 15 61 0.04377907 16 12 -1.87865588 17 51 -0.44706218 18 72 -1.73859795 19 18 0.17886485 20 25 1.89746570

Example

df[,-c(2,4)]

Output

x1 x3 1 A 2 2 B 3 3 C 4 4 D 4 5 E 4 6 F 5 7 G 7 8 H 9 9 I 4 10 J 2 11 K 6 12 L 7 13 M 1 14 N 6 15 O 9 16 P 9 17 Q 9 18 R 6 19 S 8 20 T 7

Example

df[,-1]

Output

x2    x3    x4 1 74 2 -0.69001432 2 89 3 -0.22179423 3 78 4 0.18290768 4 23 4 0.41732329 5 86 4 1.06540233 6 70 5 0.97020202 7 4 7 -0.10162924 8 55 9 1.40320349 9 95 4 -1.77677563 10 7 2 0.62286739 11 91 6 -0.52228335 12 93 7 1.32223096 13 43 1 -0.36344033 14 82 6 1.31906574 15 61 9 0.04377907 16 12 9 -1.87865588 17 51 9 -0.44706218 18 72 6 -1.73859795 19 18 8 0.17886485 20 25 7 1.89746570

Example

df[,-4]

Output

x1 x2 x3 1 A 74 2 2 B 89 3 3 C 78 4 4 D 23 4 5 E 86 4 6 F 70 5 7 G 4 7 8 H 55 9 9 I 95 4 10 J 7 2 11 K 91 6 12 L 93 7 13 M 43 1 14 N 82 6 15 O 61 9 16 P 12 9 17 Q 51 9 18 R 72 6 19 S 18 8 20 T 25 7

raja

Published on 21-Aug-2020 11:42:53

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Source: https://www.tutorialspoint.com/how-to-get-list-of-all-columns-except-one-or-more-columns-from-an-r-data-frame

Posted by: blackcurrent05.blogspot.com