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Get List of All Columns Except Specified Columns from 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
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