Drop Columns of R DataFrame
In this tutorial, we will learn how to delete or drop a column or multiple columns from a dataframe in R programming with examples.
You cannot actually delete a column, but you can access a dataframe without some columns specified by negative index. This is also called subsetting in R programming.
To delete a column, provide the column number as index to the Dataframe. The syntax is shown below:
mydataframe[-c(column_index_1, column_index_2)]
where
mydataframe
is the dataframe.column_index_1, column_index_2, . . .
are the comma separated indices which should be removed in the resulting dataframe.
Example 1 – Drop Column from Dataframe
Let us create a dataframe, DF1
> DF1 = data.frame(V1= c(1, 5, 14, 23, 54), V2= c(9, 15, 85, 3, 42), V3= c(9, 7, 42, 87, 16)) > DF1 V1 V2 V3 1 1 9 9 2 5 15 7 3 14 85 42 4 23 3 87 5 54 42 16 >
Let us assume that we need DF1
with V2
column deleted. The index of V2
column is 2. Now, we will access this dataframe with a negative index and store the result in another Dataframe DF2
.
> DF2 = DF1[-2] > DF2 V1 V3 1 1 9 2 5 7 3 14 42 4 23 87 5 54 16 >
Viola. We have created a new dataframe with a column deleted from the previous dataframe.
Example 2 – Delete Multiple Columns from DataFrame
Let us create a dataframe, DF1
> DF1 = data.frame(V1= c(1, 5, 14, 23, 54), V2= c(9, 15, 85, 3, 42), V3= c(9, 7, 42, 87, 16), V4= c(17, 25, 14, 23, 54), V5= c(9, 15, 85, 43, 2), V6= c(9, 75, 4, 7, 6)) > DF1 V1 V2 V3 V4 V5 V6 1 1 9 9 17 9 9 2 5 15 7 25 15 75 3 14 85 42 14 85 4 4 23 3 87 23 43 7 5 54 42 16 54 2 6 >
Let us assume that we need DF1
with V2
and V3
deleted. The index of V2
is 2 and V3
is 3. Now, we will access this dataframe with a vector of negative indices and store the result in another Dataframe DF2
.
> DF2 = DF1[c(-2,-3)] > DF2 V1 V4 V5 V6 1 1 17 9 9 2 5 25 15 75 3 14 14 85 4 4 23 23 43 7 5 54 54 2 6 >
Viola. We have created a new dataframe with multiple columns deleted from the previous dataframe.
Conclusion
In this R Tutorial, we have learnt how to delete or drop a column or multiple columns from an R DataFrame.