Table of Contents
In R, there are two main ways to remove the first row of a data frame. The first is to use the ‘subset’ function, which allows the user to select specific rows from the data frame. The second method is to use the ‘head’ function, which allows the user to specify the number of rows to be removed from the beginning of the data frame. Both methods are easy to use and can quickly remove the first row from a data frame.
You can use one of the following methods to remove the first row from a data frame in R:
Method 1: Use Base R
df <- df[-1, ]
Method 2: Use dplyr package
library(dplyr)
df <- df %>% slice(-1)
The following examples show how to use each method in practice.
Example 1: Remove First Row Using Base R
Suppose we have the following data frame in R:
#create data frame
df <- data.frame(team=c(NA, 'A', 'B', 'C', 'D', 'E'),
points=c(NA, 99, 90, 86, 88, 95),
assists=c(NA, 33, 28, 31, 39, 34),
rebounds=c(NA, 30, 28, 24, 24, 28))
#view data frame
df
team points assists rebounds
1 <NA> NA NA NA
2 A 99 33 30
3 B 90 28 28
4 C 86 31 24
5 D 88 39 24
6 E 95 34 28
We can use the following code to remove the first row from the data frame:
#remove first row
df <- df[-1, ]
#view updated data frame
df
team points assists rebounds
2 A 99 33 30
3 B 90 28 28
4 C 86 31 24
5 D 88 39 24
6 E 95 34 28
Notice that the first row has been removed.
Also notice that the row names now start at 2.
To reset the row names to start at 1, simply use the following code:
#reset row names
rownames(df) <- NULL
#view updated data frame
df
team points assists rebounds
1 A 99 33 30
2 B 90 28 28
3 C 86 31 24
4 D 88 39 24
5 E 95 34 28
Example 2: Remove First Row Using dplyr Package
Suppose we have the following data frame in R:
#create data frame
df <- data.frame(team=c(NA, 'A', 'B', 'C', 'D', 'E'),
points=c(NA, 99, 90, 86, 88, 95),
assists=c(NA, 33, 28, 31, 39, 34),
rebounds=c(NA, 30, 28, 24, 24, 28))
#view data frame
df
team points assists rebounds
1 <NA> NA NA NA
2 A 99 33 30
3 B 90 28 28
4 C 86 31 24
5 D 88 39 24
6 E 95 34 28
We can use the function from the dplyr package to remove the first row from the data frame:
library(dplyr)
#remove first row from data frame
df <- df %>% slice(-1)
#view updated data frame
df
team points assists rebounds
1 A 99 33 30
2 B 90 28 28
3 C 86 31 24
4 D 88 39 24
5 E 95 34 28
Notice that the first row has been removed.
The nice thing about using this approach is that the row numbers are automatically reset after removing the first row.
The following tutorials explain how to perform other common tasks in R: