How to delete the first row of a dataframe in R?

Question

I have a dataset with 11 columns with over 1000 rows each. The columns were labeled V1, V2, V11, etc. I replaced the names with something more useful to me using the "c" command. I didn't realize that row 1 also contained labels for each column and my actual data starts on row 2.

Is there a way to delete row 1 and decrement?

Answer 1

To delete the first row of a data frame, you can use the negative indices as follows:

data_frame = data_frame[-1,]

To keep labels from your original file, do the following:

data_frame = read.table('data.txt', header = T)

To delete a column:

data_frame$column_name = NULL

For example:

 x = rnorm(10)

 y = runif(10)

df = data.frame( x, y )

df

             x          y

1  -1.74553874 0.24904310

2   0.78970091 0.40401348

3   0.86203201 0.50361443

4  -0.02194766 0.19179475

5   1.07919386 0.70638636

6  -0.23485948 0.41544163

7   0.07170211 0.08740739

8  -2.18997110 0.63813427

9   0.68096662 0.59799302

10  0.05319090 0.13227670

df[-1,] #delete 1st row

             x          y

2   0.78970091 0.40401348

3   0.86203201 0.50361443

4  -0.02194766 0.19179475

5   1.07919386 0.70638636

6  -0.23485948 0.41544163

7   0.07170211 0.08740739

8  -2.18997110 0.63813427

9   0.68096662 0.59799302

10  0.05319090 0.13227670

df$y <- NULL   #delete column “y”

df

             x

1  -1.74553874

2   0.78970091

3   0.86203201

4  -0.02194766

5   1.07919386

6  -0.23485948

7   0.07170211

8  -2.18997110

9   0.68096662

10  0.05319090

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Answer 2

Below are methods to delete first row of data frame in r:
 

• Method 1: Using Negative Indexing
  You can exclude the first row by using negative indexing:
  sample code:
  df <- data.frame(
  A = c(1, 2, 3),
  B = c("a", "b", "c")
  )
  
  # Delete the first row
  df <- df[-1, ]

• Method 2: Using slice() from dplyr
  If you prefer using the dplyr package, you can use the slice() function:
  sample code:
  library(dplyr)
  
  df <- data.frame(
  A = c(1, 2, 3),
  B = c("a", "b", "c")
  )
  
  # Delete the first row
  df <- df %>% slice(-1)
  
   

• Method 3: Using head()
  Another way is to use the head() function to keep all rows except the first:
  sample code:
  df <- data.frame(
  A = c(1, 2, 3),
  B = c("a", "b", "c")
  )
  
  # Delete the first row
  df <- head(df, -1)
   

Any of these methods will effectively remove the first row of your dataframe. After executing the code, the variable df will contain the modified dataframe without the first row.