CODEWITHSUNDEEP
rdataframe
LucasSeveryn
LucasSeveryn

Reputation: 6262

Remove row by row number in a dataframe

I would like to create a very simple function that will take the dataframe and row number as arguemnts, and then return a dataframe without that row. So if I have:

1 ben
2 adrian
3 bill
4 matthew

After calling remove(3,df) I will get:

1 ben
2 adrian
3 matthew

Anyone can help out?

Upvotes: 0

Views: 11168

Answers (3)

Rich Scriven
Rich Scriven

Reputation: 99331

It seems like this is all you really need

> removeRows <- function(rowNum, data) {
      newData <- data[-rowNum, , drop = FALSE]
      rownames(newData) <- NULL
      newData
  }
> dat
#        V2
# 1     ben
# 2  adrian
# 3    bill
# 4 matthew
> removeRows(3, dat)
#        V2
# 1     ben
# 2  adrian
# 3 matthew

Upvotes: 3

akrun
akrun

Reputation: 887128

If df is the dataset

fun1 <- function(data, rowN){
 indx <- !(seq_len(nrow(data)) %in% rowN)
 data1 <- data[indx,, drop=F]
 row.names(data1) <- seq_len(nrow(data1))
 data1
 }

fun1(df, 3)
#       V1
#1     ben
#2  adrian
#3 matthew

fun1(df,1:2)
#       V1
#1    bill
#2 matthew

Upvotes: 1

Dan
Dan

Reputation: 5369

This function can be written as a one-liner (albeit without error checking):

remrow <- function(x, rows) x[-rows,, drop = FALSE]

Here's your data:

dat <- data.frame(A = 1:4, B = 5:8)
rownames(dat) <- c("ben", "adrian", "bill", "matthew")

remrow(dat, 2) will strip out the "adrian" row, while remrow(dat, 1:2) will remove both the "ben" and "adrian" rows.

Note that is.data.frame(remrow(dat, 1)) evaluates to TRUE.

Upvotes: 4

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