Adding row to a data frame with missing values

Question

So I have this data frame

df <- data.frame( A=1:10, B=LETTERS[1:10], C=letters[1:10], stringsAsFactors= F )

I want to add a row to this

Answer 1

Here's an alternative base version that preserves the datatypes.

new.row <- head(df[NA,], 1)
new.row[c('A', 'B')] <- list(A=11, B='K')
rbind(df, new.row)