Summing up a col and storing the value at the last index in a new column in R

Question

Suppose I have a dataframe

How do I get the following in R

      col1   col2
df=    1      
       2
       3
       4      10(total of col1)

@Ronak Shah. It does'nt not answer my question – Saideep Jul 16 '20 at 01:01 — Saideep, Jul 16 '20 at 01:01
Did you check my below answer, did it work for you? – Ronak Shah Jul 17 '20 at 06:59 — Ronak Shah, Jul 17 '20 at 06:59

score 0 · Answer 1 · answered Jul 16 '20 at 01:07

You can do :

df <- data.frame(col1 = 1:4)
df$col2 <- NA
df$col2[nrow(df)] <- sum(df$col1, na.rm = TRUE)
df
#  col1 col2
#1    1   NA
#2    2   NA
#3    3   NA
#4    4   10

Keeping other values in col2 as NA instead of blanks since blanks would turn the column to character.

Summing up a col and storing the value at the last index in a new column in R

1 Answers1