I have a data frame called df that looks like this:
df
name score1 score2 score3 Joe 1 NA 3 Jane NA 2 3
How do I make a column named sum that sums non-empty cells in score1, score2 and score3?
sum
score1
score2
score3
df$sum <- rowSums(df[,2:4], na.rm = TRUE)