How to sum data.frame column values?

Question

I have a data frame with several columns; some numeric and some character. How to compute the sum of a specific column? I’ve googled for this and I see nume

Answer 1

to order after the colsum :

order(colSums(people),decreasing=TRUE)

if more than 20+ columns

order(colSums(people[,c(5:25)],decreasing=TRUE) ##in case of keeping the first 4 columns remaining.