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

You can just use sum(people$Weight).

sum sums up a vector, and people$Weight retrieves the weight column from your data frame.

Note - you can get built-in help by using ?sum, ?colSums, etc. (by the way, colSums will give you the sum for each column).