Using dplyr summarize with different operations for multiple columns

Question

Well, I know that there are already tons of related questions, but none gave an answer to my particular need.

I want to use dplyr \"summarize\" on a table with 50 co

Answer 1

You could summarise the data with each function separately and then join the data later if needed.

So something like this for the iris example:

sums <- iris %>% group_by(Species) %>% summarise_at(1:2, sum)
means <- iris %>% group_by(Species) %>% summarise_at(3, mean)
firsts <- iris %>% group_by(Species) %>% summarise_at(4, first)
full_join(sums, means) %>% full_join(firsts)

Though I would try to think of something else if there are more than a handful of summarising functions you need to use.