How to create a sum if multiple criteria

Question

I have to create a "sum if" by column with multiple criteria.

I've tried this:

b <- DB.all %>% group_by(Family) %>% summarise(x)

But it doesn't work.

How can I do it?

It's not easy to understand what you want to do, could you provide an example? You should read this:[How to make a great R reproducible example](http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example/5963610#5963610) — Scarabee, Oct 30 '16 at 19:28
do you possibly want `DB.all %>% group_by(Family) %>% summarise_all(sum)` ... ? — Ben Bolker, Oct 30 '16 at 22:50
If you want to take a sum, then you need to use the `sum` function somewhere... — Gregor Thomas, Oct 30 '16 at 22:53

score 1 · Accepted Answer · answered Oct 30 '16 at 19:12

1

Try this:

library(dplyr)
b <- DB.all %>% group_by(Family) %>% summarise(sum(x))

answered Oct 30 '16 at 19:12

Scarabee

1 Answers1