How to sum a variable by group in R
I have a data frame of consisting two columns"Players" & "points"x<-data.frame(Players=c("Player1","Player2","Player3","Player2","Player3","Player1"),points=c(10,20,30,13,17,18))
Players points
1 Player1 10
2 Player2 20
3 Player3 30
4 Player2 13
5 Player3 17
6 Player1 18
I want to sort the data by players and sum the points:
Like this:
Players x
1 Player1 28
2 Player2 33
3 Player3 47
To sum by group in r, you can use the group_by and the summarise_at functions to get the summation by group: iris %>% # Specify data frame group_by(Species) %>% # Specify group indicator summarise_at(vars(Sepal. Length), # Specify column list(name = sum)) # Specify function # A tibble: 3 x 2 # Species name # # 1 setosa 250.