How to get the maximum value by group

Question

I have a data.frame with two columns: year and score. The years go from 2000-2012 and each year can be listed multiple times. In the s

Answer 1

If you know sql this is easier to understand

library(sqldf)
sqldf('select year, max(score) from mydata group by year')

Update (2016-01): Now you can also use dplyr

library(dplyr)
mydata %>% group_by(year) %>% summarise(max = max(score))