[Solved] how to unique a data frame by the values in a specified column?

Question

I created a sample data. Hope this is what you need

df <- data.frame(names=c('A','A','A','A','B','B','B','C','C','C','C','C'),Length=c(1:12))

library(plyr)
 df2<- ddply(df, "names", subset, Length==max(Length))

Accepted Answer

I created a sample data. Hope this is what you need

df <- data.frame(names=c('A','A','A','A','B','B','B','C','C','C','C','C'),Length=c(1:12))

library(plyr)
 df2<- ddply(df, "names", subset, Length==max(Length))