I have a quick question regarding the R data.frame. My data.frame looks like this:
Category    Money
A            4
B            2
B            9
A            3
C            6         
A            2
C            4
B            8
My goal is to order this data frame such that every Category has the added up amount of money in their corresponding row. Like:
Category Money
A            9
B            19
C            10
I would really appreciate your help.
