R - find and calculate with unique combinations of values
- by lecodesportif
I would like to work with unique combinations of var1 and var2.
foo <- data.frame(var1= c(1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4), var2=c(1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 2, 3, 3))
As has been noted (+1 for answers), unique(foo) results in this:
var1 var2
1 1 1
2 2 1
3 2 2
4 3 1
5 3 2
6 4 2
7 4 3
Based on the unique combinations, how do I get the number of occurrences of a var1 value and the sum (bla) of each var1 value's var2 values. The output could look like this:
var1 n bla
1 1 1 1
2 2 2 3
3 3 2 3
4 4 2 5
edit: The question was too basic and probably duplicate so I extended it.