Here is head of my dataset as follows:
ID L.NO Root1 Root2 Root3
1 2120 SX NA NA
2 2121 NC NA NA
3 2122 NA NA SX
4 2223 NA CX PX
5 2224 NA SX LX
I'd like to count non-null variables and put into a new column by grouping ID. How can I do that in R?
ID L.NO Root1 Root2 Root3 NewCol
1 2120 SX NA NA 2
2 2121 NC NA NA 2
3 2122 NA NA SX 2
4 2223 NA CX PX 1
5 2224 NA SX LX 1