Fill missing combinations in a dataframe

Question

My example dataset:

df <- data.frame(
 REGION = c(\"REGION A\", \"REGION A\", \"REGION B\"), 
 CATEGORY = c(\"A\", \"B\", \"B\"), 
 VALUE1 = c(2,3,4),
 VA         


        

Answer 1

Using complete from tidyr:

library(tidyr)
as.data.frame(complete(df,REGION,CATEGORY,fill=list(VALUE1=0,VALUE2=0)))

Output:

    REGION CATEGORY VALUE1 VALUE2
1 REGION A        A      2      1
2 REGION A        B      3      2
3 REGION B        A      0      0
4 REGION B        B      4      3

If there are many variables, you could also just do as.data.frame(complete(df,REGION,CATEGORY)) and replace the NA's afterwards.

Hope this helps!