So I got these two data frames:
a <- c('A','B','C')
frame1 <- data.frame(a)
a <- c('A','A','B','B','C','C','C')
b <- c(12,18,120,9,1,7,12)
frame2<- data.frame(a,b)
Now I would like to know how many times each unique value in column 'a' occurs in frame2 and add this value to frame1.
The result should look like this:
a c
1 A 2
2 B 2
3 C 3
