Selecting top N rows for each group based on value in column

Question

I have dataframe like below :-

x<-c(3,2,1,8,7,11,10,9,7,5,4)
y<-c(\"a\",\"a\",\"a\", \"b\",\"b\",\"c\",\"c\",\"c\",\"c\",\"c\",\"c\")
z<-c(2,2,2,1,1         


        

Answer 1

I'm posting the solution I was looking for using dplyr. It is based on @HNSKD:

library(dplyr)
x<-c(3,2,1,8,7,11,10,9,7,5,4)
y<-c("a","a","a", "b","b","c","c","c","c","c","c")
z<-c(2,2,2,1,1,3,3,3,3,3,3)

df<-data.frame(x,y,z)

df %>% group_by(y) %>% slice(1:2)

Which returns the first two elements for each y:

# A tibble: 6 x 3
# Groups:   y [3]
      x y         z
    
1     3 a         2
2     2 a         2
3     8 b         1
4     7 b         1
5    11 c         3
6    10 c         3