Why for loop only shows result of last loop

Question

I have this sample matrix:

  X1 X2 X3 X4
1  F  F  F  F
2  C  C  C  C
3  D  D  D  D
4 A# A# A#  A

And I\'m trying to use a for loop to get the n

Answer 1

You could use n_distinct (wrapper for length(unique() from dplyr

library(dplyr)
df1 %>%
   summarise_each(funs(n_distinct)) %>%
   unlist()