How to concatenate multiple columns in one and remove duplicates?

January 7, 2022

I have a dataframe like this one:

A <- c("a", "a", "a", "a")
B <- c("b", "b", "b", "b")
C <- c("c", "a", "c", "c")
D <- c("d", "b", "a", "d")
E <- c("a", "a", "b", "e")
F <- c("b", "b", "c", "f")
G <- c("c", "a", "a", "g")
df <- data.frame(A, B, C, D, E, F, G)

I need to merge all values from the columns A to G, remove duplicates, and store a resulting list in a new column. So, the final result should look like this:

>Solution :

Try this one

> df$new <- apply(df,1,unique)
> df
  A B C D E F G                 new
1 a b c d a b c          a, b, c, d
2 a b a b a b a                a, b
3 a b c a b c a             a, b, c
4 a b c d e f g a, b, c, d, e, f, g