Keep first occurrence of rows irrespective of column of each element

Question

Is there a function that treats the elements of a row as set and returns only the first occurrence of each unique set?

In example below, rows 1 and 3 should be considered equal. It should be irrelevant for the function foo whether an element is in col1 or col2.

df <- data.frame(col1 = c('a', 'b', '1'), col2 = c('1', '2', 'a'))


foo(df)

>   col1 col2
> 1    a    1
> 2    b    2

Have you tried unique(df) https://stackoverflow.com/questions/13843586/selecting-unique-rows-in-matrix-using-r — Corey Levinson, Jun 06 '18 at 17:07

score 1 · Accepted Answer · answered Jun 06 '18 at 17:10

1

You could do something like this..

df[!duplicated(t(apply(df,1,sort))),]

  col1 col2
1    a    1
2    b    2

It sorts each row (so that a-1 and 1-a end up the same), and then selects only those rows of df that are not duplicates.

answered Jun 06 '18 at 17:10

Andrew Gustar

1 Answers1