Remove same columns from left_join

Question

I\'d like to merge two data frames by id, but they both have 2 of the same columns; therefore, when I merge i get new .x and .y column

Answer 1

After having checked that these columns are indeed the same, you could just remove them before doing the join

if (all(df1[,c('element', 'day')] == df2[,c('element', 'day')]))
  df <- left_join(df1[,setdiff(colnames(df1),c('element', 'day'))], df2, by = "id")
else
  stop("Should not happen!?")