deleting all rows from column 1 with duplicates in column 2.

I have the following Table: Column 1 is the product ID and Column 2 is the previous product ID.

I want to delete all duplicates, so all values that are shown in colum 2 must be deleted from column 1. How can I do this.

Answer 1

[Matt J]

setdiff(Column1,Column2)

[Rafael Borobio Castillo]

Thanks it works quite well, at the end I finished using ismember to identificate the position of the duplicates because I need to eliminate this from a larger dataset.

All the best, Rafael