I am starting to learn R, I apologize for my basic question.
I need to match two data frames. Basically, I need to replicate what in excel I do through vertical lookup. I have the same codes in the two data frames with these characteristics:
Dataframe 1. The common codes (with Dataframe 2) may be repeated several times along a column in Data frame 1, over different months. The column also includes codes that are not present in Dataframe 2.
Dataframe 2. The DF contains a shorter column than Dataframe 1, with only some codes (in common).
I need to create a Dataframe 1BIS, which has one more column than DF1, which indicates if the codes that are in data frame 1 are also present in the data frame 2 or not.
Any suggestions would be really appreciated. Let me know if I should provide further detail.
