Hi,
If I have two datasets like this:
df=data.frame("id"=rep(1:10,10, each=10), "item1"=sample(1:20, 100, replace=T)
df2=data.frame("a"=c(8, 8,10,9, 5, 1,2,1), "b"=c(16,18,11, 19,18, 11,17,12))
How do I find out which ids in the df dataset that has a match for both the
numbers occuring in the same row in the df2 dataframe? In the output I would
like to get the matching id and the rownumber from the df2.
Output something like this
Id Rownr
2 1
5 1
7 4
My actual problem is more complex with even more columns to be matched and the
datasets are large, hence the solution needs to be efficient.
Kind regards,
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