I think @ Flm is asking for some sample data from some of your existing data.frames.
Let's say you have three aata.frames, dat1, dat2, dat3.
We would like to see some sample data from each dataset. Something like the output from:
dput(head(dat1, 20)
dput(head(dat1, 20)
dput(head(dat1, 20)
In each case this should give us the first 20 rows of data form nte data.frame.
See ?dput for some information.
Then can you show us an example of how you would expect the new ID to look, perhaps explaining how you would get there?
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