Thanks. ave() is the exact function I was after.
tonyxv wrote: > > Hello, > I have a dataframe > > > ID1 ID2 > A1 B3 > A1 B4 > A1 B3 > A1 B3 > A2 B1 > A2 B1 > A2 B4 > A3 B2 > A3 B2 > A5 B1 > A5 B1 > A5 B6 > A5 B4 > A6 B2 > > > > I want to add extra columns to the dataframe CountID1 and CountID2 which > is the actual count of values such as A1 etc > ie > > > > ID1 ID2 CountID1 CountID2 > A1 B3 4 3 > A1 B4 4 4 > A1 B3 4 3 > A1 B3 4 3 > A2 B1 3 4 > A2 B1 3 4 > A2 B4 3 3 > A3 B2 2 3 > A3 B2 2 3 > A5 B1 4 4 > A5 B1 4 4 > A5 B6 4 1 > A5 B4 4 4 > A6 B2 1 3 > > > I know this can be done by first creating temporary aggregate dataframes > then merging with the original. > Is there an easier way if i want to calculate many aggregates without > having to merge many temp tables. > > > Thanks. > -- View this message in context: http://www.nabble.com/Adding-columns-of-Aggregates-to-existing-dataframe-tp18039838p18050190.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
