Hello Can someone explain me the difference between aggregate and merge, please? I've read the help on both commands but I don't understant the difference. thanks -- View this message in context: http://r.789695.n4.nabble.com/aggregate-vs-merge-tp2255300p2255300.html Sent from the R help mailing list archive at Nabble.com.
On Jun 14, 2010, at 10:06 PM, skan wrote:> > Hello > > Can someone explain me the difference between aggregate and merge, > please? > I've read the help on both commands but I don't understant the > difference. >Merge adds data from one dataframe to another based on a matching process. Aggregate, which is a wrapper for tapply, works within one dataframe to apply a chosen function to "like" rows. -- David.