It seems row.names only shows up separately when it differs from the actual row numbers. I got them to go away by setting them as such, e.g. row.names(uniquedf) <- seq(nrow(uniquedf)) -- View this message in context: http://r.789695.n4.nabble.com/Remove-row-names-column-in-dataframe-tp856647p3574819.html Sent from the R help mailing list archive at Nabble.com.