On Mar 6, 2013, at 3:21 PM, Francisco Carvalho Diniz wrote: > Hi, > > I have a data frame with two columns. I need to remove duplicated rows in > first column, but I need to do it conditionally to values of the second > column. > > Example: > > Point_counts Psi_Sp > > 1 A 0 > 2 A 1 > 3 B 1 > 4 B 2 > 5 B 0 > 6 C 1 > 7 D 1 > 8 D 2 > > > I need to turn this data frame in one without duplicated rows at > point-counts (one visit per point) but maintain the ones with maximum value > at Psi_Sp, e.g. remove row 1 and maintain 2 or remove rows 3 and 5 and > maintain 4. At the end I want a data frame like the one below: > Try this:
dfrm <- dfrm[ order(dfrm[[1]], -dfrm[[2]] ) , ] #put desired rows at top of each Point_counts category # then take top item in each category dfrm[ !duplicated(dfrm[[1]]) , ] > Point_counts Psi_Sp > > 1 A 1 > 2 B 2 > 3 C 0 > 4 D 2 > > How can I do it? I found several ways to edit data frames, but > unfortunately I cound not use none of them. > > I appreciate > -- David Winsemius Alameda, CA, USA ______________________________________________ R-help@r-project.org 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.
