Looks like a job for aggregate() -pd
On 13 Oct 2014, at 04:25 , dila radi <dilarad...@gmail.com> wrote: > Hi all, > > Could someone help me on this? I have this kind of data set > > structure(list(Year = c(1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, 1972L, > 1972L, 1972L, 1972L, 1972L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, 1973L, > 1973L, 1973L, 1973L, 1973L), Month = c(1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 2L, 2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, > 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, > 3L, 3L, 3L, 3L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, > 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, > 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L, > 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, > 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L), Rain = c(68, 6, 6.3, 55.3, > 18.2, 1.2, 5.3, 0, 0, 1.2, 0.2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2.5, > 0, 0, 12.1, 0.5, 0, 0, 0, 0, 0, 0, 0.5, 0, 0, 0, 0, 0, 0, 0, > 0, 0, 0, 0, 0, 0, 50.8, 7.1, 0, 0, 0, 4, 22, 14.7, 0, 17.7, 0, > 106.6, 0, 4.8, 14.7, 2.2, 0, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, > 0, 8.6, 3.3, 0, 16.7, 0, 5.8, 9.1, 0, 0, 0, 0, 0, 0, 0, 12.6, > 12.9, 0, 0, 0, 0, 0, 3.3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 50.7, > 1.2, 2.5, 0, 0, 0, 0, 17, 0, 2.5, 0, 0, 0, 0, 3.8, 0, 0, 0, 0, > 0, 0, 2.7, 2.7, 12.6, 0, 0, 0, 0, 0, 0, 0, 3.3, 0, 0, 5.5, 2.5, > 0, 35.5, 5, 3.3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6.3, > 0, 0, 0, 5.8, 0, 0, 0, 15.4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5.5, > 30.2, 64.5, 0, 11.9, 3.8, 3.3, 7.1, 27.9, 32, 106.6, 0.2, 0, > 5.3, 4.5, 0, 0, 1.5, 11.9, 6.6, 0, 0, 11.9, 0, 0, 0, 0, 0, 0, > 0, 0, 0, 0, 8.3, 8.1, 0.5, 0, 0, 0, 0, 0, 0, 0, 0, 30.9, 1.2, > 0, 0, 9.3, 82.5, 16.5, 0, 0, 0, 0.7, 0, 0, 36, 0, 3.8, 0, 0, > 0, 0, 0, 0, 0, 4.3, 0, 0, 38, 8.8, 0, 26.4, 0, 0, 0.7, 13.4, > 9.6, 8.3, 0, 3.8, 8.8, 0, 45.7, 1.2, 12.9, 0, 0, 0, 21.3, 1, > 0)), .Names = c("Year", "Month", "Rain"), class = "data.frame", row.names = > c(NA, > -271L)) > > and I want to find the sum of Rain in column 3 according to their month. > How could I achieved this so that it would appear as follow: > > structure(list(Year = c(1971L, 1971L, 1971L, 1972L, 1972L, 1972L, > 1973L, 1973L, 1973L), Month = c(1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, > 3L), Rain = c(176.8, 228.2, 90.9, 81, 73.1, 127.7, 242.8, 189.5, > 204.2)), .Names = c("Year", "Month", "Rain"), class = "data.frame", > row.names = c(NA, > -9L)) > > Thank you so much > > Dila > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ 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.