In your sample data.frame, MyDate and MyDes are factors; is that what you want? rs
On Samstag, 16. März 2019 01:40:01 CET Ek Esawi wrote: > Hi All— > > I have a data frame with over 13000 rows and 4 columns. A mini data > frame is given at the bottom. I want to split the data frame into > lists each corresponds to single year which ranges from 1990 to 2018). > I wanted to use the split function, but it requires a vector of the > same length as MyDate which contains many multiples of each year. > Any help is highly appreciated. > > I want the following results: > List 1990 > MyDate MyNo MyDes > 1990 > 1990 > 1990 > …... > List 2000 > 2000 > 2000 > 2000 > …... > List 2001 > 2001 > 2001 > 2001 > 2001 > …... > List 2018 > 2018 > 2018 > 2018 > …... > > Sample data frame > > mydf <- > data.frame(MyDate=c("1990-01-01","1990-04-07","2000-04-05","2018-01-04"),MyNo=c(1,2,3,4),MyDes=c("AA","BB","CC","DD")) > > > EK > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. > ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.