Hi Ahson, Guessing what your data frame might look like, here are two easy ways:
All_companies<-data.frame(year=c(1970:2015,2000:2015,2010:2015), COMPANY_NUMBER=c(rep(1,46),rep(2,16),rep(3,6)), COMPANY_NAME=c(rep("IBM",46),rep("AMAZON",16),rep("SPACE-X",6))) # easy ways table(All_companies$COMPANY_NAME) table(All_companies$COMPANY_NUMBER) I'm too lazy to provide a difficult way. Jim On Wed, Jul 22, 2020 at 3:21 AM e-mail ma015k3113 via R-help <r-help@r-project.org> wrote: > > Dear All, I have a dataframe which has a few thousand companies with unique > company numbers and names and each company has data for several years and > each year is stored in a separate row. > > I want to get a total for the number of years of data for each company. When > I loop through the data with the following command I get a value of ‘1’ > rather than a total of the rows for each company > > All_companies$count <-0 > > while All_companies$COMPANY_NAME == All_companies$COMPANY_NAME + 1 > > + {All_companies$count=All_companies$count+1} > > Can you kindly help me on this? > > Ahson > [[alternative HTML version deleted]] > > ______________________________________________ > 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.