Hi Phillip, While I really like Ana's solution, this might also help: phdf<-read.table(text="Date count 2018-03-29 1 2018-03-29 1 2018-03-29 1 2018-03-30 1 2018-03-30 1 2018-03-30 1 2018-03-31 1 2018-03-31 1 2018-03-31 1", header=TRUE,stringsAsFactors=FALSE) phdf$Date<-as.Date(phdf$Date,"%Y-%m-%d") incflag<-diff(phdf$Date)>0 phdf$count<-c(NA,cumsum(incflag)+1)
Jim On Sat, Sep 21, 2019 at 3:47 AM Phillip Heinrich <herd_...@cox.net> wrote: > > With the data snippet below I’m trying to increment the “count” vector by one > each time the date changes. > > Date count > 1 2018-03-29 1 > 2 2018-03-29 1 > 3 2018-03-29 1 > 81 2018-03-30 1 > 82 2018-03-30 1 > 83 2018-03-30 1 > 165 2018-03-31 1 > 166 2018-03-31 1 > 167 2018-03-31 1 > > > > > > > > I can get count to change when the date changes with the following code: > > test2 <- transform(test2, > + count = ifelse(Date == lag(Date,1),count,count+1)) > > test2 > Date count > 1 2018-03-29 NA > 2 2018-03-29 1 > 3 2018-03-29 1 > 81 2018-03-30 2 > 82 2018-03-30 1 > 83 2018-03-30 1 > 165 2018-03-31 2 > 166 2018-03-31 1 > 167 2018-03-31 1 > > > > > > > > ...but I want all three March 30 rows to have a count of 2 and the March 31 > rows to be equal to 3. Any suggestions? > > Thanks. > [[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.