Depending on your situation you may want all=TRUE, all.x=TRUE, or all.y=TRUE. I think the SQL people call these outer joins, left outer joins, and right outer joins.
Bill Dunlap TIBCO Software wdunlap tibco.com On Thu, Jul 21, 2016 at 2:35 PM, lily li <chocol...@gmail.com> wrote: > I use this code, and it works. So has to set 'all=TRUE'. > > merge(df, data.frame(time=seq(as.Date("1990-01-01"), > to=as.Date("1990-12-31"), by="days")), all=TRUE) > > > On Thu, Jul 21, 2016 at 9:22 AM, Daniel Nordlund <djnordl...@gmail.com> > wrote: > > > On 7/20/2016 8:26 PM, lily li wrote: > > > >> Yes, I tried to create a dataframe and merge it with the shortened > >> dataframe. The resulting dataframe goes with the short one and truncates > >> the complete date column, so it does not work. > >> > >> On Wed, Jul 20, 2016 at 6:38 PM, David Winsemius < > dwinsem...@comcast.net> > >> wrote: > >> > >> > >>> On Jul 20, 2016, at 1:31 PM, lily li <chocol...@gmail.com> wrote: > >>>> > >>>> Hi R users, > >>>> > >>>> I have a dataframe, where there is a column 'time' represents time > >>>> series > >>>> but is not complete. How to expand the dataframe so this column will > >>>> > >>> become > >>> > >>>> complete, where other columns with the newly added rows have NA > values? > >>>> Thanks. > >>>> > >>>> df > >>>> A B C time > >>>> 10 5 3.3 1990-01-01 > >>>> 11 5 4 1990-02-07 > >>>> 12 4 3 1990-02-14 > >>>> ... > >>>> > >>> > >>> Make a dataframe with a 'time' column using seq.Date and merge that > >>> dataframe with your df dataframe. > >>> > >>> > >>>> [[alternative HTML version deleted]] > >>>> > >>> > >>> Really .... isn't it time you learned how to send plain text. You've > >>> posted many questions on Rhelp. It's really not that difficult on > >>> gmail. I > >>> also have a gmail account and have had no difficulty finding > instructions > >>> on how to do it. > >>> > >>> > >>>> ______________________________________________ > >>>> 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. > >>>> > >>> > >>> David Winsemius > >>> Alameda, CA, USA > >>> > >>> > >>> > >> > > Don't just say you tried to do the merge and it doesn't work. At a > > minimum show us the ACTUAL code you used and give us any error messages > you > > got or show us a portion of the results and explain why it is not what > you > > expected. If possible, give us a small amount of data using dput() so > that > > we can "play along at home" (i.e. give us a reproducible example). > > > > Dan > > > > Daniel Nordlund > > Port Townsend, WA > > > > > > > > -- > > Daniel Noredlund > > Bothell, WA USA > > > > > > ______________________________________________ > > 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. > > > > [[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. > [[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.