See ?cut.Date In the zoo package see: ?as.yearmon ?as.yearqtr ?aggregate.zoo
and the many examples in: ?plot.zoo ?xyplot.zoo as well as the three zoo vignettes. Also in the xts package look at ?to.period For regularly spaced series the tis package supports a wide variety of time bases and can convert among them. There are as.zoo.tis and as.tis.zoo routines in zoo and tis; also, xts is a subclass of zoo so all these packages can work together. On Thu, Sep 11, 2008 at 11:02 AM, hadley wickham <[EMAIL PROTECTED]> wrote: > Dear all, > > I've been struggling to perform common operations on dates that I need > to be able to correct draw date-time scales - in particular I need to > be able to round/truncate/ceiling dates to arbitrary precision - e.g. > to weeks, months or years (or multiples thereof). I haven't been able > to find anything to do this in base R (trunc.Date only truncates to > sub-day units), or in the date related contributed packages I've > looked in (e.g. chron). Have I missed something? > > Otherwise, I have been working on a bottom up set of functions to make > date manipulation easier - http://gist.github.com/10238. These should > work for all date-time types and I've tried to use a consistent naming > scheme and consistent output conventions. This seems like a rather > small bundle of functions to be worth turning into a package, so I was > wondering if anyone would be interested in adopting them into an > existing date-time related package. > > Regards, > > Hadley > > -- > http://had.co.nz/ > > ______________________________________________ > 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. > ______________________________________________ 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.