Constructing a zoo object is well covered in ?zoo and in the three vignettes:
vignette("zoo") vignette("zoo-quickref") vignette("zoo-faq") On Sat, Aug 2, 2008 at 10:27 AM, rcoder <[EMAIL PROTECTED]> wrote: > > Thanks for your reply Gabor. > > As I already have a dates column in my dataframe (in column row.names), is > it possible to preserve this whilst still making a data set suitable for > rollapply()? > > Thanks, > > rcoder > > > > Gabor Grothendieck wrote: >> >> If its regular you can convert it to ts or zoo. >> If its irregular convert it to zoo. There is no >> reason to expect rollapply to work with objects >> of other classes. Read ?ts and ?zoo. In >> ts note the start and frequency arguments. >> >> >> On Sat, Aug 2, 2008 at 7:50 AM, rcoder <[EMAIL PROTECTED]> wrote: >>> >>> Hi everyone, >>> >>> I have a data frame, with the following format: >>> >>> MatDate-> >>> row.names ID1 ID2 ID3 >>> 1 date1 >>> 2 date1 >>> 3 date3 >>> etc >>> >>> but I cannot perform a rollapply() statement on the matrix without >>> converting the matrix into a time series. >>> i.e. MatTs<-ts(MatDate) >> >> Use the start and frequency arguments. See ?ts >> >>> >>> Only then will my rollapply statement work: >>> MatMin<-rollapply(MatTs, 2,by=2, min, na.rm=F) >>> >>> If I apply the rollapply() statement to the dataframe, I get the >>> following >>> error: Error: could not find function "rollapply" >>> >>> The problem is that when I convert the data.frame matrix into a time >>> series >>> matrix, I lose the dates in the row.names column. I just want to know if >>> anyone could suggest a way to get around this problem, i.e. keep the >>> row.names column in place, and use the rollapply() statement as above. >>> >>> Thanks, >>> >>> rcoder >>> -- >>> View this message in context: >>> http://www.nabble.com/losing-row.names-in-matrix-operations-tp18788509p18788509.html >>> Sent from the R help mailing list archive at Nabble.com. >>> >>> ______________________________________________ >>> 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. >> >> > > -- > View this message in context: > http://www.nabble.com/losing-row.names-in-matrix-operations-tp18788509p18789688.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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.