Hi I am not an expert in time series. The problem is that resulting list is not time series any more. So you need to convert it again to time series and you need to give it frequency greater than 1.
something like l.blist <- lapply(blist, function (x) HoltWinters(ts(x, frequency=2))) But this depends on how your data are structured after splitting them to months. Regards Petr From: Antonio Silva [mailto:aolinto....@gmail.com] Sent: Tuesday, December 04, 2012 11:50 AM To: PIKAL Petr Cc: R-help@r-project.org Subject: Re: [R] partial analisys of a time series Thanks Petr I thought there might be an equivalent for birthstimeseries[,1] if it were a dataframe, but split function sounds great. I could not reproduce the second line of your suggestion "l.blist <- lapply(blist, HoltWinters)". I receive the message: Error in decompose(ts(x[1L:wind], start = start(x), frequency = f), seasonal) : time series has no or less than 2 periods What could be going wrong? Best regards Antonio 2012/12/4 PIKAL Petr <petr.pi...@precheza.cz<mailto:petr.pi...@precheza.cz>> Hi > -----Original Message----- > From: r-help-boun...@r-project.org<mailto:r-help-boun...@r-project.org> > [mailto:r-help-bounces@r-<mailto:r-help-bounces@r-> > project.org<http://project.org>] On Behalf Of Antonio Silva > Sent: Tuesday, December 04, 2012 10:26 AM > To: R-help@r-project.org<mailto:R-help@r-project.org> > Subject: [R] partial analisys of a time series > > Dear list members > > I want to analyze separately the months of a time series. In other > words, I want to plot and fit models for each month separately. > > Taking the example of > http://a-little-book-of-r-for-time- > series.readthedocs.org/en/latest/src/timeseries.html<http://series.readthedocs.org/en/latest/src/timeseries.html> > > births <- scan("http://robjhyndman.com/tsdldata/data/nybirths.dat";) > birthstimeseries <- ts(births, frequency=12, start=c(1946,1)) > birthstimeseries > plot.ts(birthstimeseries) > birthstimeseriesHW <- HoltWinters(birthstimeseries) > plot(birthstimeseriesHW) > > How to proceed the plotting and HoltWinters smoothing considereing only > Januarys, Februarys, etc. separately. Split your data by months to a list, use lapply. using zoo package blist <-split(birthstimeseries, months(as.Date(birthstimeseries))) l.blist <- lapply(blist, HoltWinters) Regards Petr > > Thanks in advance. > > Antonio Olinto > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org<mailto: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. -- Antônio Olinto Ávila da Silva Biólogo / Oceanógrafo Instituto de Pesca (Fisheries Institute) São Paulo, Brasil [[alternative HTML version deleted]]
______________________________________________ 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.
