ts() only knows about monthly and quarterly series, not biannual ones.
You need to look into methods for irregular series (zoo, its, tseries
...), or add dates yourself (?plot.POSIXct). E.g.
> x<-sample (10:100, 17)
> x<-ts(x, start=c(1998,1), frequency=2)
> xtime <- seq(as.Date("1998-05-01"), by="6 months",
length=17)
> plot(xtime, x, xaxt="n")
> axis.Date(1, xtime, xtime)
You'll have trouble fitting the dates in, but you could try
> axis.Date(1, xtime, xtime, "%Y %b", las=2, cex=0.7)
On Mon, 28 Apr 2008, eugen pircalabelu wrote:
> Hi List,
>
> I have the following time series and i want to be able to plot it while
> having the x-axis running from 1998 to 2006 but in a bi-annual format
>
> So here is my example:
>
> x<-sample (10:100, 17)
> x<-ts(x, start=c(1998,1), frequency=2)
> plot(x)
>
> When I plot the ts it goes from 1998 to 2006 by 2years, when in fact i
> want it to go from 1998 to 2006 with the following form:1998 may, 1998
> nov, 1999 may, 1999 nov, 2000 may, 2000 nov...... 2005 may, 2005 nov,
> 2006 may. I have searched nabble for something similar, saw ?plot() but
> this problem is still a mystery to me .
>
> Thank you and have a great day ahead!
> R-help at r-project.org mailing list
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> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
--
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
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