Like I said in my followup, please pass the maxgap argument: i.e., na.approx(x, maxgap = 4)
x <- zoo(1:20, Sys.Date() + 1:20) x[2:4] <- NA # Short run of NA's x[10:16] <- NA # Long run of NA's na.approx(x) # All filled in na.approx(x, maxgap = 4) # Only the short one filled in Michael On Tue, Apr 3, 2012 at 10:13 AM, jeff6868 <geoffrey_kl...@etu.u-bourgogne.fr> wrote: > Michael, > > First of all, thank you very much for your answer. > I've read your 2 answers, but I'm not really sure that they corresponds to > my problem of NAs. > I'll try to detail you a bit more. > > This problem concerns the second part of my program. In the first part, I've > already created a timeseries object with the library (timeseries). I had to > delete first all the wrong values in my data and replace it with NAs. > So my data contains already missing data (NAs), as I have cleaned it before. > > The thing is that sometimes I have small gaps of missing data (only 2 or 3 > following) like in "example 1" below: > > example 1: > > 09/01/2008 12:00 1.93 > 09/01/2008 12:15 3.93 > 09/01/2008 12:30 NA So here you have a small gap with only > 2 NAs > 09/01/2008 12:45 NA > 09/01/2008 13:00 4.93 > 09/01/2008 13:15 5.93 > > But sometimes, always in the same file, I have big gaps, such as 10 or more > NAs following each other like in "example 2" below: > > example 2: > > 09/01/2008 16:15 2.93 > 09/01/2008 16:30 2.93 > 09/01/2008 16:45 NA > 09/01/2008 17:00 NA > 09/01/2008 17:15 NA > 09/01/2008 17:30 NA > 09/01/2008 17:45 NA > 09/01/2008 18:00 NA So here you have a big gap with > more than 10 > NAs following each other > 09/01/2008 18:15 NA > 09/01/2008 18:30 NA > 09/01/2008 18:45 NA > 09/01/2008 19:00 NA > 09/01/2008 19:15 NA > 09/01/2008 19:30 NA > 09/01/2008 19:45 NA > 09/01/2008 20:00 NA > 09/01/2008 20:15 7.93 > 09/01/2008 20:30 7.93 > > So in the whole same file, I can have sometimes big gaps (2 or 3 NAs), > sometimes big or very big gaps (10 or 100 NAs following). > > The aim of my problem is to apply the function: na.approx(x) of the library > (zoo) to fill NAs ONLY for small gaps. > > If I just do: apply(na.approx(x)), it will fill all the NAs of my data (big > gaps + small gaps). It's exactly what I DON'T WANT. > > My problem is to say to R: " you apply the function (na.approx) to fill NAs > ONLY if you see 4 NAs maximum following each other (small gaps) (like > example 1)". "If you see more than 4 NAs following each other (big gaps like > in example 2), you keep these NAs and you DON'T fill this big gap". > > My question is: how can I say this to R? I don't know how to do it. > Hope I've been understandable this time ^^ > Thanks a lot again for all your answers! > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/filling-small-gaps-of-N-A-tp4528184p4528907.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.
