On Fri, Aug 20, 2010 at 2:19 PM, steven mosher <mosherste...@gmail.com> wrote: > A quick question > > x <- as.yearmon(2000 + seq(0, 23)/12) > x > [1] "Jan 2000" "Feb 2000" "Mar 2000" "Apr 2000" "May 2000" "Jun 2000" "Jul > 2000" "Aug 2000" "Sep 2000" "Oct 2000" "Nov 2000" "Dec 2000" "Jan 2001" > [14] "Feb 2001" "Mar 2001" "Apr 2001" "May 2001" "Jun 2001" "Jul 2001" "Aug > 2001" "Sep 2001" "Oct 2001" "Nov 2001" "Dec 2001" > data<-seq(1,24,by=1) > testzoo<-zoo(data,order.by=x) > > The operation I ant to perform on the zoo series is this. I will illustrate > with a small example and formula: > > the coredata of the zoo series is 1,2,3,4,5,6,7,8 ) > I want to calculate Result<- zoo[x]-zoo[x-1] (NA,1,1,1,1,1...NA) > The first element of course is undefined(NA). is there any method to do this > elegantly, padding NAs at the > start works but its ugly. if I get a simple function I can apply it to a > matrix of zoo series
zoo has a diff.zoo method: diff(testzoo) diff(testzoo, na.pad = TRUE) ______________________________________________ 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.
