Hi Try
function rollapply from zoo.It can compute rolling results of functions. Make your y a zoo object and use rollapply(object, 3, var) Regards Petr r-help-boun...@r-project.org napsal dne 30.09.2009 12:37:36: > Dear R-user > > Suppose I have the following data > > y=c(2,1,5,8,11,3,1,7,50,21,33,7,60) > > x=data.frame(y) > > for(i in 4:nrow(x)) x[i,] =var(x[i-3:i-1,]) > > I'm trying to get a new variable with the variance of the 3 previous values > (just an example) and with NA in the three first positions. I know that my > for() is wrong > but I'm not able to find my error. > > Any idea? > > Thanks, > > Marlene. > > [[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. ______________________________________________ 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.
