I'm assuming that you want to add b if 3<a<5.25. If so, there are many ways. One of them is
sum (b[a>3 & a<5.25]) This is very simple R coding. I recommend you spend some time learning the basics. There are very good tutorials at the R website. Julian [EMAIL PROTECTED] wrote: > Hello, > > A stupid question: > > I have an array with two columns, the first "a" acting as my index in 0.25 > steps, the second one "b" the column of interest. How can i sum up "b" only > for a specified window in "a" (as the window command for time series) > > a=seq(0,10,0.25) > b=runif(41) > c=data.frame(a,b) > > Sum up c if 3<a<5.25 > > How to do that? thanks > > marc ______________________________________________ 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.
