Assuming that at the end all of them are dead, you can do the following: sum(deaths)-cumsum(deaths)
Regards, Moshe. --- On Wed, 2/9/09, Frostygoat <frostyg...@gmail.com> wrote: > From: Frostygoat <frostyg...@gmail.com> > Subject: [R] Basic population dynamics > To: r-help@r-project.org > Received: Wednesday, 2 September, 2009, 4:48 AM > > Hello, > > For insect mortality data I'm trying to get an R script > that will take > the data from the raw form and convert it to Lx (% > survival) for a > number of treatments. The raw data has the number of > days lived for > each individual for the respective treatment. Thus, > for example, when > R selects the data for a single treatment I end up with the > following > vectors: > > >day=seq(from=0,to=6) > >deaths=c(0,0,2,0,0,1,6) > > where deaths is the number of deaths on a given day. Now I > need to > create a new vector with the number alive for each day and > this is > where I'm stuck... I've tried to work various for and while > loops but > haven't had success. The vector should be: > > >Alive=c(9,9,7,7,7,6,0) > > I realize it is a very basic problem that is easily > accomplished in > one's head or on a spreadsheet but in the context of the > size of the > data set I wish to have R do it for me. I would welcome > any > suggestions please. > > Best regards. > > ______________________________________________ > 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.
