On 13 February 2012 14:46, ilai <ke...@math.montana.edu> wrote: > The function you posted runs without error (on these 6 lines), but > does not return anything that looks remotely like a sum, or cumsum of > anything. Can you clarify what you are trying to do? I assume by "sum > of every other row" you don't mean summing Time, X and Y for rows > 1,3,5,..., ?
I'm trying to get a piecewise sum of every n rows in a given column in this data set. > For the sum of sens2[c(1,3,5,...),] for every column (assuming no NA's > in the data) you could I do format checking well before getting to this stage in the analysis. > > (1:nrow(sens2) %% 2) %*% as.matrix(sens2) That does not do what I want... Again, what it should return is a list of the sum of the current and preceding row. -- Sent from my mobile device Envoyait de mon portable ______________________________________________ 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.
