only 0s may be mixed with negative subscripts
On 13 February 2012 14:46, ilai <keren at 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