Hello everybody, is there any way to treat NA's as zero when they are summed up with numbers, but to treat them as NA's when summed up only with NA's. Specifically want that: 5+NA=5, but NA+NA=NA (and not zero). Any ideas? Best, S.B. [[alternative HTML version deleted]]
On Oct 12, 2011, at 12:45 PM, Samir Benzerfa wrote:> Hello everybody, > > > > is there any way to treat NA's as zero when they are summed up with > numbers, > but to treat them as NA's when summed up only with NA's. > Specifically want > that: 5+NA=5, but NA+NA=NA (and not zero). >sum(x , na.rm=TRUE) -- David Winsemius, MD West Hartford, CT