Thanks a lot, Sarah.
I assume, if the values against which I am comparing are REALLY zero
("0") - then even the first one (mean(testvec[testvec != 0])) should
work, right?
DimitriOn Tue, Jul 19, 2011 at 4:56 PM, Sarah Goslee <sarah.gos...@gmail.com> wrote: > In the more general case, that approach is prone to machine precision > error (FAQ 7.31). > > Here's a clunky but safer alternative: > >> set.seed(1234) >> testvec <- sample(0:10, 100, replace=TRUE) >> mean(testvec) > [1] 4.31 >> mean(testvec[testvec != 0]) > [1] 4.842697 >> mean(testvec[!sapply(testvec, function(x)isTRUE(all.equal(x, 0)))]) > [1] 4.842697 >> > > (Is there an elementwise equivalent to all.equal() that I'm missing?) > > Sarah > On Tue, Jul 19, 2011 at 4:48 PM, Weidong Gu <anopheles...@gmail.com> wrote: >> You can do it by subsetting or indexing >> >> r<-c(0,0,0,rnorm(10,10,5)) >>> mean(r) >> [1] 8.052215 >>> mean(r[r!=0]) >> [1] 10.46788 >> >> Weidong Gu >> >> On Tue, Jul 19, 2011 at 4:36 PM, Dimitri Liakhovitski >> <dimitri.liakhovit...@gmail.com> wrote: >>> Sorry if it's been discussed before - don't seem to find it. >>> I'd like to calculate a mean while ignoring zeros. >>> "mean" doesn't seem to have an option for that. >>> Any other function/package that could do it? >>> >>> Thanks for a pointer! >>> >>> -- >>> Dimitri Liakhovitski >>> marketfusionanalytics.com >>> > > > > -- > Sarah Goslee > http://www.functionaldiversity.org > -- Dimitri Liakhovitski marketfusionanalytics.com ______________________________________________ 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.
