> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of > [EMAIL PROTECTED] > Sent: Thursday, August 21, 2008 12:15 PM > To: r-help@r-project.org > Subject: [R] mean for vector with NA > > I am trying to find the mean for the elements in the vector > > Incubation=as.POSIXlt(OnsetTime)-as.POSIXlt(MealTime) > > where > > OnsetTime=c(NA,"1940-04-19 00:30","1940-04-19 00:30","1940-04-19 > 00:30",NA,"1940-04-18 22:30","1940-04-18 22:30","1940-04-19 > 02:00","1940-04-19 01:00","1940-04-18 23:00",NA,NA,NA,"1940-04-19 > 02:00",NA,"1940-04-19 10:30","1940-04-19 00:30","1940-04-18 > 22:15",NA,"1940-04-18 22:00","1940-04-19 01:00","1940-04-18 > 23:00",NA,"1940-04-18 21:45",NA,"1940-04-18 21:45","1940-04-19 > 01:00",NA,"1940-04-18 23:00",NA,"1940-04-18 21:00","1940-04-19 > 01:00","1940-04-19 01:00",NA,NA,"1940-04-18 21:15",NA,"1940-04-18 > 23:30","1940-04-19 01:00","1940-04-18 21:30",NA,"1940-04-19 > 02:30","1940-04-19 02:00","1940-04-18 21:30",NA,NA,"1940-04-19 > 00:30","1940-04-19 01:00","1940-04-18 22:30",NA,NA,"1940-04-18 > 15:00",NA,"1940-04-19 00:00","1940-04-18 23:00",NA,"1940-04-18 > 22:30","1940-04-19 01:00","1940-04-19 02:30","1940-04-18 > 23:30",NA,NA,NA,NA,"1940-04-19 01:00","1940-04-19 > 00:30",NA,NA,NA,"1940-04-19 00:30","1940-04-19 01:00","1940-04-19 > 00:00",NA,"1940-04-19 02:15","1940-04-18 23:00") > MealTime=c(NA,"1940-04-18 20:00","1940-04-18 18:30","1940-04-18 > 18:30",NA,"1940-04-18 19:30","1940-04-18 19:30","1940-04-18 > 19:30","1940-04-18 22:00","1940-04-18 19:00",NA,NA,NA,"1940-04-18 > 19:30",NA,NA,NA,NA,NA,NA,"1940-04-18 > 22:00",NA,NA,NA,NA,NA,"1940-04-18 > 22:00",NA,NA,"1940-04-18 22:00",NA,"1940-04-18 22:00","1940-04-18 > 22:00",NA,NA,NA,NA,NA,"1940-04-18 22:00",NA,NA,NA,NA,NA,"1940-04-18 > 22:00",NA,NA,"1940-04-18 19:00",NA,NA,NA,"1940-04-18 > 11:00",NA,NA,NA,NA,NA,"1940-04-18 22:00","1940-04-18 > 19:30","1940-04-18 19:30",NA,NA,NA,NA,"1940-04-18 > 22:00",NA,"1940-04-18 19:30","1940-04-18 19:30",NA,NA,"1940-04-18 > 19:30","1940-04-18 19:30","1940-04-18 22:00",NA,NA) > > I have tried > > mean(Incubation) > > and > > mean(as.numeric(Incubation)) > > but I think that, since there are so many NA values in Incubation, R > gives a mean value of NA. Is there any way of either extracting all > numeric values (i.e. all non-NA values) from the Incubation > vector, or > finding the mean value of only the numeric values in the Incubation > vector? > > Brian >
Try mean(Incubation, na.rm=TRUE) Hope this is helpful, Dan Daniel J. Nordlund Washington State Department of Social and Health Services Planning, Performance, and Accountability Research and Data Analysis Division Olympia, WA 98504-5204 ______________________________________________ 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.