Even though I work with R since a year or so I still struggle with simple problems. I hope someone can help me with this. Been trying for days and am a little frustrated now.
I have a data frame somewhat like the one bellow: dattrial<-data.frame(a=c(1,NA,rnorm(4,10)), Week=c(3,3,3,4,4,4)) I want to know how many NAs I have in week 3 and in week 4. -- View this message in context: http://r.789695.n4.nabble.com/count-NAs-per-week-tp4643351.html Sent from the R help mailing list archive at Nabble.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.