search for: dattrial

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.

Hello, I'm quite new to R and still spend hours trying to figure out single things so I hope nobody rolls his eyes over my question. I have a data set over time and converted it to the POSTIXct format. I added a column in the data set for the week and the month. I try to get a plot which shows the weeks on the x-axis and the number of datasets without NAs on the y-axis. That doesn't