Pat Schmitz wrote: > Both vector query's can select the values from the data.frame as written, > however in the first form assigning a value to said selected numbers fails. > Can you explain the reason this fails? > > dat <- data.frame(index = 1:10, Value = c(1:4, NA, 6, NA, 8:10)) > > dat$Value[dat$Value == "NA"] <- 1 #Why does this fails to work, > dat$Value[dat$Value %in% NA] <- 1 #While this does work? > > > #Particularly when str() results in an equivalent class > dat <- data.frame(index = 1:10, Value = c(1:4, NA, 6, NA, 8:10)) > str(dat$Value[dat$Value %in% NA]) > str(dat$Value[dat$Value == "NA"])
1. NA and "NA" are very different things 2. checkout is.na() and its help page -- Peter Dalgaard Center for Statistics, Copenhagen Business School Phone: (+45)38153501 Email: pd....@cbs.dk Priv: pda...@gmail.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.
