Hi! I need to conditionally update a dataframe field based on values in other fields and can't find even how to search for this right. Sorry if this has been asked before.
But, specifically, I have a 490 X 221 dataframe and need to count, by row, how many fields in Dataframe$field_a...Dataframe$field_zz are non-null and enter this value in Dataset$ABCtaskNum. I have field name definitions in a vector "vars" and tried writing a custom function to handle the within-row calculation myfunct <-function () {for (i in 1:length(vars)) {if (vars[i] != NA) {Dataset$ABCtaskNum<-Dataset$ABCtaskNum+1}}} and then use "apply" to handle the row to row calculation Dataset <- apply(Dataset, 1, myfunc) Where Dataset already has field Dataset$ABCtaskNum set to 0 in all rows. But that didn't work. Doesn't help if I declare variables (vars and ABCtaskNum) in the function declaration either, but then I haven't quite figured out how best to do variable substitutions in R. Thanks for any help. Cheers Jon Soli Deo Gloria Jon Erik Ween, MD, MS Scientist, Kunin-Lunenfeld Applied Research Unit Director, Stroke Clinic, Brain Health Clinic Baycrest Centre for Geriatric Care Assistant Professor, Dept. of Medicine, Div. of Neurology University of Toronto Faculty of Medicine Posluns Building, 6th Floor, Room 644 Baycrest Centre for Geriatric Care 3560 Bathurst Street Toronto, Ontario M6A 2E1 Canada Phone: 416-785-2500 x3636 Fax: 416-785-2484 Email: [EMAIL PROTECTED] Confidential: This communication and any attachment(s) may contain confidential or privileged information and is intended solely for the address(es) or the entity representing the recipient(s). If you have received this information in error, you are hereby advised to destroy the document and any attachment(s), make no copies of same and inform the sender immediately of the error. Any unauthorized use or disclosure of this information is strictly prohibited. [[alternative HTML version deleted]] ______________________________________________ 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.