Instead of > bmisds(age,gender,bmi)
Try the vectorized version > mapply(bmisds, age, gender, bmi) See ?mapply -Christos > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Chung-hong Chan > Sent: Wednesday, October 03, 2007 12:31 AM > To: [EMAIL PROTECTED] > Subject: [R] How to modify function for list > > Dear R Gurus, > > I have a function which calculate the BMI standard deviation > score based on the age and gender specific L, M, S value. > I have written a function like this > > bmisds <- function (age, gender, bmi){ > if (age ==1 & gender ==1) > { > bmif <- c(-1.013,16.133,0.07656) > } > else if (age ==1 & gender ==0) > { > bmif <- c(-1.79,16.421,0.07149) > } > else if (age == 2 & gender == 1) > { > bmif <- c(-1.403,15.58,0.07342) > } > else if (age == 2 & gender == 0) > { > bmif <- c(-2.045,15.861,0.07116) > } > .... > > (((bmi/bmif[2])**bmif[1] -1)/(bmif[1]*bmif[3])) } > > This function work when I supply a single variable, e.g. > bmisds(1,0,16) > > When I try it with a list, e.g. > age <- c(12,13,14) > gender <- c(0,1,1) > bmi <- c(14,15,16) > bmisds(age,gender,bmi) > > This function give me wrong answer and error msg. > Warning messages: > 1: the condition has length > 1 and only the first element > will be used in: if (age == 1 & gender == 1) { > > > How can I midify this function to work with list/vector? > > regards, > C > > > -- > CH Chan > Research Assistant - KWH > http://www.macgrass.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. > > ______________________________________________ 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.
