On Tue, May 26, 2015 at 5:14 AM, wong jane <jane.wong...@gmail.com> wrote:
> There are functions which use variable names as parameters in some R > packages. However, if the variable name is stored in another variable, how > can I pass this variable to the function. Taking the "rms" package as an > example: > > > library(rms) > n <- 1000 > age <- rnorm(n, 50, 10) > sex <- factor(sample(c('female','male'), n,TRUE)) > > y <- rnorm(n, 200, 25) > ddist <- datadist(age, sex) > options(datadist='ddist') > fit <- lrm(y ~ age) > Predict(fit, age, np=4) > options(datadist=NULL) > > Here "age" was a variable name passed to Predict() function, but if "age" > was stored in variable "var", that is, var <- "age", how can I pass "var" > to Predict() function? The purpose is that I want to change the parameter > of Predict() in a loop. > > Please turn off HMTL email. The forum software doesn't really like it. What you want is the "get()" function. var<-"age" library(rms) n <- 1000 age <- rnorm(n, 50, 10) sex <- factor(sample(c('female','male'), n,TRUE)) y <- rnorm(n, 200, 25) # ddist <- datadist(age, sex) ddist <- datadist(get(var),sex) options(datadist='ddist') fit <- lrm(y ~ age) # Predict(fit, age, np=4) Predict(fit,get(var),np=4) options(datadist=NULL) -- My sister opened a computer store in Hawaii. She sells C shells down by the seashore. If someone tell you that nothing is impossible: Ask him to dribble a football. He's about as useful as a wax frying pan. 10 to the 12th power microphones = 1 Megaphone Maranatha! <>< John McKown [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.