On 6/14/07, Greg Snow <[EMAIL PROTECTED]> wrote: > > Try: > > > lm( formula( paste( Ytext, '~ Xvar' ) ), data=X)
That type of construction is perilously close to parse(paste(...)) and we know what Thomas said about that (see fortune("parse")). A safer way of constructing a formula from names stored in a character variable is substitute(foo ~ Xvar, list(foo = as.name(Ytext)) > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] On Behalf Of Pedro Mardones > > Sent: Thursday, June 14, 2007 1:14 PM > > To: R-help@stat.math.ethz.ch > > Subject: [R] question about formula for lm > > > > Dear all; > > > > Is there any way to make this to work?: > > > > .x<-rnorm(50,10,3) > > .y<-.x+rnorm(50,0,1) > > > > X<-data.frame(.x,.y) > > colnames(X)<-c("Xvar","Yvar") > > > > Ytext<-"Yvar" > > > > lm(Ytext~Xvar,data=X) # doesn't run > > > > lm(Yvar~Xvar,data=X) # does run > > > > The main idea is to use Ytext as input in a function, so you > > just type "Yvar" and the model should fit.... > > Also, I need to avoid the expression X$Yvar~X$Xvar > > > > Thanks for any idea > > > > PM > > > > ______________________________________________ > > R-help@stat.math.ethz.ch 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@stat.math.ethz.ch 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@stat.math.ethz.ch 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.