> summary(nlme(Btronc~a+b*dbh**2*haut, data=cbind(dat,g="a"), fixed=a+b_1, > start=start, > > groups=~g, weights=varPower(form=~dbh)))
Shouldn't 'fixed' be a formula? Perhaps a+b~1? Bill Dunlap TIBCO Software wdunlap tibco.com On Mon, Oct 24, 2016 at 9:03 AM, Santiago Bueno <swbu...@gmail.com> wrote: > Dear people: > > > I am getting the following error when trying to run the piece of code > below. Any insights?? > > > > Error in nlme.formula(Btronc ~ a + b * dbh^2 * haut, data = cbind(dat, : > > object 'a' not found > > > > library(nlme) > > start <- coef(lm(Btronc~I(dbh**2*haut),data=dat)) > > names(start) <- c("a","b") > > summary(nlme(Btronc~a+b*dbh**2*haut, data=cbind(dat,g="a"), fixed=a+b_1, > start=start, > > groups=~g, weights=varPower(form=~dbh))) > > > Best, > > > Santiago > > [[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. > [[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.