Gabor Grothendieck wrote: > Try port algorithm. Please provide complete reproducible code and data > when posting. > > >> y <- 1/(x <- 1:5) >> nls(y~k/x^n, start=list(k=1, n=1), algorithm = "port") >> > Nonlinear regression model > model: y ~ k/x^n > data: parent.frame() > k n > 1 1 > residual sum-of-squares: 0 > > Algorithm "port", convergence message: both X-convergence and relative > convergence (5) > > > thanks, but unfortunaltly not work
here data and problem: tmp=data.frame(t=c(0,40,100,330,950,15200), h=c(0.362,0.278,0.218,0.169,0.139,0.024)) fm=formula(t~ tr+ (ts-tr)/ ((1+ (a*h)^n)^(1-(1/n)))) start=list(a=0.05, n=1.5, ts=0.5, tr=0.05) p=nls(fm, data=tmp,start=start, algorithm = "port") ------ Error in numericDeriv(form[[3]], names(ind), env, ifelse(internalPars < : Missing value or an infinity produced when evaluating the model hope, someone can help Jarek ______________________________________________ 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.