Hi, I am trying to fit a curve to data. My command line is:
model10=nls(offspring~((A*c^k)/gamma(k))*((degdays-alpha)^(k-1))*exp(-c*(degdays-alpha)), start=list(A=30,k=2,c=.018,alpha=131)) I get the error message: Error in numericDeriv(form[[3]], names(ind), env) : Missing value or an infinity produced when evaluating the model In addition: Warning message: full precision was not achieved in 'gammafn' My starting values yield a curve very similar t to other models which I fitted successfully. So any suggestions? I've tried different starting values. -- View this message in context: http://www.nabble.com/using-nls-to-fit-a-curve-to-data-tp19332210p19332210.html Sent from the R help mailing list archive at Nabble.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.