On Tue, 2008-06-10 at 16:56 -0600, Ranney, Steven wrote: > I'm tyring to fit a relatively simple nls model to some data, but keep coming > up against the same error (code follows): > > Oto=nls(Otolith ~ Linf*(1-exp(-k(AGE-to))), > data = ages, > start = list(Linf=1000, k=0.1, to=0.1), > trace = TRUE)
Try putting a * in after the k in the formula. Simon. > > The error message I keep getting is "Error in eval(expr, envir, enclos) : > could not find function "k"". I've used this line of code for other nls > models (with different data, parameter estimates, etc.), but have never > gotten this error. The data is > > AGE,Otolith,Scale > 1,207.1052632,207.1052632 > 2,329.962963,332.7586207 > 3,401.9473684,406 > 4,422,413.1111111 > 5,452.6785714,458.34375 > 6,510.75,533 > 7,477,674 > 8,643,704 > 9,,615 > 10,695.5, > 12,615, > > Are the missing values (e.g., no value for Otolith, AGE 9) having an effect? > I am using Tinn-R as an editor > > I'm new to R, trying to get away from Rcmdr (though it has been helpful), and > still trying to learn the language with the aid of several books on the R. A > search of the R Archive did not prove fruitful. > > Thanks in advance, > > SR > > Steven H. Ranney > Graduate Research Assistant (Ph.D) > USGS Montana Cooperative Fishery Research Unit > Montana State University > PO Box 173460 > Bozeman, MT 59717-3460 > > phone: (406) 994-6643 > fax: (406) 994-7479 > > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. -- Simon Blomberg, BSc (Hons), PhD, MAppStat. Lecturer and Consultant Statistician Faculty of Biological and Chemical Sciences The University of Queensland St. Lucia Queensland 4072 Australia Room 320 Goddard Building (8) T: +61 7 3365 2506 http://www.uq.edu.au/~uqsblomb email: S.Blomberg1_at_uq.edu.au Policies: 1. I will NOT analyse your data for you. 2. Your deadline is your problem. The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data. - John Tukey. ______________________________________________ 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.
