When I run gnls I get the error:
Error in nls(y ~ cbind(1, 1/(1 + exp((xmid - x)/exp(lscal)))), data = xy, : step factor 0.000488281 reduced below 'minFactor' of 0.000976563 My first thought was to decrease minFactor but gnlsControl does not contain minFactor nor nlsMinFactor (see below). It does however contain nlsMaxIter and nlsTol which I assume are the analogs of maxiter and tol in nls.control. I would be happy to hear from anyone who has an idea on what parameters in gnlsControl to change to get convergence. Cheers Dan Coleman Genentech Inc. > gnlsControl function (maxIter = 50, nlsMaxIter = 7, msMaxIter = 50, minScale = 0.001, tolerance = 1e-06, nlsTol = 0.001, msTol = 1e-07, msScale = lmeScale, returnObject = FALSE, msVerbose = FALSE, apVar = TRUE, .relStep = (.Machine$double.eps)^(1/3), nlmStepMax = 100, opt = c("nlminb", "optim"), optimMethod = "BFGS", minAbsParApVar = 0.05) { list(maxIter = maxIter, nlsMaxIter = nlsMaxIter, msMaxIter = msMaxIter, minScale = minScale, tolerance = tolerance, nlsTol = nlsTol, msTol = msTol, msScale = msScale, returnObject = returnObject, msVerbose = msVerbose, apVar = apVar, nlmStepMax = nlmStepMax, opt = match.arg(opt), optimMethod = optimMethod, .relStep = .relStep, minAbsParApVar = minAbsParApVar) } > nls.control $maxiter [1] 50 $tol [1] 1e-05 $minFactor [1] 0.0009765625 [[alternative HTML version deleted]] ______________________________________________ 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.