Re: [R] inverse function of SSlogis

hello gabor, thanks a lot for that. i'll try. best wishes, kay -- View this message in context: http://n4.nabble.com/inverse-function-of-SSlogis-tp1694995p1695061.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org

Re: [R] inverse function of SSlogis

Try this. More info at http://ryacas.googlecode.com : > library(Ryacas) > Asym <- Sym("Asym"); xmid <- Sym("xmid"); scal <- Sym("scal") > x <- Sym("x"); y <- Sym("y") > Solve(Asym/(1+exp((xmid-x)/scal))==y, x) expression(list(x == xmid - log(Asym/y - 1) * scal)) On Mon, Mar 29, 2010 at 7:24 AM