Hi all, I would like to find the x position of an two asymptotes.
Here is a sample of what I would like to do: x <- seq(1, 153,, 153) a <- 85 m <- 65 s =-1.5 fn <- function (x, a, m, s) { a * (exp((m - x)/s) * (1/s))/((1 + exp((m - x)/s)))^2 } plot.deriv1 <- fn(1:153, a, m, s) I can find the midpoint/minimum of this function easily. However, I can not find the start and end of the two asymptote position (along the x). mid.point <- optimize(f=fn.sslogis.deriv1, interval=c(1:153), a=a, m=m, s=s)$minimum Thanks for your assistance, Katrina ______________________________________________ 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.