Yes. I need to do implicit differentiation. After rearrangement, I got (x2 – x1) * b = log(1 / y - 1)
Take derivative of both sides with respect to y, I have (x2 – x1) * b’[y] = - 1/y(1-y) Since both (x2 – x1) and b’[y] are vectors, I cannot move (x2 – x1) to RHS. This is why I posted my question here to see if there is some R functions or some idea that can help me solve this problem. Thanks. Lisa -- View this message in context: http://r.789695.n4.nabble.com/Derivative-of-a-function-tp3631814p3633947.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.
