Hi Uli, I am not sure if this is the problem that you really want to solve. The answer is the solution to the equation y = x * T^(x-1), provided a solution exists. There is no optimization involved here. What is the real problem that you are trying to solve?
If you want to solve a more meaningful constrained optimization problem, you may want to try the "abalama" package which I just put on CRAN. It can optimize smooth nonlinear functions subject to linear and nonlinear equality and inequality constraints. http://cran.r-project.org/web/packages/alabama/index.html Let me know if you run into any problems using it. Best, Ravi. -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Uli Kleinwechter Sent: Monday, July 26, 2010 10:16 AM To: r-help@r-project.org Subject: [R] Optimization problem with nonlinear constraint Dear all, I'm looking for a way to solve a simple optimization problem with a nonlinear constraint. An example would be max x s.t. y = x * T ^(x-1) where y and T are known values. optim() and constrOptim() do only allow for box or linear constraints, so I did not succedd here. I also found hints to donlp2 but this does not seem to be available anymore. Any hints are welcome, Uli -- Uli Kleinwechter Agricultural and Food Policy Group (420a) University of Hohenheim D-70593 Stuttgart E-mail: u.kleinwech...@uni-hohenheim.de ______________________________________________ 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. ______________________________________________ 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.