deoptimization

问题 I've written a simulation program in C++ and like to find parameters in R, using DEoptim. Sometimes everything works well and sometimes DEoptim stops and tells: Error in DEoptim(simulate, lower = lb, upper = ub, control = opt) : NaN value of objective function! Perhaps adjust the bounds. My R-script defines a function that calls the external binary. The parameters are attached to the command. I tested my C++ program and have never seen NaN's returned. Further, to investigate I check for NaN's