Root search on results of minimization with free parameter

*To*: mathgroup at smc.vnet.net*Subject*: [mg114770] Root search on results of minimization with free parameter*From*: Philipp WeiÃgraeber <weissgraeber at fsm.tu-darmstadt.de>*Date*: Thu, 16 Dec 2010 05:50:36 -0500 (EST)

Hello all! I have a function f which is for example the result of a minimization with respect to x. It still depends on a parameter c. Now I want to find the root (or minima or whatever) of the the function f with respect to c. This seems does not work. I always get the errors "NMinimize::nnum: Function value is not a number" resp. "FindRoot::nlnum: The function value is not a list of numbers" Example: example[c_, x_] = x^2 + c/2; f[c_] := NMinimize[example[c, x], x][[1]]; FindRoot[f[c] == 0, {c, 14}] How can I implement this? My original problem is of course of more complex nature, but it boils down to this. Thank you Philipp