[Gretl-users] Re: Question about root-finding of a non-linear equation

To the best of my knowledge, we do not have in gretl a direct root-finder for a non-linear equation (apart from "polroots" for polynomials) , say f(x,a) - b = 0 with function f continuous / non-linear, a,b given and with task to find x. Assume that there indeed exists a unique solution x*. I thought I'd trick the system by specifying h(x,a,b) = [f(x,a) - b]^2 and ask the BFGScmin function to minimize h(x,a,b) (with numerical derivatives). Mathematically this looks sound, but is there something that lurks in the software/computational basement?