fpid_optimfun

FPID_OPTIMFUN Optimal FPID Design helper function
        Usage: z = fpid_optimfun(x,G,opt)
        where              
               x(1) = Kp   or  x(1) = lam (gains fixed)
               x(2) = Ki       x(2) = mu  
               x(3) = Kd
               ---------- (exponents fixed)
               x(4) = lam
               x(5) = mu
               
               G - FOTF object, plant transfer function
               opt.optim - optimization metric: 'ise', 'iae', 'itse' or
                           'itae'.
               opt.t, opt.dt - time vector, time step
               opt.wb, opt.wh, opt.N, opt.type - Oustaloup filter params,
                                                 type: 'oust' or 'ref'.
               opt.fix - 'e' to fix exponents, 'g' to fix gains, 'n' to
                         fix nothing; supply fixed parameters as:
                         opt.kp, opt.ki, opt.kd, opt.lam, opt.mu
               opt.nonfotf - (true/false): is a LTI model of type TF, ZPK,
                             SS is used instead of a FOTF object?
               opt.nfmodel - corresponding LTI model
                opt.sp - set point
                opt.cancelzero - (true/false) whether to cancel zeros
                                 to obtain a proper model
               opt.usesim - string; if unempty, simulate specified model
               in Simulink, use 'fpid_optimize_model.mdl' for the
               default model. If empty, Simulink is not invoked.