STK_OPTIM_FMINCON constructs an object of class 'stk_optim_fmincon'. CALL: ALGO = stk_optim_fmincon () constructs an algorithm object ALGO of class 'stk_optim_fmincon' with a default set of options. CALL: ALGO = stk_optim_fmincon (opt) constructs an algorithm object ALGO of class 'stk_optim_fmincon' with a user-defined set of options, defined by the structure opt.