### 9.1 Objective Functions ¶

: Objective `(void)` ¶
: Objective `(const objective_fcn)` ¶
: Objective `(const objective_fcn, const gradient_fcn)` ¶
: Objective `(const Objective &a)` ¶

: `Objective&` operator = `(const Objective &a)` ¶

: `objective_fcn` objective_function `(void) const;` ¶

: `Objective&` set_objective_function `(const objective_fcn)` ¶

: `gradient_fcn` gradient_function `(void) const;` ¶

: `Objective&` set_gradient_function `(const gradient_fcn)` ¶