Minotaur::Objective Class Reference

#include <Objective.h>

Public Member Functions
	Objective ()
	Default constructor.
	Objective (double cb=0.0, ObjectiveType otyp=Minimize)
	Objective (FunctionPtr fPtr, double cb=0.0, ObjectiveType otyp=Minimize)
	Objective (FunctionPtr fPtr, double cb, ObjectiveType otyp, std::string name)
virtual	~Objective ()
	Destroy.
double	getConstant () const
	Return the constant term in this objective.
ObjectiveType	getObjectiveType () const
	Return the type (Maximize or Minimize) of this objective.
FunctionType	getFunctionType () const
	Return the type of the function in objective.
ObjState	getState () const
	Return the state of the objective. Fixed, removed, freed etc.
virtual const std::string	getName () const
FunctionPtr	getFunction () const
	Return the function in the objective.
LinearFunctionPtr	getLinearFunction () const
QuadraticFunctionPtr	getQuadraticFunction () const
NonlinearFunctionPtr	getNonlinearFunction () const
void	write (std::ostream &out) const
	Print the objective function to the output stream.
double	eval (const double *x, int *err) const
void	evalGradient (const double *x, double *grad_f, int *error)
void	evalGradient (VariableGroup &point, double *grad_f)

Friends
class	Problem

Detailed Description

The Objective class is meant to implement an objective function for the problem (or formulation). There are only a few differences between Objective and Constraint. The Objective has a sense (Maximize or Minimize) associated with it. The objective may also have a constant term. Like a constraint, an objective has a function and lower and upper bounds. These bounds are optional. An objective must have the ability to be evaluated at a given point, and also to return its gradient at a given point.

Minotaur will always minimize an objective internally. So if the objective is to maximize, it will try to minimize the negative.

Constructor & Destructor Documentation

Objective() [1/2]

Objective::Objective	(	double	cb = 0.0,
		ObjectiveType	otyp = Minimize
	)

Create an objective with a specific id, constant term and sense. Does not need a function. A default name is created.

Objective() [2/2]

Objective::Objective	(	FunctionPtr	fPtr,
		double	cb,
		ObjectiveType	otyp,
		std::string	name
	)

Create an objective with a specific function, id, constant term, sense and a name.

Member Function Documentation

eval()

double Objective::eval	(	const double *	x,
		int *	err
	)		const

Evaluate the objective function (along with the constant term) at the given point x.

evalGradient() [1/2]

void Objective::evalGradient	(	const double *	x,
		double *	grad_f,
		int *	error
	)

Evaluate the gradient at the given point x and fill in the gradient values in the array grad_f. The array grad_f is assumed to have the required size (equal to number of variables in the problem).

evalGradient() [2/2]

void Minotaur::Objective::evalGradient	(	VariableGroup &	point,
		double *	grad_f
	)

Evaluate the gradient at the given point and fill in the gradient values in the array grad_f. The array grad_f is assumed to have the required size (equal to number of variables in the problem).

Todo:

XXX: replace this function by the one below.

getLinearFunction()

LinearFunctionPtr Objective::getLinearFunction

(

)

const

Return the linear function part of the objective function. Could be NULL.

getNonlinearFunction()

NonlinearFunctionPtr Objective::getNonlinearFunction

(

)

const

Return the nonlinear function part of the objective function. Could be NULL.

getQuadraticFunction()

QuadraticFunctionPtr Objective::getQuadraticFunction

(

)

const

Return the quadratic function part of the objective function. Could be NULL.

Friends And Related Symbol Documentation

Problem

friend class Problem

friend

Only Problem class can modify an Objective. All modification methods are private.

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The documentation for this class was generated from the following files:

• /home/amahajan/tmp/minotaur-test/src/base/Objective.h
• /home/amahajan/tmp/minotaur-test/src/base/Objective.cpp