/* $Id: ClpLinearObjective.hpp 1525 2010-02-26 17:27:59Z mjs $ */
// Copyright (C) 2003, International Business Machines
// Corporation and others.  All Rights Reserved.
#ifndef ClpLinearObjective_H
#define ClpLinearObjective_H

#include "ClpObjective.hpp"

//#############################################################################

/** Linear Objective Class

*/

class ClpLinearObjective : public ClpObjective {

public:

     ///@name Stuff
     //@{

     /** Returns gradient.  If Linear then solution may be NULL,
         also returns an offset (to be added to current one)
         If refresh is false then uses last solution
         Uses model for scaling
         includeLinear 0 - no, 1 as is, 2 as feasible
     */
     virtual double * gradient(const ClpSimplex * model,
                               const double * solution, double & offset, bool refresh,
                               int includeLinear = 2);
     /** Returns reduced gradient.Returns an offset (to be added to current one).
     */
     virtual double reducedGradient(ClpSimplex * model, double * region,
                                    bool useFeasibleCosts);
     /** Returns step length which gives minimum of objective for
         solution + theta * change vector up to maximum theta.

         arrays are numberColumns+numberRows
         Also sets current objective, predicted and at maximumTheta
     */
     virtual double stepLength(ClpSimplex * model,
                               const double * solution,
                               const double * change,
                               double maximumTheta,
                               double & currentObj,
                               double & predictedObj,
                               double & thetaObj);
     /// Return objective value (without any ClpModel offset) (model may be NULL)
     virtual double objectiveValue(const ClpSimplex * model, const double * solution) const ;
     /// Resize objective
     virtual void resize(int newNumberColumns) ;
     /// Delete columns in  objective
     virtual void deleteSome(int numberToDelete, const int * which) ;
     /// Scale objective
     virtual void reallyScale(const double * columnScale) ;

     //@}


     ///@name Constructors and destructors
     //@{
     /// Default Constructor
     ClpLinearObjective();

     /// Constructor from objective
     ClpLinearObjective(const double * objective, int numberColumns);

     /// Copy constructor
     ClpLinearObjective(const ClpLinearObjective &);
     /** Subset constructor.  Duplicates are allowed
         and order is as given.
     */
     ClpLinearObjective (const ClpLinearObjective &rhs, int numberColumns,
                         const int * whichColumns) ;

     /// Assignment operator
     ClpLinearObjective & operator=(const ClpLinearObjective& rhs);

     /// Destructor
     virtual ~ClpLinearObjective ();

     /// Clone
     virtual ClpObjective * clone() const;
     /** Subset clone.  Duplicates are allowed
         and order is as given.
     */
     virtual ClpObjective * subsetClone (int numberColumns,
                                         const int * whichColumns) const;

     //@}

     //---------------------------------------------------------------------------

private:
     ///@name Private member data
     /// Objective
     double * objective_;
     /// number of columns
     int numberColumns_;
     //@}
};

#endif
