ClpAmplObjective.hpp

/* $Id$ */
// Copyright (C) 2007, International Business Machines
// Corporation and others.  All Rights Reserved.
// This code is licensed under the terms of the Eclipse Public License (EPL).

#ifndef ClpAmplObjective_H
#define ClpAmplObjective_H

#include "ClpObjective.hpp"
#include "CoinPackedMatrix.hpp"

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

/** Ampl Objective Class

*/

class ClpAmplObjective : public ClpObjective {

public:
  ///@name Stuff
  //@{

  /** Returns gradient.  If Ampl 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);
  /// Resize objective
  /** 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;
  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);
  /** Given a zeroed array sets nonlinear columns to 1.
        Returns number of nonlinear columns
     */
  virtual int markNonlinear(char *which);

  /// Say we have new primal solution - so may need to recompute
  virtual void newXValues();
  //@}

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

  /// Constructor from ampl info
  ClpAmplObjective(void *amplInfo);

  /** Copy constructor .
    */
  ClpAmplObjective(const ClpAmplObjective &rhs);

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

  /// Destructor
  virtual ~ClpAmplObjective();

  /// Clone
  virtual ClpObjective *clone() const;

  //@}
  ///@name Gets and sets
  //@{
  /// Linear objective
  double *linearObjective() const;
  //@}

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

private:
  ///@name Private member data
  /// Saved offset
  double offset_;
  /// Ampl info
  void *amplObjective_;
  /// Objective
  double *objective_;
  /// Gradient
  double *gradient_;
  //@}
};

#endif

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